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MCQ's Biology F.Sc. Notes 2011-12 Inter Part I
1. Which of the following is the characteristic
of the living thing?
A. have specific shape
B. have regular shape
C. have organized body
D. none of the above
2. Which of the followings includes in homeostasis?
a. To maintain the shaped of the body
b. To maintain the balance of the body
c. To maintain the temperature of the body
d. To keep the animal away from the body
3. Your hearts starts beating before seven month
of your birth. The
study of your body at this stage comes within:
(a) Morphology (b) Embryology (c) Anatomy (d)
Histology
4. A doctor is studying the contraction and
relaxation of a heart. He
is studying:
(a) Morphology (b) Embryology (c) Anatomy (d)
Histology
5. Study of different parts of eye is called
(a) Histology (b) Anatomy (c) Physiology (d)
None of these
6. A biologist removes some bones of dinosaurs
from a rock. He is
studying:
(a) Morphology (b) Paleontology (c) Ecology (d)
None of these
7. Darwin sys, “man has formed from monkey”. He
talked about
(a) Fossil (b) Evolution (c) Taxonomy (d) None
of these
8. Kangaroo lives in Australia but buffaloes
lives in Pakistan. The
study of this distribution of animals is called
(a) Ecology (b) Environmental biology (c)
Taxonomy (d) Zoogeography
9. The study of structure of molecule of starch
is called:
(a) Molecular biology (b) Biochemistry (c)
Morphology (d) None
10. The study of Amoeba comes with in the branch
of biology:
(a) Taxonomy (b) Ecology (c) Microbiology (d)
None
11. The study of affects of pollution comes
within:
(a) Environmental biology (b) Taxonomy (c)
Physiology (d) Genetics
12. The study of organisms living in lake is
called:
(a) Marine biology (b) Taxonomy (c) Physiology
(d) Fresh water biology
13. The study of amount salt, temperature etc of
water of sea comes
within:
(a) Environmental biology (b) Taxonomy
(c) Marine biology (d) None of the above
14. The study of life cycle of plasmodium comes
within:
(a) Parasitology (b) Taxonomy
(c) Physiology (d) None of the above
15. The grouping of men is:
(a) Human biology (b) Social biology
(c) Biotechnology (d) None of above
16. The use of yeast in banking industry, and
use of bacteria for
making yogurt from milk are studied in:
(a) Human biology (b) Social biology
(c) Biotechnology (d) None of above
17. A biologist studies all structure and
functions of different parts
of a man. His work is included in branch of
biology called:
(a) Human biology (b) Social biology
(c) Biotechnology (d) None of above
18. Biological organization means:
a. Study of different organisms
b. Study of different branches of biology
c. Study of All the subjects of sciences
d. Study of biology at different levels
19. Trace elements are those:
a.Which are necessary for the organisms
Which are present in a very small quantity in
the body
Which are required in small quantity in the
body.
Which do not require to body.
20. Common bio elements are:
Calcium, phosphorus and carbon
Nitrogen, oxygen and hydrogen
Calcium, copper and carbon
(a) and (b)
21. Protoplasm is a:
(a) second name of cell (b) second name of
cytoplasm
(c) second name of Nucleolus(d) (b) and (c)
22. Bioelements are those elements:
Which are eaten by the organisms
Which are formed within the organisms
Which are used in the chemical compounds in the
organisms
Which are released by the organisms
23. Which statement is not correct about
biosphere:
(a) It is present on the earth (b) It is present
in the oceans
(c) It is present in the river (d) It is present
in the space.
24. Ecosystem is composed of:
(a) a community (b) a population
(c) a species (d) none of the above
25. Which of the followings is an organ system?
(a) oesophagus (b) Stomach
(c) intestine (d) All (a) and (c)
26. Which one of the followings is an organ?
(a) Cornea (b) Retina
(c) Eye (d) Eye muscles
27. Which of the followings is a tissue?
(a) Heart (b) stomach
(c) bone (d) Liver
28. Skin is:
(a) an organ (b) a tissue
(c) an organ system (d) None of all
29. ATP is a nucleotide. It is a:
(a) Micromolecules (b) Macromolecule
(c) Microelement (d) Microelement
30. Carbon dioxide is a compound of carbon. It
is:
(a) an inorganic compound (b) an organic
compound
(c) Both (a) and (b) (d) none of the above
31. Nucleus is:
(a) an organelles (b) Protoplasm
(c) cytoplasm (d) None of the above
32. A prokaryotic cell:
has well defined nucleus
is without nucleus and DNA
is without nucleus but DNA is present
None of above
33. A eukaryotic cell:
(a) Without well defined nucleus (b) is without
nucleus and DNA
(c) is with nucleus but DNA is absent(d) has
both nucleus and DNA
34. Number of persons living in Multan is called
(a) Population of Multan (b) Community of Multan
(c) Ecosystem of Multan (d) None of above
35. Community of Lahore includes:
All the humans living in Lahore
All the organisms living in Lahore
All the animals living in Lahore
All the plants in Lahore.
36. Gene frequency mean:
Number of genes present in an organism
Number of genes present in a population
Number of genes present in a community
None of above
37. An island in an sea is a:
(a) a population (b) Simple community
(c) complex community (d) None of the above
38. A dog kills a rabbit
(a) Rabbit is a predator (b) Dog is a prey
(c) Dog is a predator (d) Both are predator
39. Which one of the following is a biome:
(a) An ocean (b) A river
(c) Conifer forest (d) A garden
40. The fossils present in the older layer of a
rock could be:
Ancestor of the fossils present in the younger
sediments
Have equal age as that of younger sediments
Offspring of the younger sediment
None of the above
41. The older sediments in a rock have:
Smaller amount of radioactive substance than the
younger one
Larger amount of radioactive substance than the
younger one
Equal amount of radioactive substance with the
younger one
Do not have radioactive substance at all
42. We are now living in:
(a) Proterozoic era (b) Paleozoic era
(c) Mesozoic era (d) Coenozoic era
43. Phyletic lineage means:
(a) 2000 Million years ago (b) 3000 Million
years age
(c) 4000 Million years age (d) 5000 Million
years age
44. Phyletic lineage means:
All the organisms have same ancestor and they
show similarities.
All the organisms have different ancestor but
they show certain
Similarities
All the organisms have same ancestor but they do
not show
Similarities
None of the above
45. Total number of species on the earth is:
(a) 2.5 Millions (b) 2 Millions
(c) 3.5 Millions (d) 1.5 Millions
46. The most abundant group on the earth is:
(a) Mammals (b) Birds
(c) Insects (d) Reptiles
47. Which group of the followings has lowest
number of species?
(a) Vascular plants (b) Animals
(c) Insects (d) Algae, protozoa and Prokaryotes
48. Measurement of temperature is:
(a) Quantitative (b) Qualitative observation
(c) None of the above
49. Mammals have hairs on their bodies. Dog also
have hairs on its
body. So dog is also a mammal. It is:
(a) Deductive reasoning (b) Inductive reasoning
(c) None of the above
50. Inductive reason moves from:
(a) Known towards unknown (b) Unknown towards
known
(c) Known towards known (d) none of the above
Answers
check your ability by matching your choice to
these
1. (c) 2. (c) 3. (b) 4. (d) 5. (b) 6. (b)
7. (b) 8. (d) 9. (a) 10.(c) 11.(a) 12.(d)
13.(c) 14.(a) 15.(b) 16.(c) 17.(a) 18.(d)
19.(b) 20.(d) 21.(d) 22.(c) 23.(d) 24.(d)
25.(d) 26.(c) 27.(c) 28.(a) 29.(a) 30.(a)
31.(a) 32.(c) 33.(d) 34.(a) 35.(b) 36.(b)
37.(b) 38.(c) 39.(c) 40.(a) 41.(a) 42.(d)
43.(b) 44.(a) 45.(a) 46.(c) 47.(d) 48.(a)
49.(a) 50.(b)
1. Bat is a flying bird.
2. Hydra is diploblastic animal.
3. Archaepteryx is a fossil bird.
4. Prototheria are egg-laying mammals.
5. Human heart is four-chambered.
6. Fishes respire through skin.
7. Intracellular digestion occurs between the
cells.
8. Frog is a carnivorous animal.
9. Typhlosol is a dorsal absorptive ridge.
10. Water vascular system is present only in
Echinodermata.
11. Melatonin is secreted by cretins.
12. The heart of the crocodile consists of three
chambers.
13. The accumulation of nerves and sensory
organs in the head is known as Caphalization.
14. The Prototherians are pouched mammals.
15. Ammocoete is the larva of lamprey.
16. The spicules form the skeleton in sponges.
17. Plasmodium is an Endo-parasite.
18. Jelly-fish belongs to the class pieces.
19. Trypsin digests fats.
20. Pathology is the study of diseases.
21. Whale is a fish.
22. Planaria belongs to the phylum
Oplatyhelminthes.
23. Neuron is the unit of the nervous system.
24. Throid gland secretes thyrotopins bormone.
25. Ascaris is found as a parasite in the
intestine of man.
26. Amnion is the protective membrane of the
embryo of frog.
27. Trypanosome is an external parasite.
28. Arteries carry the blood away from the
heart.
29. Nephridia are respiratory organs.
30. Flagella are the organs of locomotion.
31. The inner ear is responsible for maintaing
the balance of the body.
32. The cross section of the spinal cord shows
the gray matter lying on the outside.
33. Pathology is the study of disease.
34. Gastrozooids are reproductive Zooids of the
colony.
35. Amphioxus belongs to sub-phylum vertebrate.
36. Retina contains rods and cones.
37. Larynx is a part of the Digestive system.
38. Molluscus secrete shells of various types.
39. Mammals are Warm-blooded animals.
40. Intracellular digestion takes place between the cells.
41. Kiwi is a flying bird.
Zoology XI Karachi Board MCQs
1. Sacculina belongs to __________.
(Arthropoda, Nematoda, Annelida)
2. The locomotory organs of sea star are
__________.
(Parapoda, Setae, Tube-feet)
3. Prehensile tail is present in __________.
(El fish, Sea horse, Wall lizard)
4. Ascaris is parasite in __________.
(Stomach, Intestine, Liver)
5. Pineal glands secrete __________.
(Thyroxin, Melatonin, Esterogen)
6. Bicuspid valve lies between __________.
(Righ Auricle and right Ventricle, Left Auricle
and Ventricle, Right Auricle and Left Ventricle)
7. Monocytes and __________ are agrantocytes.
(Neutrophils, Colgi body, Lymhocytes)
8. Glucose is converted during glycolysis into
__________.
(Urea, Uric acid, Pyruvic Acid)
9. Liver-fluke lives in __________.
(Liver, Gall bladder, Bile duct)
10. The class Ophiurodiea belongs to the phylum
__________.
(Echimedermate, Aschelminthes, Urochordate)
11. The skeleton of a dog-fish is made of
__________.
(Bones, Cartilages, Muscles)
12. The prehensile tail is present in __________.
(Eel fish, Sea horse, Bat)
13. Rods and cones are present in the eye of a
__________.
(Cockroach, Human, Leech)
14. Each villus is provided with lymph vessels
called __________.
(Venules, Lacteals, Veins)
15. The organs of excretion in cockroach are
called __________.
(Nephridia, Malpighian Tubules, Gills)
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16. Ductless glands are known as __________.
(Endocrine Glands, Digestive Glands, Milk
Glands)
17. Leishmania is a parasite of __________.
(Intestine, Blood, Bile duct)
18. Each villus is provided with lymph vessels
called __________.
(Arteris, lacteals, Venules)
19. Throxin hormone is secreted by __________.
(Thyroid glands, Pituitary Glands, Adrenal
glands)
20. The body of __________ is covered by
epidermal scales __________.
(Amphibians, Reptiles, Birds)
21. Water vascular system is present in
__________.
(Star Fish, Sponge, Leech)
22. The free swimming larva of liver fluke is
__________.
(Trochophore, Miracidium, Glochidium)
23. Tape worms are parasites living in
__________.
(Intestine, Muscles, Lungs)
24. The Coelenterates bear stinging cells called
__________.
(Sporocysts, Conocysts, Nematocysts)
Zoology XI Karachi Board Fill in the Blanks
1. Salivary amylase digests carbohydrates in
__________ medium.
2. The life-cycle of Plasmodium in mosquito
discovered by __________.
3. The larva of Balanoglossus (acron worm( is
called __________.
4. Legless amphibians are included in class
__________.
5. Flame cells are found in __________.
6. Nephridia are the excretory organs of
__________.
7. Butterfly exhibits __________ metamorphosis.
8. Euplectella belongs to __________.
9. Termites live in __________ colony.
10. Reptiles, birds and mammals are collectively
called __________.
11. In sponges the spongocoel is lined with
__________.
12. Cyclops is an example of the phylum
__________.
13. In 1880 A.D Lavern discovered a protozoan
parasite in the __________ of a malaria patient.
14. A protozoan parasite __________ causes human
dysentery.
15. The organs of excretion in insects are
__________.
16. There are five pairs of gills in __________
class of fish.
17. Saccutina a parasite of __________.
18. Thyroxine contains __________.
19. The larva of polychaete is called __________.
20. Elephantiasis is caused by __________.
21. The cnidoblasts are present in the phylum
__________.
22. Rock mountain spotted fever is transmitted
by cetain __________.
23. The end product of carbohydrate digestion is
__________.
24. The contractile vacuole performs the
function of __________.
25. Scyphistoma is the larval form of
__________.
26. The study of the functions of the organs is
known as __________.
27. Nearly 200 years ago the mammals evolved
from __________
28. __________ is the largest gland.
29. Mantle is the characteristic of the phylum
__________.
30. Class __________ has the largest number of
species of the whole animal kingdom.
31. Kangaroo belongs to the sub class
__________.
32. The locomotory organs of polychaets are
__________.
33. Non-nucleated R.B.C are found in blood of
__________.
34. The fore-brain consists of Telencephalon and
__________.
35. Bat is a flying __________.
36. Phylum __________ and __________ include
marine animals.
37. __________ is the unit of excretory organs.
38. Respiration is the process of __________.
39. __________ is an example of Polymorphism.
40. Book lungs are the respiratory organs of
__________.
41. In insects the excretion is performed by
__________.
42. Class Agnatha is also called __________.
43. Cortisone hormone is seceted by __________
gland.
44. Swim bladder is found in the class
__________.
45. The larva of Neries is called __________.
46. Spider belongs to the class __________.
47. The heart of a bird is divided into
__________ chambers.
48. Cercaria is the larva of __________.
49. The dendrons carry inpulse towards
__________.
50. The outer layer of the wall of the eyeball
is known as __________.
51. Flame cells are the organs of __________.
52. Balano glosus is included in the Phylum
__________.
53. The meaning of malaria is __________.
54. The study of the internal structure of an
organism is called __________.
55. Flame cells are excretory organs of phylum
__________.
56. Trypanosome is a blood parasite.
57. The dissimilar teeth in mammals are called
__________.
58. The respiratory organs of insects are
__________.
59. The skeletal parts of sponges are called
__________.
60. Nematocysts are found in the phylum
__________.
61. Enzyme pepsin is secreted by the __________
glands.
Botany True and False XI Karachi Board True and False intermediate board karachi
1. Bacteria are closely related to blue-green
algae.
2. Virus cells are prokaryotic.
3. Cocci are kidney-shaped.
4. The membrane surrounding vacuole is called
leucoplast.
5. Ulva is a blue green plant.
6. Female sex organs in Marchantia are borne on
Antheriodiophores.
7. The androecium in mustard is called
Tetradenamous.
8. Phylloclade is the modification of leaf.
9. Marchantia is a water plant.
10. Angiosperms are non-bearing plants.
11. Plumule develops into the root system.
12. Ribosomes are the centres of protein
synthesis.
13. Marchantia is a dioecious plant.
14. Phanerogams are flowering plants.
15. Endosperm is not the food storage tissue of
a seed.
16. In protoplasm water is about 80%.
17. Animal and plant cells do not differ from
each other.
18. Bacillus are rod-like or kidney-shaped.
19. Bryophytes have well-developed conducting
tissues.
20. Ulva is a sea weed.
21. Gemma cup cannot develop into a Marchantia
plant.
22. Zoospores in Stigeoclonium is
quadriflagellated.
23. Euglena has the characteristics of plant
only.
24. Phycocyanin pigment is found in
Chlamydomonas.
25. The plant body of Ulva is made up of
mycelium.
26. Eukaryotes include those organisms that lack
membrane around nucleus, mitochondria and colgi apparatus.
27. For the first time, cell was discovered by
Robert Hooks.
28. Plasma membrane is composed of cellulose.
29. In family Fabaceae the fruit is legume.
30. Spermatophytes include ferns and mosses.
31. Capitulum is a collection of flowers.
32. Raphanus sativus belongs to the family
Poaceae.
33. When petals are free, the condition is
called polypetalous.
34. Virus is a connecting link between living
and non-living.
35. Pinus is a plant which bears seeds but no
fruits.
36. All the cells arise from pre-existing cell.
37. Ulva is a fresh water algae.
38. Stegioclonium is not heterotrichous.
39. Berry is an example of a simple fleshy
fruit.
40. The seeds of pea plant are endospermic.
41. Rhizopus is a saprophytic fungus.
42. The endosperm in angiosperms is diploid.
43. The cryptogams are flowering plants.
44. Legume is an example of simple fruit.
45. In vallisnaria pollination takes place
through water.
Botany
MCQS XI Karachi Board MCQs
1. The male gamete of Selaginella is __________.
(Biflagellate, Multiflagellate, Nonflagellate,
Monoflagellate)
2. Stomata are organs which help in __________.
(Transpiration, Locomotion, Digeation, Growth(
3. Chlamydomonas is __________.
(Algae, Fungi, Multicellular, Non-motile)
4. Potato belongs to the family __________.
(Cruciferae, Fabaceae, Poaceae, Solanaceae)
5. Ginger is a __________.
(Fruit, Root, Rhizoma, Corn)
6. Hypogeal germination takes place by
elongation of __________.
(Celeorhiza, Epicotyle, Radicle, Hypocotyle)
7. Phyllode is the modification of __________.
(Alerial stem, Leaf, Underground stem, Root)
8. In Fabaceae the placentation is __________.
(Axile, Parietal, Marginal, Basal)
9. Plants that bear two types of spores are
called __________.
(Heterozygous, Homozygous, Homosporous,
Heterosporous)
10. Flagella are the organs, which help in
__________.
(Digestion, Locomotion, Photosynthesis,
Respiration)
11. Rhizopus is __________.
(A parasite, A saprophyte, Symbiotic,
Chemotrophic)
12. Rice belongs to the family __________.
(Cruciferae, Fabaceae, Poaceae, Solanaceae)
13. Potato is an example of __________.
(Bulb, Rhizome, Stem tuber, Corm)
14. Epigeal germination takes place in
__________.
(Gram seed, Castor seed, Maize seed, Rice)
15. Heterosproy is found in __________.
(Selaginella, Rhizopus, Ulva, Polytrichum)
16. The fusion of similar gametes in structure
and shape is called __________.
(Homospory, Isogamy, Oogamy, Anisogamy)
17. Virus is chemically composed of __________.
(Starch and Protein, Fat and nucleic acid, D.N.A
and lipids, Protein and Nucleic cid)
18. Streaming movement of cytoplasm in the cells
is called __________.
(Clycolysis, Cyclosis, Meiosis, Mitosis)
19. Incipient nucleus is found in __________.
(Ulva, Stegioclonium, Nostoc, Rhizopus)
20. The plant whose body is a mycelium is
__________.
(Euglena, Ulva, Rhizopus, Chlamydomonas)
21. In Marchantia elators are found in
__________.
(Gamma cup, Assimilatory chamber, Rhizoids,
Capsule)
22. Winged pollengrain is characteristic of
__________.
(Solanum tuberosum, Zeamays, Pinus, Brassica
Compestrics)
23. The modification of stem in ginger is called
__________.
(Sucker, Tuber, Bulb, Rhizome)
24. Vascular tissue system is found in
__________.
(Marchantia, Adiantum, Rhizopus, Ulva)
25. Fusion of similar gametes is called
__________.
(Oogamous, Isogamous, Heterosporous,
Homosporous)
26. __________ of the following pair belongs to
vascular plants.
(Funaria and Ulva, Ulva and Rhynia, Euglena and
Nostoc, Selaginella and Rhynia)
27. Verticellaster inflorescence is found in
__________.
(Fabaceae, Labiatae, Solanaceae, Poaceae)
28. __________ deals with the structure,
composition and function of the cells.
(Physiology, Anatomy, Cytology, Histology)
29. Reproduction by binary fission occurs in
__________.
(Bacteria, Euglena, Virus, Nostoc)
30. The membrane surrounding the vacuole is
known as __________.
(Tonoplast, Leucoplast, Chromoplast,
Chloroplast)
31. The ribosomes are the centres of __________.
(carbohydrate synthesis, Fat synthesis, DNA
synthesis, Protein Synthesis)
32. In lily plant the stem is modified into
__________.
(Rhizome, Bulb, Stem tuber, Corm)
33. In Chlamydomonas the chloroplast is
__________.
(Cup-shaped, Girdle-shaped, Disc-shaped,
Band-shaped)
34. Hypogeal germination occurs in __________.
(Cucumber, Castor, Papaya, Gram)
35. The most primitive vascular plant which
lived 40 million years ago was _________.
(Marchanita, Stigeoclonium, Rhynia, Selaginella)
36. The alternation of generations in Ulva is
__________.
(Heteromorphic Isomorphic, Isoheteromorphic,
Dimorphic)
37. Reproductive bodies, the gammae are found in
__________.
(Marchantia, Selaginella, Pinus, Potato Plant)
38. Dwarf shoots are spurs are found in
__________.
(Pinus, Selaginella, Stigeoclonium, Eucalyptus)
39. Feathery stigma is present in the family
__________.
(Brassicaeae, Poaceae, Solanaceae, Fabaceae)
Botany
Fill in the Blanks - XI Karachi Board
1. Chloroplasts are __________ green in colour.
2. Phycocyanin pigment is found in __________.
3. The pollination that takes place by water is
known as __________.
4. The male sex organ in Bryphyta is know as
Antherridium.
5. Petals are the component parts of __________.
6. In Chlamydomonas the chloroplas is __________
shaped.
7. A carpel consists of stigma, style and
__________.
8. A fruit that develop purely from ovary is
said to be simple fruit.
9. Chloroplasts are the centres of __________
synthesis.
10. A phage is a virus that infects __________.
11. Chloroplast is __________ in Cyanopyceae.
12. The pollen grains of __________ are winged.
13. Ribosomes are the centres of __________
synthesis.
14. Viruses are __________ obligate parasites.
15. The plants, which cannot synthesize their
own food materials, are called _________ heterotrophic plants.
16. The word virus is derived from the Latin
word. It means __________.
17. The collection of Hyphae is called
__________.
18. In Bryophyte water is absorbed through
__________.
19. The branches in Pinus are __________.
20. The plant body of Stigeoclonium is
__________.
21. A sexual reproduction in Chalamydomanas
takes place by means of motile cells called __________.
22. Pinus is an example of __________.
23. Alternation of generation in Ulva is
__________.
24. Pollination by wind is called __________.
25. Stames and carpels are modified __________.
26. Thread-like structures in nucleus are called
__________.
27. The germinating pollen grain is a tiny male
__________.
28. Fleshy fruits are dispersed by __________.
29. __________ is a food storage tissue.
30. Pitcher plant is the modification of __________.
31. Carpal is regarded as __________ female
reproductive system.
32. Leaf Spine reduces the rate of __________.
33. Brassica compestris is a member of family
__________.
34. Component parts of Calyx are called
__________.
35. Fabaceae family has __________ placentation.
36. Bulbil is a modification of __________.
37. Eye spot is found in __________.
38. Solanum tuberosum belongs to the family
__________.
39. In castor seed the papery cotyledons are
surrounded by __________.
40. Glumes are found in the family __________.
41. After fertilization ovule changes into
__________.
42. D.N.A is the abbreviation of __________.
43. In Nepenthes the leaf is modified into a
structure called __________.
44. Plant cell is surrounded by a cell wall,
which is made up of a __________.
45. The percentage of carbohydrates present in
the protoplasm is only _________.
46. In maize grain the cotyledon is known as
__________.
47. Ulva is also called __________.
48. The sporophyte of Marchantia consists of
foot, setae and __________
49. The inflorescence with dense cluster of
flowers on a receptacle is called _________.
50. In castor seed a cup like outgrowth at the
micropyle end is known as _________.
51. The plant which has 2n chromosomes is called
__________.
1- CAESAL
PINIOIDEAE/CASIA FAMILY
CLASSIFICATION
* DIVISION : ANGIOSPERMS
* CLASS : DICOTYLEDON
* SUBCLASS : POLYPETALAE
* SERIES : CALCIFLORAE
* ORDER : ROSALES
* FAMILY : LEGUMINOSAE
* SUB-FAMILY : CAESALPINIOIDEAE OR
CAESALPINIACEAE.
GENERAL
CHARACTERS
Majority of these plants are trees or shrubs,
about 135 genera and 5800 species are known .
VEGETATIVE
CHARACTERS
ROOT
Usually, Taproot with nodules and primary,
secondary and tertiary divisions.
STEM
Usually, Climbing stem or erect herbaceous
or woody, Some plants show xerophytic character.
LEAVES
Usually, Compound leaves bipinnate,
stipulate.
INFLORESCENCE
Usually, Racemose.
FLORAL CHARACTER
Usually, Complete, bisexual, perigynous, zygomorphic,
pentamerous.
CALYX
5 sepals, polysepalous, imbricate or valvate,
Green in colour.
COROLLA
5 petals, poly petalous, imbricate aestivation.
ANDROECIUM
Usually, 10 stamens, polyanderous, exerted,
extrose.
GYNOECIUM
Usually Monocarpillary, perigynous,
placentational marginal, unilocular with many ovules.
FLORAL FORMULA
+ , Q , K(5) , C(5) , A10 , G1/
POLLINATION
Usually, Cross pollination by insects
(entomophilly)
SEEDS
Usually, Both endospermic and non-endospermic.
FRUIT
Legume pod.
ECONOMICAL
IMPORTANCE
MEDICINAL PLANS
* Amaltas
* Kachnar
* Tamarindus Indica
* Panwar. e.t.c.
ORNAMENTALS
* Parkinsonia
* Gul-e-mohar
* Cacia sophera
DYES AND STAINING
Haemotoxylin is obtained from haemotoxylon
campechianom.
EDIBLE FRUIT
* Lomentum (Imli)
FIBER
Suitable fiber for paper making is obtained from
parkinsonia Aculeata.
FAMILIAR PLANTS
Botanical name............Common
Name...............Local Names
1-Tamarindus
indica.........Tamarind.................Imli
2-Cassia fistula............Amaltus.
3-Bauninia verigata.........Camel’s
foot.............Kachnar
4-Poinciana regia...........Flame of Forest
.........Gul-e-Mohar
5-Parkinosia roxburgai......VilayatiKikar
FLORAL DIAGRAM
(From Book)
2
MIMOSACEAE
ALTERNATE NAME
It is also known as “Acacia family”.
CLASSIFICATION
* DIVISION : ANGIOSPERMS
* CLASS : DICOTYLEDON
* SUBCLASS: POLYPETALAE
* SERIES : CALCIFLORAE
* ORDER : ROSALES
* FAMILY : LEGUMINOSAE
* SUBFAMILY : MIMOSACEAE / ACACIA
GENERAL CHARACTERS
It is the smallest group among the 3 groups of family
legume. It contains about 40 genera and 1450 species.
HABITAT
Mostly plants are distributed in tropical and
subtropical regions. Great variation inhabit, usually these trees are perinial
or binnial shrubs, some are herbs and climbing.
VEGETATIVE CHARACTERS
1. ROOT
Usually, Tap root with side branches, nodules
are present.
2. STEM
Usually, Erect and woody stem, rarely
herbacious, tannin and gums may also present.
3. LEAVES
Usually, Compound, bipinnate, stipule are
modified into spines. In many plants leaves show sleeping movement or after
having a shock.
INFLORESCENCE
Mostly, racemose.
FLORAL CHARACTERS
Usually, Complete, bisexual actinomorphic,
perigynous, pentamerous.
1. CALYX
Usually, 5 sepals, gamosepalous, valvate.
2. COROLLA
Usually, 5 petals, polypetalous, valvate
aestivation, small size.
3. ANDROCEIUM
Usually, numerous stamens, exerted, extrose,
basifixed anther.
4. GYNOECIUM
Usually, Monocarpillary, perigynous, unilocular,
placentation marginal, many ovules in locule.
POLLINATION
Usually, cross pollination by insects
(entomophilly).
SEEDS
Usually, Non-endospermic or with very little
endosperm.
FRUIT
Usually, It is called legume.
FLORAL FORMULA
+ ,Q , K(5) , C(5) , Aα , G1/
ECONOMICAL IMPORTANCE
1.WOOD YIELDING PLANTS
e.g-prosopis
* Acacia species
* Albizzia
* Xyliaet
2. ORNAMENTALS
e.g-Mimosa pudica (chuimoi)
* Austratian Acacia
* Neptunia
3. FOODER
From leaves of prosopis,
* Acacia
* Dicrostachys e.t.c.
4. SOAP POPS
Acacia concinna pods have (soponim), a substance
can be used as Soap.
5. CATECHU (KATHA)
Piece of hard wood
6. MEDICINAL USE
* Katha
* Siah Kanta
* Entada
* Acacia senegal
e.t.c.
7. GUMS & DYES
* Katha
* Safed Babul
* Sada Babul
IMPORTANT FAMILY MEMBERS
BOTANICAL NAME..............COMMON NAME................LOCAL
NAME
1-Acacia nilotica................Gum
tree.................Bauble, Kikar
2-Albizzia lebbek................Siris
3-Mimosa
pudica.................Touch-me-not..............Chhui mui
4-Prosopis glandulosa............Prosopis.................Dev
i
5-Acacia catechu.................Katha plant
FLORAL DIAGRAM
(FROM BOOK)
3- ROSACEAE
CLASSIFICATION
* Division
* Class
* Subclass
* Series
* Order
* Family: Rosaceae / Rose family.
GENERAL CHARACTERS
It has about 100 genera and 2000 species.
HABITAT
These plants are found growing all over the
world 213 species of about 29 genera are reported from Pakistan.
VEGETATIVE CHARACTERS
1. ROOT
Usually, Tap root with its usual branching.
2. STEM
Usually, Green herbaceous, cylindrical, small
spines are also present.
3. LEAVES
Usually, Simple leaves with or without petiole,
Opposite or alternate.
INFLORSCENCE
Usually Racemose
FLORAL CHARACTERS
Usually, Complete, bisexual, actinomorphic,
perigynous, pentamerous.
1. CALYX
Usually, Sometime epicalyx may also be present,
of variable number, 5 sepals are present, Gamosepalous, green, pubescent.
2. COROLLA
Usually, 5 petals or multiple of 5 petals,
polypetalous, aestivation, imbricate, shape-rosaceous, full of colour.
3. ANDROCEIUM
Usually, Nomerous stamen,ditheous, anther,
enerted, extrose, dorsi fixed.
4. GYNOECIUM
Usually, Monocarpillary or multiple capillary
with formation of a single compound pistil. Ovary perigynous, unilocular two or
more ovules are present, placentation axile when the carpels are many and
syncarpous
FLORAL FORMULA
+ , Q , K(5) , C(α) , Ax , G1/ (2-5) or x
ECONOMICAL IMPORTANCE
FRUIT
Economical importance of this family is great in
providing the pleasure and welfare of mankind. Plants of many famous fruits
belong to this family for e.g. Apple, pear, peach, e.t.c. Perhaps they rank 3rd
in commercial importance in the temperate, zone among the families of flowering
plants.
ORNAMENTALS
A large no. of ornamental plants of this family
are grown in parks and gardens the most widely cultivated plant for this
purpose is Rosa. Many others genera are also grown for their beautiful flowers
in homes and gardens.
OTHERS
Branches of crataegus and cotoneaster provide
excellent walking stick and wood. The wood of pyruspastia is used for making
tobacco pipes. In Asian countries rose petals are used in making Gul Khand and
are also used in extraction of an essential oil, Rose oil, used as perfume or
may be used as eye cleaner in certain diseases.
FAMILIAR PLANTS
BOTANICAL NAME...................COMMON
NAME..............LOCAL NAME
Malva
silvestis............................Apple........ ............Seb
Pyrus
pyrifolia............................Pear......... ............Nashpati
Prunus amygdalus...........................Almond........
............Badam
Rosa
indica................................Rose........ ..............Gulab
Prunus
persica.............................Peach......... ............Aru
FLORAL DIAGRAM
(FROM BOOK)
4-SOLANACEAE
ALTERNATE NAME
Night shade or Potato family
HABIT AND HABITAT
* It is widely distributed in temperate region
and very abundant in tropical countries.
* The plants are usually herbs or climbing vines
but may be shrub.
VEGETATIVE CHARACTERS
1-ROOT
Tap root and branched
2-STEM
Herbacious, erect or underground(Potato)
3-LEAF
Alternate in vegetative and opposite in floral
region
FLORAL CHARCTERS
1-INFLORESCENCE
Cyme sometimes helicoids
2-FLOWER
Pentamerous, Bisexual, Regular, Actinomorphic,
Hypogynous.
3-CALYX
Five, united sepals
4-COROLLA
Five petals, united, valvate aestivation
5-ANDROCIEUM
Five stamens, Inserted on Corolla
6-GYNOECIUM
Bicarpellary, Syncarpous (Carpels fused),
Placentaion axile.
7-FRUIT
Capsule Berry or Xanthium.
8-SEED
Minute with abundant endosperm.
FLORAL FORMULA
+ , O , K(5) , A5, C(5) ,
ECONOMIC IMPORTANCE
Members of this family provide drugs and food.
Some plants are poisonous and other are ornamental. This family is of great
economic importance as it provides food, fodder, drugs and ornamentals.
1-FOODER
* Solanum tuberosum (Potato)
* Lycopersicum esculentum (Tomato)
* Solanum melongena (Brinjal)
2-CONDIMENTS
* Fruit of capsicum
* Capsicum frutenscens
3-EDIBLE FRUIT
* Physalis (Cherry or Rasbhari)
4-DRUG YIELDING
* Atropa belladonna (atropine)
* Dotura (Daturine)
* Used in severe cold and in eye diseases.
* Sap of hanbane is used in dilating the pupils,
white cherry is used an nerve tonic.
5-ORNAMENTAL
* Cultivated in gardens
* Petunaia
* Nicotiana
* Cestrum Schizanthus
* Brunfelsia solanum
6-CIGARETTE MAKING
* Nicotiania tobacum (Tobacco)
IMPORTANT FAMILY MEMBERS
BOT-NAME........................COMMON
NAME.........................LOC-NAME
1-Solanum
Tuberosum..................Potato................. .............Aaloo
2-Solanum
Melongena..................Bringal................ .............Bengan
3-Lycoperscum
Escalentum.............Tomato..................... .........Temater
4-Capsicum
Annum.....................Red-Pepper..........................Lal-mirch
5-Petunia Alba.......................Petunia
6-Solanum Nigrum.....................Black Night
shade
7-Datura Alba........................Thorn apple
8-Nicotiana
Tobaccum.................Tobacco.................. ...........Tambako
9-Atropa Belladonna..................Deadly
night shade
10-Cestrum nocturnum.................Lady of
night.......................Raat ki Rani
FLORAL DIAGRAM
FROM TEXT BOOK (BIO-XI FAMILY SOLANACEAE )
5-FABACEAE
ALTERNATE NAME
* Papilionaceae or Pea family
HABIT AND HABITAT
Plants are herbs, shrubs or trees. Climbers,
aquatic plants or xerophytes. World wide distributed.
VEGETATIVE CHARACTERS
1-ROOTS
Tap root, branched bearing tubercle containing
nitrogen fixing bacteria.
2- STEM
Herbecious or woodi, erect or climber.
3-LEAF
Simple or commonly compound alternate, stipulate
FLORAL CHARACTERS
1- INFLORESCENCE
Racemose, rarely solitary.
2- FLOWER
Bisexual, irregular, zygomorphic, hypogynous.
3- CALYX
Five sepals, united
4- COROLLA
Five petals, usually free.
Corolla is papilionaceous (Butterfly shaped). In
this form the petals are 5, one of them is usually large and clawed. This petal
is called standard or “Vexillum” The two lateral ones, which are free are
called as “Wings” and two anterior inner most fuse to form a boat shaped
structure called the “Keel” or “Carina”.
5- ANDROCIEUM
Stamens (9) +1 i.e 9 fuse to form a round sheath
around the pistil while tenth is free.
6-GYNOECIUM
Monocarpellary, ovary unilocular, ovule numerous
on marginal placenta.
7-FRUIT
Legume or pod.
8-SEED
EX-albuminous.
FLORAL FORMULA
+ , Q , K(5) , C 1+2+(2) , A(9)+1 , G1
ECONOMIC IMPORTANCE
The family is of considerable importance, as a
source of high protein food, oil and forage as well as for ornamental purposes.
Chief importance lies in the pulses, belonging to this family. All types of
pulses (Dalls) are actually the seeds of this family which are rich in protein.
1- FOOD & FORAGE
* Cicer arietinum (Gram)
* Pisum sativum (Pea)
* Lens esculanta (Masure)
* Phaseolus aureus (Mung)
* Phaseolus mung (Urad/Mash)
* Phaseolus vulgaris (kidney bean/Lobia)
* Medicago sativa alfalfa (Lusan)
* Vicia
* Melilotus & Trifolium
2- FURNITURE & BUILDING PURPOSE
* Butea
* Dilburgia
3- OIL EXTRACTION
Arachis hypogea (Peanut/Moongphali)
4- DYES
* Indigofera tinctoria (Neel)
* Butea monosperma (Yellow dye)
5-MEDICINAL PURPOSE
* Glycyrrhiza glabra (Cough & cold
treatment)
* Clitoria termatea (Snake bite treatment)
6- ORNAMENTAL PLANTS
* Lathyrus
* Lupinus
* Clitoria
* Butea
* Abrus precatorious, used by jewellars as
weights called “Ratti”.
IMPORTANT FAMILY MEMBERS
BOT-NAME...................COMMON
NAME....................LOCAL-NAME
1- Lathyrus Odoratus...........Sweet
pea......................Matter
2- Arachis
Hypogea.............Peanut........................ .Moongphali
3- Cicer
Arietinum.............Gram........................ ...Channa
4- Dalbergia
Sisso.............Red-wood.......................Shesham
5- Pisum Sativum...............Edible pea
6- Sesbania aegyptica..........Sesbania
FLORAL DIAGRAM
FROM TEXT BOOK BIOLOGY-XI Pg # 191
6-POACEAE
ALTERNATE NAME
GRAMINAE/ GRASS FAMILY
HABIT AND HABITAT
* The species are most numerous in the tropics
but they are also abundant in temperate region.
* This family is monocot (one cotyledon in seed)
* Mostly annual or perennial herbs or shrubs.
VEGETATIVE CHARACTERS
1- ROOTS
Adventitious, fibrous or fascicled.
2- STEM
Cylindrical, Conspicuous nodes and hollow,
although solid stems are also found as sugar cane.
3- LEAF
Legulate, alternate leaf sheath mostly open
sessile, lamina narrow and ribbon shaped.
FLORAL CHARACTERS
1- INFLORESCENCE
Compound spikes.
2- FLOWER
Sessile, bracteate, incomplete, bisexual or
unisexual and zygomorphic.
3- PERIANTH
It is combined structure instead of calyx and
corolla. Number 2 or 3 membranous scales called “ Lodicules”
4- ANDROECIUM
Usually 3 stamens, filaments long, free anther
versatile.
5- GYNOECIUM
Tricarpellary, syncarpous though only one is
functional, unilocular, single ovule, style short 2-3, stigma feather like.
6- FRUIT
Grain or coryposis.
7- SEED
Endospermic, monocotyledonous.
FLORAL FORMULA
+ or O , O or O or O , P2 (lodicules) , A3 or 0
, G1 or 0
ECONOMIC IMPORTANCE
The family poaceae has great importance than any
other family of flowering plants.
1- FODDER AND FOOD STUFF
* Triticum indicum
* Avena sativa
* Zea mays
* Oryza sativa
* Hordeum vulgare
* Pennisetum typhoideum
2- SUGAR MAKING
Saccharum officinarum (sugar cane)
3-PAPER MANUFACTURING
Certain species of Grasses
4- VEGETABLES & SOUP DISH
* Sugar cane
* Bamboo-shoots
IMPORTANT FAMILY MEMBERS
BOT-NAME..............................COM-NAME.........................LOC-NAME
Triticum Indicum..........................Wheat............
................Gandum
Avena Sativa..............................Oats
Zea Mays..................................Indian
corn......................Makai
Oryza
Sativa..............................Rice.......... ...................Chawal
Saccharum Officinarum.....................Sugar
cane.......................Ganna
Hordeum
Vulgare...........................Barly........... .................Joo
Pennisetum Typhoideum.....................Bajra
Bambusa Arundinacea.......................Bamboo..........
.................Banns
Cymbopogon
Jawarancuza....................................... ..............Lemon Grass
Cynodon
dactylon.......................................... .................Lawn Grass
FLORAL DIAGRAM
FROM TEXT BOOK BIOLOGY-XI Pg#196)
DOUBLE FERTILIZATION
* After pollination, the tube nucleus of the
pollen grain forms pollen tube, while generative nucleus divides into two male
(sperm) gametes.
* When pollen tube reaches the embryo sac
through micropyle, one of the male gametes fuses w/t egg cell and forms
“oospore (zygote)”,it develops into seed. Another male gamete fuses with
definitive nucleus and forms “Endospermic nucleus”, w/c develop into endosperm
of seed or food storage tissue of seed.
* Because two times fertilization occurs so it
is called “Double fertilization”.
THE FLOWERS
The flower is a modified shoot and meant for
sexual reproduction. It is collection of four different kinds of floral
members, arranged in four separate whorls. The upper two whorls are essential
or reproductive whorls whereas lower two are helping or accessory whorls. The
flower is born on an axis which consists of two parts the pedicel or stalk of
flower and the thalamus is swollen end of the axis on which the floral leaves
are inserted. The floral whorls are arranged on the thalamus in a particular
order one just above the other. These four whorls are as follows.
CALYX
It is the first or lower most whorl of the
flower, the calyx is generally green is colour. Each member of calyx is known
as sepal. Sometimes sepals become coloured called petaloid. Such as in gold
mohur. The calyx is non essential or accessory part of flower.
FUNCTIONS
1- Protection of floral bud
2- Assimilation when green in colour
3- Attraction when coloured and showy
4- Modified into papus which helps in dispersal
COROLLA
It is the second non essential floral whorl of
flower. It is brightly colored. Each member of its known as petal. However
there is no differentiation of calyx and corolla in some flowers. It is called
perianth.
FUNCTIONS
1- The corolla attracts insects and hence help
in pollination.
2- It encloses stamens and carpels.
3- It protect the stamens and carpels from
external heat rain and insects attack.
ANDROCIEUM
It is the third essential floral whorl and each
member of it is known as stamen. The stamen is a male reproductive body and
consists of filament, anther and connective. The anther bears four chambers of
pollen sacs, each chamber is filled with granular mass of small cells called
pollen grains. Each pollen grain consists of two walls, the outer exine and
inner intine.
FUNCTIONS
It is the male reproductive body and hence
possess male gametes which take part in reproduction.
GYNOECIUM
It is the fourth essential floral whorl and its
component parts are called carpals. The carpel is a female reproductive body,
it may be one or more than one, and may be united or free. Each carpel consists
of stigma, style and ovary. The stigma is terminal end which receives the
pollen grain. It may be smooth or hairy and becomes sticky on maturity, The
style is slender projection of ovary, It helps in pollination and later on
dries up. The ovary is swollen basal portion, which encloses minute egg like
bodies called ovules. The ovule possess egg cells.
FUNCTIONS
The gynoecium is a female reproductive body. It
possess the egg cells which take parts in reproduction.
AESTIVATION
It is the arrangement of floral whorls i.e. the
sepals or petals in a floral bud, it is of following types:
(A) VALVATE
The members of a whorl lie close to each other
and do not overlap e .g Calatropis.
(B) TWISTED
One margin of a floral whorl overlaps that of
the next one. It may be clockwise or anti clockwise e.g. China rose.
(C)VEXILLARY
When petals are five, two internal are overlaped
on both margins by two petals, these two are overlaped by a single largest
posterior petal e.g. Pea bean etc.
(D)IMBRICATE
When one of the sepal or petal is internal and
other external and each or remaining one is overlaped on one margin and it
overlaps the next one on other margin e.g Gold mohur .
A. Velvate.
B Twisted
C. Vexillary
D. Imtricate.
INSERTION OF FLORAL LEAVES ON THE THALAMUS
The floral leaves are inserted on the thalamus
in a particular order, it is of following types:
(A) HYPOGYNOUS
In some flowers the thalamus is convex or
conical and ovary occupies the highest position on it. However other floral
whorls are inserted below the ovary, such flower is known as hypogynous and
ovary as superior. E.g. Mustard.
(B ) PERIGYNOUS
In certain flowers thalamus forms a flattened
circular disc due to the fact that sises of thalamus grows up to the same
level. The apex of thalamus is in the middle of the disc at which gynoecium
develops, whereas at the rim or margin sepals, petals and androecium are
inserted. They are round about it and hence are called perigynous, such as in
pea. Sometimes the apex of thalamus grows up in conical shape as in raspberry.
Whereas in some cases the calyx forms a cup shaped structure called calyx tube
such as in wild rose.
(C) EPIGYNOUS
In some flowers the concave receptacle surrounds
the ovary and is fused with it. The sepals, petals and stamens apparently arise
from the tip of the ovary such ovary is said to be inferior. E.g. Sunflower,
apple, guava, pear etc.
IMPORTANT TERMS TO DESCRIBE A FLOWER
COMPLETE :When all the four floral whorls are
present.
INCOMPLETE :When any of the whorl is absents.
BISEXUAL :The stamen and carpel both are
present.
UNISEXUAL :The flower possess either stamen or
carpel.
STAMINATE 
nly stamens are present (male).
PISTILATE :When flower possess only carpels
(female).
NEUTER :The stamens and carpels both are absent.
SYMMETRY
+ACTINOMORPHIC
When a flower can be divided into two equal
halves by any vertical section passing through centre.
+ ZYGOMORPHIC
When it can be divided into two similar halves
by only one vertical section.
+ IRREGULAR
The flower can not be divided into two similar
halves by any vertical plane.
COHESION OF STAMEN
+ MONOADELPHOUS
When filaments are united in a bundle and
anthers are free e.g. China rose.
+ DIADELPHOUS
The filaments are united into two bundles and
anthers are free e.g. Pea.
+ POLYADELPHOUS
The filaments are united into more than two
bundles and anthers are free.
+ SYNGENECIOUS
The anthers are united together and filaments
are free e.g. Sunflower.
ADHESION OF STAMENS
+ EPIPETALOUS
The stamens adhere to corolla, wholly or
partially by their filaments.
+ GYNANDROUS
When stamens adhere to carpels e.g. Calatropis.
LENGTH OF STAMENS
+DIDYNAMOUS
The stamens are four, two of them short and two
long e.g. Nerium.
+TETRADYNAMOUS
The stamens are six but two short and four long
e.g. mustard.
GYNOECIUM
+ MONOCARPELLARY
The pistil consists of only one carpel, it is
also known as simple pistil e.g. Pea, Bean
+ POLYCARPELLARY
The pistil consists of two or more carpels, it
is also known as compound pistil e.g. Rose.
+ SYNCARPOUS
The carpels are united into one ovary e.g.
Mustard.
STIGMA
+ CAPITATE
When stigma is rounded and knob like. Bi, tri or
Multified: when stigma is branched into two , three or many.
+ FEATHERY
When stigma is feather like.
+ FLATTENED
When sitgma is flat.
+ POINTED
When stigma is pointed.
+ LINEAR
When it is long and narrow.
STYLE
+ TERMINAL
When style arise from top of ovary; such as in
Mustard.
+ GYNOBASIC
When it arise between the lobes of the ovary
from its base;such as in Salvia.
+ PEDICILLATE
When flower is born on a stalk or pedicel.
(STALKED)
+ SESSILE
When stalk is absent
+ BRACTEATE
When flower is developed in the axil of a bract
+ EBRACTEATE
When bract is absent.
+ DIMEROUS
When each floral whorl has two floral leaves
(Dicot)
+ TRIMEROUS
When floral whorl has three floral leaves
(Monocot)
+ TETRAMEROUS
When each floral whorl has four floral leaves;
and so the pentamerous Dicots)
CALYX
+ PETALOID
The calyx having other then green colour.
+ CAMPANULATE
Sepals fused to form bell shaped structure.
+ POLYSEPALOUS
When sepals are free from one another.
+ GAMOSEPALOUS
When sepals are fused or united with one
another.
PETALS
+SEPALOID
The petals are green in colour.
+CRUCIFORM
Petals are arranged in form of a cross.
+POLYPETALOUS
When petals are free from one another.
+GAMOPETALOUS
When petals are united with one another.
+PERIANTH
When calyx and corolla can not be distinguished
with one other due to similar shape and colour.
PERIANTH
+SEPALOID
When perianth leaves are green.
+POLYPHYLLOUS
When perianth leaves are free from one another.
+GAMOPHYLLOUS
When perianth leaves are fused.
FLORAL FORMULA
The floral formula is represented by various
symlols. The symbols used in floral formula are as follows.
SYMMETRY OF THE FLOWER
* Zygomorphic = +
* Actinomorphic = O
SEXUALITY
* Bisexual = Q+
* Unisexual (male)
* Unisexual (female)
* Neuter =
PERIANTH
* Perianth = P
* Polyphyllous = Pn n=number of perianth leaves.
* Gamophyllous = (n) “ “ “
CALYX
* Epicalyx = Epi K
* Petals = C
* Calyx = K
* Polypetalous = Cn,
* Polysepalous = Kn, n= number
* Gamopetalous = C(n)
* Gamosepalous = K (n) of sepals
ANDROECIUM
* Androecium = A
* Androecium free = An n= number of stamens
* Androecium United = A (n)
* Epipetalous = C-A
GYNOECIUM
* Gynoecium = G
* Apocarpous = Gn
* Syncarpous = G (n)
* Ovary inferior = G
* n= number of carpels
* Ovary Superior = G
FLORAL DIAGRAM
The features of flower in flora formula are represented
by symbols, while in floral diagram by the diagram of its various floral leaves
alongwith actual number and position.
MOTHER AXIS: It is represented by a Dot above
the floral diagram. It actually shows the position how a flower is born. The
position of it can be seen from upperside. It may be between two adjacent
sepals or a single sepal.
PLACENTATION
It is the arrangement of placenta which are
cushion like ridges in the ovary, The placenta bear ovules. In simple ovary
placentaion is marginal, whereas in compound ovary it may be parietal, axile,
free central, basal and superficial.
(A) MARGINAL
In a simple ovary or monocarpellary pistil, the
ovules are arranged along the fused margins, these margins forms a cushion like
tissue called placenta along the ventral suture on the inner surface of ovary
wall e.g. Pea, Gram, Bean, etc.
(B) PARIETAL
In a compound syncarpous and unilocular ovary,
the fused margins of the carpals swells up to form placentas, to which ovules
are attached. The placentas lie along the wall of ovary and their number
indicates the number of carpels forming ovary e.g. cucumber, Melon; etc.
(C) AXILE
In a polycarpellary syncarpous pistil and
multilocular ovary, each carpel is folded along its mid-rib and meets in the
centre of the ovary. The ovules are attached to this central axis e.g. Tomato,
China rose, etc.
(D) FREE CENTRAL
In a compound and unilocular ovary the ovules
are situated all around the central axis, which arise from the thalamus and not
fused with the margins of the carpels. However in some plants the axile
placentation becomes free central due to breaking down of septa e.g. Pink
(Diantus)
(E) BASAL
In a unilocular ovary the placentas develops
directly on the thalamus and bears single ovule at the base of ovary e.g.
Sunflower, Cosmos etc.
(F) SUPERFICIAL
In a multilocular ovary, the ovules are not on
the margins of the carpels; but over the whole inner surface of the partition
walls e.g. Waterlily.
TYPES OF PLACENTATION
1.FOR SIMPLE OVARY
Only one type, MARGINAL.
2.FOR COMPOUND OVARY
I- Exile
II- Central
III- Parietal
IV- Basal
V- Superficial.
1. MARGINAL PLACENTATION
In marginal placentation, the ovary is one
chambered and the placenta develops along the junction of the two margins of
the carpel, called the ventral suture.
EXAMPLES
Pea, wild pea, gram, gold mohr, and cassia are
common examples.
2. AXILE PLACENTATION
In the axile placentation the ovary is two to
many chambered and the placenta bearing the ovules develop from the central
axis e.g. Potato, Tomato, Petunia, China rose etc.
3. CENTRAL PLACENTATION
In this case the septa in the young ovary soon
break down so that the ovary becomes one-chambered and the placenta develops
all round the central axis e.g. Dianthus, Saponaria etc.
4. PARIETAL PLACENTATION
The ovary is one chambered and placenta develops
on the inner wall of the ovary e.g. papaw, orchids etc.
5. BASAL PLACENTATION
The ovary is unilocular and placenta develops
directly on the thalamus e.g. sunflower, cosmos etc.
6. SUPERFICIAL PLACENTATION
The ovary is multilocular, carpels are numerous
and placenta develops all round the inner surface of the partition walls as in
waterlily.
INFLORESCENCE
The branch system of the floral region bearing a
group of flowers is called INFLORESCENCE. The term inflorescence refers to the
arrangement of flowers on plant.
TYPES OF INFLORESCENCE
The flowers may be solitary or grouped into
clusters, Such clusters vary in shape and arrangement. On the basis of
arrangement of flowers, inflorescence is classified into
1-RECEMOSE
1- In this case, the main axis of inflorescence
does not end in a flower.
2- Main axis continues to grow and gives off
flowers laterally.
3- The lower or outer flowers are always older
and open earlier than the upper or inner ones.
4- Order of opening of flowers is called
centripetal.
EXAMPLES
Mustard, Gold mohr, Mulberry, birch etc.
KINDS OF RECEMOSE INFLORESCENCE
Recemose inflorescence has following main types
on the basis of nature and shape of the peduncle:
I- PEDUNCLE ELONGATED
It is further subdivided into following types;
1. RECEME
The main axis in this case is elongated and it
bears laterally a number of flowers which are all stalk e.g. radish, mustard,
dwarf gold mohur etc.
2. SPIKE
In this case the flowers are sessile e.g.
Adhatoda, Achyrnthes etc.
3. CATKIN
This is a spike with a long and pendulous axis
which bears unisexual flowers e.g. Musberry, Acalypha, Birch and Oak etc.
4. SPADIX
This is also a spike with a fleshy axis which is
enclosed by one or more large bracts called spathes e.g. Banana, Palms etc.
II- PEDUNCLE SHORTENED
It is further divided into following types;
1. CORYMB
Here the main axis is comparatively short, and
the lower flowers have much longer stalk than the upper ones. Hence all the
flowers are brought more or less to the same level e.g. candytuft, wall flowers
etc.
2. UMBEL
Here the primary axis is short and it bears at
its tips a group of flowers which have pedicles of more or less equal length so
that the flowers are seen to spread out from a common point. In the umbel there
is always a whorl of bracts forming an involucre, and each flower develops from
the axil of a bract, e.g. Carrycumin, Coriander etc.
III- PEDUNCLE FLATTENED
The best example is seen in sunflower family,
here the inflorescence is called the head as the capitulum.
HEAD OR CAPITULUM
1. A dense cluster of sessile or sub-sessile
flowers, on a compound receptacle is called capitulum.
2. Main axis is almost flat, bearing sessile
flowers.
3. Outer flowers are older and open earlier.
4. The florets are commonly of two types
I- RAY FLORETS
II- DESC FLORETS
EXAMPLES
Capitulum is characteristic feature of sunflower
family e.g. sunflower, marigold; zinnia, cosmos etc.
IV- SPIKELET INFLORESCENCE
It is a kind of racemose inflorescence. There
are three bracts at its base called glumes. The lower two without flowers are
called empty glumes. The third glume has flower in its axil and called Lemma.
Just opposite to lemma, there is small bractcole called Palea. Flowers are covered
by their respective lemma and palea. This type of inflorescence is
characteristic feature of family Poaceae (Grass Family).
2-CYMOSE
1- Here the main axis ends in a flower and
similarly the lateral axis also ends in a flower.
2- The growth of each axis is checked due to
presence of flower on its tip.
3- The terminal flowers are always older and
open earlier than the lateral ones.
4- The order of opening of flowers is
centrifugal.
EXAMPLES
Jasmine, Teak, Night Jasmine, Ixora.
KIND OF CYMOSE INFLORESCENCE
I- UNIPAROUS (MONOCHASIAL) CYME
Main axis soon ends into a flower and produces
only one lateral branch at a time ending in a flower. The succeeding lateral
branches again follow the same mode of producing flowers. If the succeeding
branches are produced on alternate side, it is called Scorpiold cyme (cotton,
forget-me-not). Whereas, if the succeeding branches are produced on same side,
it is called Helicoid (sundew).
II- BIPAROUS (DICHASIAL) CYME
Main axis soon terminate into a flower and
produces two flowers. This mode is followed by each succeeding flowers (Pink,
Night- Jasmine).
POLLINATION
It is the process of transference of pollen
grains to the stigma of the flower.
TYPES OF POLLINATION
Pollination is of two types.
1- Self pollination or Autogamy.
2- Cross Pollination or Allogamy.
(A)SELF POLLINATION
It is the transfer of pollen grains from the
anther of a flower to the stigma of the same flower.
METHODS OF SELF POLLINATION
In self pollination, only one flower is
concerned to produce the offspring. Irrespective whether the flower is
unisexual or bisexual self pollination can take place by two methods
I-HOMOGAMY
In homogamy the anther and the stigma of a
unisexual flower mature at the same time. In rare cases it may takes place by
insects or wind.
II- CLEISTOGAMY
In cleistogamy the flower never open. They
remain closed and the pollination takes place in the closed flower such as in
pansy (viola), balsam (impatiens), oxalis, etc.
B)CROSS POLLINATION
It is transfer of pollen grain from the flower
of one plant to the stigma of flower of another plant of the same species.
METHODS OF CROSS POLLINATION
It takes place by external agencies. These
agents are insects, animals, birds, wind and water.
I- ENTOMYPHILY
The pollination takes place by insects. It is of
general occurrence in plants.
II ANEMOPHILY
The pollination is brought about by wind.
III HYDROPHILY
The pollination takes place in aquatic plants
particularly the submerged ones, through the medium of water e.g. Hydrilla and
vallisneria
IV ZOOPHILY
The pollination is carried out by birds,
squirrels, snails etc. Examples are Bombax and Erythrina.
Read more: Plant Families http://www.friendsmania.net/forum/1st-year-biology-notes/20537.htm#ixzz354tmjgJy
Kingdom
Plantae
Friendsmania.net
Kingdom Plantae
Friendsmania.net
INTRODUCTION
* Includes all eukaryotic multicellular and
chlorophyllous living organisms, which have cell wall made up of true
cellulose.
* Majority of members are autotrophic but few
are parasite e.g.: “Cuscuta”
* They have localized growth, regions of growth
lying primarily at the extremities that is root and stem apices.
CLASSIFICATION OF KINGDOM PLANTAE
Kingdom planatae is divided into tow sub-kingdom
on the basis of presence or absence of vascular tissue (xylem and phloem).
A - SUB-DIVISION - BRYOPHYTES (NON-VASCULAR)
* Class Hepatica (Liverworts)
* Class Musci (Mosses)
* Class Anthroccrota (Hornworts)
B- SUB-DIVISION - TRACHEOPHYTES
* Class Psilopsida (Psilopsids)
* Class Lycopsida (Club Mosses)
* Class Sphenopsida (Horse Tails)
* Class Pteropsida (Ferns)
* ClassSpermopsida (Seed Plants)
SUB –DIVISION BRYOPHYTA (AMPHIBIAN PLANTS) OR
(NON-VASCULAR PLANTS)
* Absence of lignin-fortified tissue to support
tall plants on land.
* Members of this sub-division usually sprawl
horizontally as mats over a large surface.
* Always have a low profile (1-2cm-20cm tall).
Regular heteromorphic alternation of generation
is present w/t gametophytes dominancy (Gametophytes large and long lived).
* Sporophyte stage of bryophytes is generally
smaller and shorter lived, and it depends on gametophyte for water and
nutrients.
* The diploid sporophyte produces haploid spores
via meiosis in a structure called “sporangium”
* The tiny, spores, protected by sporopollenim,
disperse and give rise to new gametophytes.
* All members of bryophytes need water to
reproduce.
* Gametes produce within reproductive structures
“Gametangia” (Male-Antheridia and Female-Archer-gonium)
* Antheridium produces flagellated sperm while
female archegonium contains one egg (ovum).
* Fertilization occurs w/t in the archegonium
* Zygote develops into an embryo within the
protective jacket of Archegonium.
* Windblown spores disperse the speies.
* All bryophytes belong to Silurian/Devonian
period (345-395Million yrs. Ago.)
ADAPTATION OF BRYOPHYTES TO LAND HABITAT
All Bryophytes show amphibious form of land
plants. Following are main adaptations exhibited by them.
a. Rhizoid for water absorption
b. Conservation of water
c. Absorption of CO 2
d. Heterogamy
e. Protection of reproductive cells
f. Formation of embryos
CLASSES OF BRYOPHYTES
1-MUSCI (MOSSES)
* Plants grow in a tight pack, in the form of
mat, in order to hold one another up.
* Mat of moss possess spongy quality and enables
it to absorb and retain water.
* Rhizoids are elongated cells or cellular
filaments of mats which grip the substratum.
* Photosynthesis occurs in upper part of the
plant w/c has many small stem like and leaf like appendages. E.g Funaria.
2-HEPATICAE (LIVERWORTS)
* Usually present in tropical areas
* Plant body is divided into lobes somewhat of
the lobed liver, of an animal.
* These plants are less fimiliar than Mosses.
* E.g Marchantia
3- ANTHROCERATAE:- (HORNWORTS)
* These plants resemble w/t liverworts, but are
differentiated by their sporophytes plants.
* Sporophyte are elongated capsules that grow
like horn from mat like gametophyte.
* Sporophyte has stomata and chloroplast,
performs photosynthesis
* Sporophyte plant can survive even often the
death of gametophyte due to presence of Meristem.
* Meristem is a specialized tissue, which keeps
on adding new cells in sporophyte plant.
* Hornworts are the most advanced members of
bryophytes.
* E.g Arthroceros
SUB-DIVISION TRACHEOPHYTA (VASCULAR PLANTS)
Main characters are as follow,
* Conducting vessels Xylem and Phloem are
present in plant body.
* A protective layer of sterile “Jacket” cells
around reproductive organs are present.
* Multicellular embryos retained within the
archegonia.
* On aerial parts protective covering “Cuticles”
is present w/c prevents excessive loss of water during hot climate.
* In life cycle Sporophyte stage is dominant.
CLASSES OF TRACHEOPHYTES
1-PSILOPSIDA
* These are the fossil representatives of the
vascular plants, belonging to “Silurain period” and “Devonian Period”
* Sporophytes are simple dichotomously branching
plants.
* True leaves and true roots absent.
* Underground stems that contain unicellular
rhizoid similar to root hairs.
* The aerial stems are green and carry out
photosynthesis.
* Lacking secondary growth due to absence of
“Cambium”
* Reproductive structure “Sporangia” develop at
the tips of some of the aerial branches.
* Meiosis produces haploid spores, within the
sporangia.
* E.g. Rhynia, Psilotum Temesipteris
A) RHYNIA (FIRST VASCULAR PLANT)
* One of the most primitive vascular plant
* It is an extinct genus, was named often the
village “Rhynia of Scotland where the first fossils of Rhynia were discovered.
* It belongs to Devonian period, which started
about 400 million years ago.
* The fossils of this plant are so well
preserved that the stomata are still intact.
STRUCTURE
* The plant body (Sporophyte) was simple.
* It consisted of slender, dichotomously
branched creeping rhizome, bearing erect, dichotomously branched aerial stem.
* Instead of roots, rhizoids were given out from
rhizome.
* The aerial branches were leaf-less having
terminal fusiform naked sporangia.
MICROSCOPIC STRUCTURE
* The internal structure of branches show a
solid central core of vascular tissues surrounded by Cortex.
* The outer most layer is Epidermis having
stomata.
* The vascular tissue is differentiated into
centrally placed xylem and surrounded phloem
(FIGURE 9.06(a) Reconstruction of Rhunia) TEXT
BOOK BIO-XI Pg# 170
B) PSILOTUM AND TEMESIPTERIS (LIVING SPECIES OF
PSILOPSIDA)
* Sporophyte plant produce spores, which give
rise to minute subterranean gametophytes.
* Each gametophyte bears both female
reproductive organ Archegonia and male reproductive organ Antheridia w/c
produce both egg and sperm respectively.
* As a result of fertilization a diploid zygote
is formed which develops into sporophyte plant.
* Sporophyte stage of life cycle is dominant,
but haploid gametoplyte stage is still relatively large.
EVOLUTION OF LEAF
The leaf is the most important organ of a green
plant because of its photosynthetic activity. Leaves are of tow types
1. Single veined leaves- Contain only one vein
2. Poly veined leaves- Contain two or more veins
1- EVOLUTION OF SINGLE-VEINED LEAF
* It is assuming that a thorn like out growth
emerged on the surface of the naked stem.
* With an increase in size of the leaf, the
vascular tissues were also formed for the supply of water and support to the
leaf.
* Another possibility is that a single veined
leaf originated by a reduction in size of a part of the leafless branching
system of the primitive vascular plants.
- EVOLUTION OF POLY-VEINED LEAF
* These are the evolutionary modifications of
the forked branching in the primitive plants.
* The first step in the evolution of this leaf
was the restriction of forked branches to a single plane.
* The branching system become flat.
* The next step in the evolution was filling the
space b/w the branching and the vascular tissues.
* The leaf so formed looked like the webfoot of
a duck.
(Fig#9.7-9.8From Text. Book)
2-LYCOPSIDA(THE CLUB MOSSES)
* These plants belong to middle Devonian and
carboniferous periods.
* They were very large trees that formed the
earth’s first forests.
* Only five living genera of this group are
present.
* Two members, selaginella and lycopodium are
common in many areas of Pakistan
* These plants have true branched underground
roots.
* True leaves also present w/c have arisen as
simple scale like outgrowth (emergence) from the outer tissues of the stem.
* Specialized reproductive leaves bearing
sporangia on their surfaces, are present, such type of leaves are known as
“Sporophylls”.
* In some members, the sporophylls are collected
on a short length of stem and form cone like structure “Strobilus”.
* The cone is rather club-shaped; hence name
“Club-Mosses” for the lycopsids.
* Gametophytes plant may be homosporous or
heterosporous .
A) HOMOSPOROUS GAMETOPHYTES
* Spores produced by sporophyte plant are all
alike, and each give rise to a gametophytes that bear both archegonia (female
reproductive structure) and antheridia (male reproductive structure)
* Example Lycopodium (Running pine or ground
pine)
B) HETEROSPOROUS GAMETOPHYTES
* Sporophyte (2n) plant produces two types of
sporangia, which produced different kinds of spores.
* One type of sporangium produces very large
spores called “Megaspores,” which develop in female gametophytes bearing
archegonia.
* Other type of sporangium produces small spores
called “Microspores, which develop into male gametophytes bearing antheridia.
* That’s mean sexes are separate in the
gametophytes generation (Heterosporous).
* Example: Selaginella.
EVOLUTION OF SEED
Seeds are evolved from primitive spores.
STEPS OF EVOLUTION
1. PRIMITIVE SPORES
All spores of specie are nearly identical in
size, structure and function.
2. HETEROSPORES
* There are many vascular plants that form two
kinds of spores, these plants are said to be “Heterosporous” and spores are
called “Heterospores.”
* These spores on germination give rise to two
different types of plants.
A) MALE SPORE: It produces sperm forming
gametophyte plant.
B) FEMALE SPORE: It grows into egg forming
gametophyte.
3. PROTECTION OF HETEROSPORES
* The two different kinds of spores are formed
in two different kinds of sporangia.
* Various enveloping structures develop in order
to protect these spores.
* Certain fern like plants first developed seed
like structures, each of their sporangia, containing one or more female spores,
was surrounded by little branch like out growth structure forming “Integument.”
4. PERSISTANCE OF FEMALE SPORES
* Instead of being shed from the sporangium, the
female spores are retained and protected inside the integument.
* The female spore develops into a tiny female
gametophyte protected by the integuments.
5. FORMATION AND STRUCTURE OF SEED
* Seed is formed as the result of fertilization
of male spore with this protected female spore.
* Immature seed is called “Ovule.”
* Ovule is protected by integuments and it
contains great quantities of food.
* Ovule not only protects the female gametophyte
from the environment but also provides food for the new off springs that is produced
when the seed matures and germinate. The development of seed has given the
vascular plants better adaptations to their environment.
3. SPHENOPSIDA (THE HORSE TAILS)
* These plants belong to late Devonian and
Carboniferous period.
* Only one living member “Equisetum” commonly
called “Horse-tail” exists today.
* Ancient sphenopsids were large trees but now
most of these are small (Less than one meter).
* Coal deposits of today was formed from the
dead bodies of those plants.
* These plants possess true roots, stems and
leaves.
* Stems are hollow and are jointed, whorls of
leaves occur at each joint.
* Secondary growth absent, because modern
species do not possess cambium.
* Spore are born in terminal cones (Strobili)
and all are alike (i.e. plants are homosporous) and give rise to small
gametophytes that bear both archegonia and antheridia (i.e. the sexes are not
separate).
4. PTEROPSIDA (THE FERNS)
* These plants belong to Devonian and
Carboneferous Period and then decline in Paleozoid Period.
* They are very well developed plants having
vascular system with true roots, stem and leaves.
* Leaves are probably arisen from flattened web
branched stems. They are large and provide much greater surface area for
photosynthesis.
* Leaves of Ferns are sometimes simple, but more
often they are compound, being divided into numerous leaflets.
* In most modern ferns of temperate regions, the
stems are prostrate on or in the soil, and the large leaves are only part
normally seen.
SPOROPHYTIC STAGE
* The large leafy plant (fern) is diploid
sporophytic phase.
* Spores are produced in sporangia (Reproductive
structure) located in clusters on the underside of some modified leaves
“Sporophyll.”
* Most modern ferns are homosporous i.e. all these
spores are alike.
* Vascular sporophytes can live in drier places
and grow bigger.
GAMETOPHYTE STAGE
* After germination, the spores develop into
gametophytes that bear both archegonia and antheridia.
* These gametophytes are tiny (less than one
centimeter wide), thin and often more or less heart-shaped.
* Free-living, non-vascularized gametophytes can
survive only in moist places, their sperms are flagellated and water is
required for fertilization.Young sporophyte develops directly from the zygote
without passing through any protected seed like stage.
(LIFE CYCLE OF FERN-TEXT BOOK PAGE # 166 NEW
ADDITION)
ALTERNATION OF GENERATION
* In Kingdom Plantae, life cycle of many plants
is completed in two stages or generations known as Gametophyte and Sporophyte.
* The two generations normally differ from each
other in morphology, reproduction and number of chromosomes.
* The gametophyte is haploid and reproduces
sexually by forming the gametes, while the sporophyte is diploid and reproduces
a-sexually by forming the spores.
* The two generations regularly alternate with
each other and therefore, the phenomenon is called “Alternation of generation”
(Heteromorphic).
* In Bryophytes, the main plant itself is the
Gametophyte while the sporophyte is reduced.
* In Tracheophytes, the main plant is
“Sporophyte” and the “Gametophyte” is reduced.
5. SPERMOSIDA (THE SEED PLANTS)
* First appeared in late Devonian and became
dominant in Carboniferous Period.
* Gametophyte stage is even more reduced than in
the ferns, and non-photosynthetic or free-living.
* The sperms of most modern species are not
independent free-swimming flagellated cells.
* Young embryo, is enclosed within a seed coat
and can remain dormant for long periods.
* Spermosida can be divided into two main
sub-groups, which are as follows:
i) Gymnosperms
ii) Angiosperms
I) GYMNOSPERM
* These plants have naked seed because ovules
are not covered by ovary i.e. fruit is absent.
* Sub-divisions of Gymnosperms are
a) Cycads
b) Gnetae
c) Ginkgo
d) Conifers
A) CYCADS'
* They have arisen from the seed ferns.
* These plants appeared in “Permian Period” and
Mesozoic Period and declined in Cretaceous Period.
* They possessed large palm like leaves with
short height stems.
* Living species commonly found in tropical
regions and also known as “Sago Palms.”
* Nine living genera with over a hundred species
exist today.
* Cycads and its relatives.
B) GINKGOAE'
* Mostly contains extinct species, only one
living specie, “the Ginkgo” which is also known as “Maiden Hair Tree.”
* Ginkgo often planted as lawn tree.
* E.g: Ginkgo Biloba.
C) CONIFERS
* Most familiar and best-known group of
gymnosperms.
* Leaves are small evergreen needles or scales
with an internal arrangement of tissues.
* Reproductive organs are cone like modified
leaves.
* E.g: Pinus.
PINUS
This plant belongs to Gymnosperms. It includes
about 90 species.
HABIT AND HABITAT
* It is distributed world-wide mostly in
northern hemisphere. 30 species are found in the Himalayas. Some are reported
in the planes of Punjab.
MORPHOLOGY
* The pinus plant belongs to the “Sporophytic
Phase.”
* It is a tall tree, pyramidal in form and gives
a conical appearance and therefore commonly grouped under “Conifers.”
* It is well differentiated into stem, root and
leaves.
STEM
It is erect, cylindrical, solid and covered with
thick, rough and brownish bark. The branches are dimorphic,
* Branches of unlimited growth or long shoot.
* Branches of limited growth or dwarf shoot.
ROOTS
Underground root system is formed by “Tap Roots”
which disappear early and only lateral roots persist later on.
LEAVES
It bears two types of leaves (dimorphic
condition)
a) Scale leaves
b) Foliage leaves
A) SCALE LEAVES
* Thin, membranous small scale like structures.
* Provide protection and do not help in
photosynthesis.
B) FOLIAGE LEAVES
* Only develop on dwarf shoots.
* Number of foliage leaves is fixed for
particular specie.
* Each leave is needle shaped, simple green
therefore also known as “Needles.”
* They have smooth surface and are evergreen and
persistent.
LIFE CYCLE OF PINUS
* The adult plant of Pinus represents the
“Sporophytic Phase” of life cycle.
* The sporophytic plant body of pinus reproduces
asexually by means of spores and after passing through “Gametophytic Phase” of
the life cycle again produce Sporophytic plant, showing distinct Alternation of
Generation.
1. SPOROPHYTIC PHASE
* The sporophytic plants of Pinus are mostly
monoecious i.e. male and female cones are found on same plant.
* Special reproductive organs called “Cones,”
developed on it.
A) MALE CONE OR O-STROBILUS
* The male cones occur in clusters near the end
of long branches at the place of dwarf shoot. (Dwarf shoots are replaced by
male cone).
* Each male cone is simple ovoid structure 3-4
cm in length.
* It has got single centrally located cone axis
around which are arranged spirally, many scaly microsporophylls (60-135).
* Each microsporophyll has an expanded triangular
central part and a stalk like base.
* Each microsporangium, which is born on the
lower side bears numerous “Pollen grain mother cells.”
* When the microsporangium matures, on its lower
side a horizontal slit is formed through which numerous Pollen grains are
liberated and dispersed by wind.
* Each pollen grain is winged structure and
yellow in colour.
B) FEMALE CONE OR O-STROBILUS
* The female cones are developed laterally in
the axis of scale leaves.
* The female cones are much bigger, woody, dry
and hard structure.
* The young female cone is reddish green
structure. Each female cone consists of a central axis to which are attached
the “Megasporophyll.”
* Each megasporophyll on its surface has two
ovules.
* Each ovule is orthosporous and consists of a
central mass of tissue, surrounded by a single integument, made up of 3 layers.
* The integument bears a wide gap, the
microphyle.
* Within the megasporangium, megaspore mother
cells are present, which undergoes reduction division to produce a “Megaspore.”
* Only one megaspore is functional, however the
other three degenerate.
2. GAMETOPHYTE PHASE
* The spores are the units of gametophytic phase
of life cycle.
* In case of Pinus the spores are of two types,
microspores and megaspores.
A) MALE GAMETOPHYTES
* Microspore is a unit of male gametophyte.
* Each microspore or pollen grain is a
unicellular body, covered with an outer layer, “Exine,” thick and heavily
culticularized, while the inner layer, the “Intine” is very thin.
* The Exine forms the balloon shaped wings on
either side, which help in pollination.
* The microspore is at this, four celled stage
(consisting of one generative cell and two prothalial cells and a tube cell).
B) FEMALE GAMETOPHYTE
* The Megaspore is the first cell of female
gametophyte.
* The functional megaspore increases in size and
forms a complete cellular female gametophyte, also known as “Endosperm.”
* The “Archegonia” are formed towards micropylar
side.
* The cells of the endosperm or Archegonia
initial cell divides and forms the central cell.
* The central cell forms the venter canal cell
and a large egg cell.
POLLINATION
In case of Pinus, Pollination is effected by
wind (Anemophyllous).
FERTILIZATION
1. The pollen grains reach the apex of the
Archegonium.
2. The pollen tube carrying the two male gametes
and the tube nuclei comes in contact with the archegonium.
3. The tip ruptures, discharging its contents
into the egg.
4. One of the male gamete fuses with the egg
nucleus and unites forming the oospore or zygote.
5. The second male gamete along with the tube
and tube nuclei disintegrate.
PINUS SEED
* Fertilized ovules get transformed into seeds.
* Seeds are small elongated and winged.
GERMINATION OF SEED
The seed undergoes into a condition of dormancy
when the conditions are favourable, the seed absorbs moisture and the embryo
resume growth.
STRUCTURE OF OVULE
* Ovules are female part of flower, form seed
after fertilization.
* Microscopic study of an ovule reveals following
structural features of an ovule.
1. FUNICLE
It is slender stalk of ovule through which it
attaches to the placenta.
2. HILUM
It is the point of attachment of the body of the
ovule to its funicle.
3. RAPHE
In the inverted ovule, the funicle continues
beyond the hilum along side of the body of the ovule forming a sort of ridge,
which is called the “Raphe.”
4. CHALAZA
The distal end of the raphe, which is the
junction of integuments and the nucellus is called the “Chalaza.”
5. NUCELLUS
It is the main body of ovule.
6. INTEGUMENTS
Nucellus is surrounded by two coats called the
“Integuments.”
7. MICROPYLE
It is the small opening at the apex of
integuments.
8. EMBRYO-SAC
It is a large, oval cell lying embedded in the
nucellus towards the micropyle end. It is the most important part of the ovule
as it bears the embryo. It is further developed, and in the mature embryo sac
following cells can be seen:
A) EGG APPARATUS
* It is the group of three cells lying towads
the micropyle.
* One cell of the group is the female gamete,
the ovum/egg, and the other two are called “Synergids.”
* The ovum or egg-cell on fertilization gives
the embryo, synergids get disorganized soon after fertilization.
B) ANTIPODAL CELLS
This is the group of three cells lying at the
opposite end of egg apparatus. These have no definite function.
C) DEFINITIVE NUCLEUS
In the middle of the embryo-sac there is a
distinct nucleus known as a definitive nucleus, which is the fused product of
the two polar nuclei.
STRUCTURE OF POLLEN GRAIN
* Pollen grains are male part of flowers, and
are contained in the “Pollen-Sac.”
* They are very small in size, usually varying
from 10 to 200 μm.
* Microscopic study of a pollen grain shows
following features:
1. EXINE
* It is the outer coat of the pollen grain.
* It is tough, cutinized layer, which is often
provided with spinous out growths or markings of different patterns, sometimes
smooth.
* It has one or more weak slits or pores called
“Germopores.”
2. INTINE
* It is the inner coat of the pollen grain.
* It is thin, delicate, cellulose layer lying
internal to the exine.
* During fertilization in time grows to form
pollen-tube.
3. INTERNAL STRUCTURE
* Each pollen grain contains a bit of cytoplasm
on a nucleus.
* During germination of pollen grain nucleus
further divides to form a “Tube Nucleus,” and a smaller one the “Generative
Nucleus.”
* The generative nucleus soon divides into two
male gametes.
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Summary of Kingdom Anamalia
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INDEX
* 1 (1) PHYLUM PORIFERA
* 2 (2) PHYLUM CNIDARIA
* 3 (3) PHYLUM PLATYHELMINTHES
* 4 (4) PHYLUM ASCHELMINTHES (NEMATODA – ROUND
WORMS)
* 5 (5) PHYLUM ANNELIDA (SEGMENTED WORMS)
* 6 (6) PHYLUM MOLLUSCA (SOFT BODIED ANIMAL)
* 7 (7) PHYLUM ARTHROPODA ( JOINTED LEGS)
* 8 (8) PHYLUM ECHINODERMATA (ANIMAL WITH SPINY
SKIN)
* 9 (9) PHYLUM HEMICHORDATA (ANIMAL WITH HALF
NOTOCHORD)
* 10 (10) PHYLUM CHORDATA
* 11 GROUP ACRANIATA
* 12 GROUP CRANIATA OR VERTEBRATA
* 13 1. SUPER - CLASS PICSES (FISHES)
* 14 2. SUPER CLASS TETRAPODA
* 15 1. CLASS AMPHIBIA
* 16 2. CLASS REPTILIA
* 17 3. CLASS AVES (BIRDS)
* 18 4. CLASS MAMMALIA
(1) PHYLUM PORIFERA
* Porous body
* CaCO3 Silica Skeleton
* Asymmetrical
* Amphiblastula larva
* Diffuse cellular organization
* Spongocoel body cavity
(2) PHYLUM CNIDARIA
* Radially symmetrical
* Body cavity “Coelentron”
* Pnedoblast – Defensive cells
* Diploblast (Ecto + Endoderm)
* Middle non-cellular layer “Mesoglea”
* Larva – Planula Larva
* Morphologically
a- Medusa = Umbrella like
b- Polyp = Rod shaped
(3) PHYLUM PLATYHELMINTHES
* Flatworms
* Totally Parasite
* Flat or Ribbon shaped
* Excretory organs – Proto nephridia (Flame
cells)
* Aeoelomate (Absence of body cavity)
* It is the first phylum containing triplo
blastic animals
* Usually Hermaphrodites
* Planaria is the only free living member
* High fertility rate
* Bilaterally Symmetrical
(4) PHYLUM ASCHELMINTHES (NEMATODA – ROUND
WORMS)
* Totally parasitic including 50 human parasite
* Bilaterally symmetrical with cylindrical body
* Two openings (Mouth & Anus)
* Psudocoelomates
* Common diseases – Ascariasis, filiariasis
(elephantiasis), hook worm infection.
(5) PHYLUM ANNELIDA (SEGMENTED WORMS)
* Metamers (External segmentation)
* Septae (Internal segmentation)
* Setae (Locomotary organs) or cheata
* Digestive, excretory, nervous, reproductive
system well developed.
* Respiration through diffusion
* Blood is red with a closed type of circulatory
system (with many pulsatile hearts)
CLASS POLYCHEATA
* Setae with Parapodia
* Separate sexes
* Sabella (Peacock worm), Nereis (Clam worm)
CLASS OLIGOCHEATA
* Setae without Parapodia
* Pheretima (Earth worm)
CLASS HIRUNDINIA (LEACHES)
* Free living, Ecto or Endo parasite
* Contains a Enzyme hirudin which prevents blood
clotting
(6) PHYLUM MOLLUSCA (SOFT BODIED ANIMAL)
* Second largest phylum
* Largest invertebrate – Gram squlds
* External hard covering calcium carbonate shell
* A grinding structure radula is present in the
buccal cavity
* Thin membraneous covering of the body – mantle
* Respiration through gills
* Locomotary organ a mascular foot
* Larva – Trocophore larva
CLASS GASTROPODA
A phenomenon torsion is present in which the
animal body rotates at the angle of 180˚
Example: Pila
CLASS BIVALVIA
* Second largest class of mollusca
* Shell consist of two parts and attached with
eachother by hinge joint
* Common examples: Unio, mytilus and pearl
oysters
CLASS CEPHALOPODA
* All members are marine
* Locomotary organ foot transformed into suckers
which bears tentacles and arms
* Example: Sepia (cuttle fish), loligo (squids),
octopus (devil fish)
* Shell is absent in octopus
(7) PHYLUM ARTHROPODA ( JOINTED LEGS)
* Largest phylum
* One million species
* Metamerically segmented animals
* Blood filled cavity hoemocoel is present
* Blood without haemoglobin (white)
* Respiration: Gills, Trachea or Book lungs
* Excretory organs malphigian tubules
* Nervous system well developed
* Compound erges with sharp vision
* Metamorphosis = developmental changes which
transforms a larva into its developed adult form
* Incomplete metamorphosis = egg → nymph → adult e.g.
cockroach
* Complete metamorphosis = ® egg ® larva ® pupa
® adult e.g. Butterfly, common, housefly and mosquito
* Moulting (ecdysis)
* Changing over of old exoskeleton and formation
of a new one
* Apiculture => Farming of honey bees
* Sericulture => Farming of silk worms
CLASS MEROSTOMATA
Limulus (king crab)
CLASS ARCHINIDA (SPIDER LIKE)
* Group of Spiders & Scorpions
* Respiration through book lungs
* Four pair of walking legs
CLASS CRUSTACEA
* Class of prawns, shrimps, lobsters, crabs
* Two pairs of antenae, one pair of mandible and
two pair of maxilla
* Exoskeleton a large plate of carapase
* Sacculina is the only parasitic member
CLASS MYRIAPODA
* Class of millipedes and centipedes
* Body is divided into similar multiple segments
CLASS INSECTA OR HEXAPODA
* Largest class (eight lakhs & 50,000 members)
* Study of insects is called entomology
* Three pairs of walking legs
* Pterygota (insects with wings)
* Apterygota (insects without wings)
* Social insects: Ants, termites, honey bees
(8) PHYLUM ECHINODERMATA (ANIMAL WITH SPINY
SKIN)
* Marine animals
* Radially symmetrical
* Pentamerous body
* Water vascular system is present
* Locomotary organs are tube feets = External
openings of the water vascular system
* Exoskeleton is made up of calcarious plates in
the form of spines
* Power of regemeration is very great
* Phylum echinodermata, hemichordata &
chordate posses common ancestor
* Bipinnaria larva is present
* Common e.g. Sea Star (Star fish, Brittle star,
Sea dollar, Sea urchins, Sea cucumbers.
(9) PHYLUM HEMICHORDATA (ANIMAL WITH HALF
NOTOCHORD)
* Notochord in future = Vertebral column + Skull
* Dorsal nerve cord = Brain and Spinal cord
* Pharengeal gill slits <-->Aquatic
animals = gills
* -> Terrestrial = Internal neck structures
* Only 90 species are present
* Larva is tornaria larva
* Open circulatory system
(10) PHYLUM CHORDATA
GROUP ACRANIATA
Brain without any covering or skull
SUB-PHYLUM UROCHORDATA
* Also known as tunicates
* Body is enclosed in a sac tunic
* Only embryonical stages show chordate
characters
SUB-PHYLUM CEPHALO CHORDATA
Embryonic as well as adult both forms show
typical chordate characters
GROUP CRANIATA OR VERTEBRATA
Brain and spinal cord is enclosed in a hard
covering skull & vertebral column respectively
SUB-PHYLUM AGNATHA (ANIMALS WITHOUT JAWS)
* Also known as cyclostomes or jawless fishes
* Totally parasitic
* Teeth are present in the form of rings
* Common e.g. Hag fishes, lamprey
SUB–PHYLUM GNATHOSTOMATA (ANIMAL WITH JAWS)
* Teeth may be present or absent
* Amphibians and bird lack teeth
* Fishes, reptiles, mammals do have teeth
1. SUPER - CLASS PICSES (FISHES)
Study of fish is known as echthylogy
SUB – CLASS CHONDRICHTHYES (CARTILAGENOUS
FISHES)
* Endo skeleton is cartilaginous (soft boned)
* Exoskeleton – Placoid scales
* Fins are heterocircle (different size and
shaped)
* Gills without any covering
* Common example (Sharks, Squids, torpedo,
electric ray)
* Scolidoen (dog fish) – Small Shark
SUB - CLASS OSTEOCHYTHES (BONY FISHES)
* Exoskeleton cycloid or ctenoid scales
* Operculum is present (covering of gills)
* Fins are homocircle (Same size and shape)
* Lung fishes are included in order dipnoi.
2. SUPER CLASS TETRAPODA
1. CLASS AMPHIBIA
* Exoskeleton is absent
* Respiration by lungs, gills or skin
* Fertilization is external
* Cold blooded
* Having the characteristics of hibernation
& aestivation
* Common e.g. Toads, frogs, salamanders etc.
2. CLASS REPTILIA
* Included in group amniota due to the presence
of amnion in eggs
* Fertilization is internal
* Exoskeleton is made up of thick horny scales
* Important members are snakes, turtles,
lizards, crocodiles and alligators
* Venom → Snake poison
* Fangs → sharped and curved teeth of snake
3. CLASS AVES (BIRDS)
* Study of birds is called ornithology
* They posses hollow bones (Pneumatic bones)
* Sound producing organ “Syrinx” is present
instead of larynx.
* Teeth totally absent.
SUB CLASS RETITA (FLIGHT LESS BIRDS)
* E.g. Penguin, Kiwi, Ostrich.
* Ostrich → Largest Bird.
SUB CLASS CARNIATAE (FLYING BIRDS)
* Wings with interlocking system.
* Common e.g. Peacock, Seagulls, Kites, Falcon
etc.
* Archeopetryx → Intermediate specie between
reptiles and birds.
4. CLASS MAMMALIA
* Presence of mammary glands and hairs.
* A muscular organ diaphragm, which separates
thoracic cavity from abdominal cavity.
* Teeth are present with different size and
shape (heterodont).
a- Incissors → for biting and cutting purpose
b- Canives → Tearing purpose
c- Pre-Molars -> For grinding and holding
purpose
d- Molars -> For grinding and holding purpose
SUB CLASS PROTOTHERA (EGG LAYING MAMMALS)
* Also called monotremous.
* Two genera with 3 species
* Oviparous.
* Common urogenital opening Cloaca is present.
* External ear is absent.
* It is a connecting link between reptiles and
true mammals. e.g. spiny anteater, duck billed platypus.
SUB CLASS METATHERIA (POUCHED MAMMALS)
* Marsupials
* Give birth to live young ones.
* Special pouch like bag is present in the
ventral side of female.
* This pouch is known as marsupial.
* Common e.g. Kangaroo, Kuala bear, Opossums.
SUB CLASS EUTHERIA (PLACENTAL ANIMALS)
* 95% of mammals are included in this group.
* Viviparous.
* Placenta → connecting link between mother and fetus.
* Common e.g. Camel, donkey, elephant, bat,
whale, dolphin.
* Markhor is the national animal of Pakistan
also known as Wild goat
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Phylum Chordata
Friendsmania.net
* It includes animals, which exhibit great
difference of anatomy, physiology and habits.
* These animals are highly developed.
INDEX
* 1 GENERAL CHARACTERS
* 2 1. NOTOCHORD
* 3 2. DORSAL HOLLOW NERVOUS SYSTEM
* 4 3. GILL CLEFTS
* 5 4. PHA-RYNGEAL POUCHES
* 6 OTHER FEATURES
* 7 CLASSIFICATION OF PHYLUM CHORDATA
* 8 1. GROUP ACRANIATA (PROTOCHORDATA)
* 9 A) SUB-PHYLUM UROCHORDATA (NOTOCHORD IN
TAIL)
* 10 B) SUB-PHYLUM CEPHALOCHORDATA (NOTOCHORD
FROM HEAD TO TAIL)
* 11 2. GROUP CRANIATA (VERTEBRATA)
* 12 A) SUB-PHYLUM AGNATHA (MOUTH WITHOUT JAWS)
* 13 B) SUB-PHYLUM GNATHOSTOMATA (MOUTH WITH
JAWS)
* 14 I) SUPER CLASS PISCES (FISHES)
* 15 LUNG FISHES
* 16 II) SUPER CLASS TETRAPODA
* 17 A) CLASS AMPHIBIA
* 18 B) CLASS REPTILIA
* 19 C) CLASS AVES (BIRDS)
* 20 CHARACTERS OF CLASS AVES
* 21 SUB-CLASSES OF AVES
* 22 D) CLASS MAMMALIA
* 23 CLASSIFICATION OF CLASS MAMMALIA
GENERAL CHARACTERS
The chordate animals at some time in their life
history exhibit the following diagnostic characters:
1. NOTOCHORD
* It is an elastic, solid, skeletal rod lying
below the nerve cord and above the alimentary canal.
* It serves as a primitive internal skeleton and
acts as a rigid axis.
* It may persist throughout life or it may be
replaced partially or completely by a backbone or vertebral column.
2. DORSAL HOLLOW NERVOUS SYSTEM
* There is a dorsal, hollow, fluid filled nerve
cord.
* It is formed by enfolding of a mid-dorsal
strip of ectoderm and it generally sinks below the surface.
* It lies above the notochord and outside the
coelom.
* It persists throughout life in most chordates,
but in a few it degenerates before maturity.
3. GILL CLEFTS
* These are paired openings leading from the
Pharynx to the exterior.
* Such gill clefts appear during the development
of every chordate, but in many aquatic forms they are lined with vascular
lemallae, which forms gills for respiration.
* In terrestrial chordates, which never breath
by gills, gill clefts are present during early development but later on, they
disappear.
4. PHA-RYNGEAL POUCHES
* All the chordates have paired pharyngeal
pouches at some stage of their life cycle.
* These extend from laterally from the anterior
part of the digestive tract towards the body wall.
OTHER FEATURES
* Chordates are triploblastic.
* They are bilaterally symmetrical.
* True coelom is found.
* They are found in almost all the habitats of
the World.
CLASSIFICATION OF PHYLUM CHORDATA
The Phylum Chordata is divided into two groups
which are:
1. Acraniata (Protochordata)
2. Craniata (Vertebrata)
1. GROUP ACRANIATA (PROTOCHORDATA)
* They are first or simple Chordates.
* Brain box (Cranium) is absent and hence brain
is not prominent.
* Notochord does not transform into vertebral
column.
This group is further divided into two
sub-phyla, which are as follows:
a) Sub-Phylum Urochordata (Notochord in tail)
b) Sub-Phylum Cephalochordata (Notochord head to
tail)
A) SUB-PHYLUM UROCHORDATA (NOTOCHORD IN TAIL)
* They are also known as “Tunicates” because
their body is enclosed in a sac called “Tunic.”
* All members are marine and sessile.
* Body possesses two openings, an incurrent or
buccal siphon and an excurrent or Atrial siphon, through these openings
exchange of gases and food or waste material take place.
* As a result of “Retrogressive metamorphosis”
the larva loses its tail and most of chordate characters and converts into an
adult.
* E.g: Ascidia, Herdmania etc.
B) SUB-PHYLUM CEPHALOCHORDATA (NOTOCHORD FROM
HEAD TO TAIL)
* This is a small group of marine animals, body
with pointed ends.
* Usually live buried in sand, in shallow water
with anterior end protruded out.
* They show all typical chordate characters
(hollow dorsal nerve chord, pharyngeal gill slits and notochord).
* Only two genera are present around the world.
* E.g: Branchiostoma (Amphioxus) etc
2. GROUP CRANIATA (VERTEBRATA)
* In these chordates brain is protected inside a
skeletal brain box called “CRANIUM.”
* Also known as “Vertebrates” because notochord
is replaced by a vertebral column.
This group is sub-divided into two sub-phyla,
which are as follows:
a) Sub-Phylum Agnatha (Mouth without Jaws)
b) Sub-Phylum Gnathostomata (Mouth with Jaws)
A) SUB-PHYLUM AGNATHA (MOUTH WITHOUT JAWS)
* This is a small group of marine vertebrates
also known as “Cyclostomes.”
* Superficially they resemble the fish but lack
the jaw so they are often known as “Jawless Fishes.”
* They have rounded suctorial mouth with many
rings of teeth.
* Paired fins and scales on body.
* Usually parasitic in nature.
* E.g: Hag Fish, Lamprey etc.
B) SUB-PHYLUM GNATHOSTOMATA (MOUTH WITH JAWS)
* It is a large group of vertebrates with both
upper and lower jaw.
* Teeth may be present or absent.
Gnathostomata are divided into two super
classes, which are as follows:
i) Pisces (Fishes)
ii) Tetrapoda
I) SUPER CLASS PISCES (FISHES)
* This is the largest group of chordates, which
includes half of the chordate (25,000 species).
* Study of fishes is called “Ichthyology.”
* Body is streamlined with paired fins and
covered over by dermal scales.
Super class Pisces is divided into two classes,
which are:
i-a) Chondrichthyes (Cartilage Fishes)
i-b) Osteiochthyes (Bony Fishes)
I-A) CLASS CHONDRICHTHYES (CARTILAGE FISHES)
* Alternate name is “Class Elasmobranchi.”
* Usually includes marine fishes with
endoskeleton of cartilage (soft bone).
* Skin contains sharp tiny enamel coated
denticles called “Placoid Scales,” which form exoskeleton.
* · Mouth is ventral in position and tail fin is
“Heterocercal.”
* Five exposed gill slits, which are not covered
over by a gill cover.
* Common examples are Skates, Sharks, Rays and
Scoliodon (Dog Fish)- a small Shark etc.
I-B) CLASS OSTEIOCHTHYES (BONY FISHES)
* Alternate name is “Teleostom,” actually the
largest class of chordates.
* Includes marine and fresh water fishes.
* Mouth is present at anterior tip.
* Endoskeleton in these fishes is made up of
hard bone while exoskeleton is made up of thin bony plates, which are known as
“Cycloid” or “Ctenoid scales.”
* Gills are covered over on each side by a gill
cover called “Operculum.”
* An air bladder is present which acts as a
hydrostatic organ.
* Tail fin is usually “Homocercal or
Diphycercal.”
* Common e.g are Eel, Sea-Horse, Flying Fish,
Globe Fish etc
LUNG FISHES
* Zoogeographically important fishes, belonging
to group “Dipnoi, included in Class Osteiochthyes.
* Only three living genera.
* They respire by gills and by lungs during
drought period (Lungs-Modified air bladder).
* Limited distribution in South America, Africa
and Australia.
* E.g: Protopterus (African Lung Fish)
II) SUPER CLASS TETRAPODA
* It includes following classes:
a) Class Amphibia
b) Class Reptilia
c) Class Aves
d) Class Mammalia
A) CLASS AMPHIBIA
* This class includes the animals that came out
of the water and established a successful life on land.
* They took advantages of the improved
possibilities by remaining close to water, by keeping a soft and moist skin, by
developing lungs and by evolving a bony skeleton with a strong vertebral column
and four legs.
* They cope with seasonal changes by burrowing
during extreme cold and save water by sealing themselves in a mucous envelop on
dry land.
* The bony endoskeleton is the main body
support.
* The notochord is absorbed during development
* Breathing is mostly by means of skin and also
lung, and also by lining of buccal cavity.
* In larva the breathing is mostly by means of
external or internal gills.
* The circulatory system shows a three chambered
heart, with two atria and one ventricle.
* The amphibians are “Cold Blooded”
(Poikilothermic) that is having internal temperature that very with the
environment.
* Eggs and sperms are laid in water and fertilization
is external.
* E.g: Frog and Toads, Salamanders, Newts, Mud
puppies etc.
B) CLASS REPTILIA
GENERAL CHARCTERS
The earliest reptiles evolved from the
amphibians.
HABIT AND HABITAT
Reptiles are generally well adapted to life on
land, in semi-dry, completely dry and even desert habitat.
NATURE
* All reptiles lay their eggs on land.
* They are cold-blooded animals and are less
active during low temperature.
STRUCTURAL FEATURES
* They possess dry skin covered with epidermal
scales.
* In some lizards and crocodiles, small bony
plates develop below the epidermal scales.
* The skeleton is built on the same plane as
that of amphibians, but is much stronger to support their body weight.
* Respiration takes place exclusively through
lungs.
* Heart is three chambered, two auricles and one
incompletely divided ventricle. (In Crocodiles, the ventricle is completely
divided into two chambers.)
* The excretion takes place through kidneys. The
reptiles secrete much of their waste products in form of non-toxic “Uric-Acid.”
REPRODUCTION
* In most reptiles fertilization is internal.
* Eggs are provided with a shell and are laid on
land.
* The early development of embryo takes place on
the large quantities of yolk and albumin present in the egg.
* Due to the presence of a protective membrane
called “AMNION” in the egg, reptiles are included in the “Amniota Group” of
Vertebrates.
EXAMPLE
Alligators, Crocodile, Snake, Turtle and Gecko
etc.
C) CLASS AVES (BIRDS)
EVOLUTION
* Aves have evolved from reptiles.
* As they acquired the capability of true flight
they were able to exploit the aerial environment and became the largest class
of terrestrial vertebrates.
CHARACTERS OF CLASS AVES
HABIT AND HABITAT
The birds live from pole to pole in all type of
ecological zones. They all breed on land.
FLIGHT AND ADAPTATION
* Feathers differentiate birds from all other
vertebrates.
* Feathers originated as extraordinary
development of Reptilian scales.
* Instead of growing all over the body and
spreading evenly, the feathers grow in definite tracts.
* The feathers play an important role in the
thermoregulation of birds. They trap air, which is a bad conductor of heat and
so prevent loss of body heat.
* To fly efficiently the birds have reduced
their body weight in a variety of ways.
* Many bones become hollow, thin and light.
* Synsacrum and pygostyle are formed by the
fusion of vertebrae and give strength to skeleton.
* Birds possess strong muscles to control the
use of wing in flight.
ADAPTATION FOR COMMUNICATION
* They possess large eyes with well-developed
sight.
* The birds communicate with members of their
species with sound signals for which the sense of hearing is well developed.
STRUCTURAL FEATURES
* The great mobility of neck is helpful in
feeding, nest building, preening and defence.
* There are developed a number of types of bills
according to their feeding habits.
* The digestive system of birds is compact and
can accommodate large quantity of food.
* The food is stored for a short period in the
crop.
* “Gizzard” possess thick muscular wall with
horny lining, small stones swallowed by birds are passed on the gizzard for
grinding the food.
* The “Syrinx” or sound-producing organ is found
in no other vertebrate except the birds. It is located at the junction between
the trachea and the paired bronchi.
* The lungs of birds are small, solid, spongy
and slightly distensible. They are in contact with a number of air sacs.
MIGRATION IN BIRDS
A large number of species of birds exhibit a
deep-rooted phenomenon of migration, during which they travel long distances
from their summer breeding homes towards areas of warm climate.
SUB-CLASSES OF AVES
There are two main sub-classes of aves, which
are:
i) Sub-Class Ratitae (Flightless Birds)
ii) Sub-Class Carinatae (Free-Flying Birds)
I) SUB CLASS RATITAE (FLIGHTLESS BIRDS)
* This sub-class includes modern big sized
flight less birds.
* They comparatively have heavy weight and their
wings are either vestigial or rudimentary.
* They have a flat sternum without keel.
* Their flight muscles are poorly developed.
* The distribution of these birds is restricted
to few areas of the World.
* E.g: Ostrich, Rhea, Emu, Cassowary, Kiwi and
Penguin.
II) SUB-CLASS CARINATAE (FREE FLYING BIRDS)
* In this sub-class modern flying birds are
included.
* They are usually small, light weight birds
with highly developed wings and feathers with interlocking system.
* They possess sternum with a crest like keel to
accommodate the hightly developed pectoral flight muscles.
* The flying birds are distributed all around
the World.
* E.g: Sparrow, Pigeons, Myna, Bulbul, Hoopoes,
Crow, Doves, Parrots, Fowls, Cuckoo and Ducks etc.
D) CLASS MAMMALIA
Early mammals are originated from reptiles. The
distinctive characteristic of mammals are at the highest grade of development
in animal kingdom.
GENERAL CHARACTERS
HABIT AND HABITAT
Mostly terrestrial, a few aquatic.
NATURE
* They are warm-blooded animals.
* They can maintain a fairly high body
temperature and so can successfully survive in colder areas of the world.
TEMPERATURE REGULATION
* Heat is generated by high metabolic rate of
their body and is lost by increasing blood circulation in the skin and evaporation
of sweat.
* The mammalian body temperature is maintained
at 35˚C-40˚C.
APPARENT FEATURE
* All mammals possess hair on skin.
* Sweat glands and sebaccous glands are present
on skin.
* Mammary glands secrete milk in females.
* External ears (Pinna) are present.
* Teeth are heterodont i.e. not uniform. The
different types of teeth are: Incisors, Canine, Premolars, Molars.
SKELETAL SYSTEM
* Skull with two occipital condyles is present.
* Lower jaw is composed of single bone on each
side.
* Vertebrae are “Gastrocentrous,” composed of
three pieces i.e. the centrum and two epiphyses.
* Digits of fore and hind limbs are usually
five.
* Cervical (Neck) vertebrae are seven.
INTERNAL FEATURES
* A thick muscular septum “Diaphram” is present
between abdomen and thoracic cavity.
* Heart is four-chambered.
* R.B.Cs are non-nucleated.
* Brain with four optic lobes.
* Kidney is metanephrous.
* The stomach is simple sac but rarely
complicated.
REPRODUCTION
* Mammals give birth to young ones (Viviparous),
which are nourished by parents. Except Prototherians that lay eggs.
* Fertilization is internal.
* Development of eggs occurs in the uterus of
female, where the developing embryo develops relationship with mother (Placenta).
* After the birth of the child, the mother
nourished her young ones.
CLASSIFICATION OF CLASS MAMMALIA
Mammals are divided into three sub-class:
1. SUB-CLASS PROTOTHERIA
Includes the egg laying mammals. For example
Duck billed, Echidna (Spiny anteater).
2. SUB-CLASS METATHERIA
Includes the pouched mammals, also known as
“Marsupial mammals.” For example Kangaroo, Koala Bear and Opossums etc.
3. SUB-CLASS EUTHERIA
Includes the placental mammals. For example
Monkey, Cow, Elephant, Cat, Dog, Bat, Whale and Human being etc.
Kingdom Anamalia
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Classification of Kingdom Anamalia
* The classification or grouping of animals is
called Taxonomy or Systematics, primarily on the basis of their evolutionary
relationships.
* Major phyla of kingdom Animalia are as follows
* Phylum Porifera (Sponges)
* Phylum Cnidaria (Coelenterata)
* Phylum Platyhelminthes (Flat worms)
* Phylum Aschelminthes (Nematoda/Round worm)
* Phylum Annelida (Segmented worms)
* Phylum Mollusca (Shelled Animals)
* Phylum Arthropoda (Jointed Appendages Animals)
* Phylum Echinodermata
* Phylum Hemichordata
* Phylum Chordata
* Summary of Kingdom Anamalia
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Phylum Porifera (Sponges)
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Word Porifera is derived from Latin Porus –
Pores and Ferro – to bear. The animals are also called “Sponges”.
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Phylum Cnidaria (Coelenterata)
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This phylum include such simple animals having
only two body layers. Hence these are called DIPLOBLASTIC
MAIN CHARACTERS
HABIT AND HABITAT
They are aquatic animals, mostly marine and few
fresh water forms. They are sedentary or free swimming and solitary or colonial
STRUCTURE
* The cnidaria are metazoa having the simplest
type of body wall consisting of two layers. The outer epidermis and the inner
gastrodermis which lines the body cavity.
* In between the two layers lies the mesogloa,
non-cellular jelly secreted by them.
* Cnidarians, due to their two layers body wall
are termed as diploblastic animals. All other metazons possesses a third layer
called mesoderm in their body wall, laying in between the epidermis and
gastrodermis (Endoderm) and are therefore called Triploblastic animals.
* They have radially symmetrical body plan
organized as a hollow sac.
* The mouth is surrounded by a circle of
tentacles bearing cnidoblasts stinging cells containing nematocysts.
* They have central digestive cavity connected
to the outside by mouth.
STRUCTURAL TYPES
The Cnidarians are radially symmetrical and
occur in two types of forms.
(a) The polyp
(b) The Medusa
(A) POLYP
The polyp like Cnidarian for example sea anemone
has a cylindrical body with a mouth directed upwards and surrounded by
tentacles. The basal surface of the body is attached to the substratum.
(B) MEDUSA
The medusa like Cnidarians jelly fish are
umbrella like in appearance. Their oral surface, bearing the mouth is directed
downwards. Whereas the aboral surface is directed upward. The medusoid
Cnidarians are usually free swimming.
PROCESS OF FEEDING AND DEFENCE
* The Cnidarians feed mostly on animal diet.
* The food is digested in the gut and the waste
products are expelled through the mouth.
* The Cnidarians so named, because they possess
cnidoblasts bearing nematocysts which help in feeding and defence.
REPRODUCTION
The Cnidarians reproduce by asexual as well as
sexual methods. Polypoid Cnidarians possess a remarkable ability to regenerate.
(A) REGENERATION
If the oral part of the body is lost. The
remaining part regenerates the new mouth and the whole of tentacles.
(B) ASEXUAL REPRODUCTION
A sexual reproduction takes place by Budding.
(C) SEXUAL REPRODUCTION
* The sexual reproduction takes place through
male or female gametes which are usually produced by different parents.
* The gametes develop in the interstitial cells
and aggregate in gonads which are located either in the epidermis or in the
gastodermis.
* The fertilized egg gives rise to “Planula
Larva”
CLASSIFICATION OF CNIDARIA (COELENTERATA)
The Phylum Cnidaria is divided into three
classes:
1. Hydrozoa
2. Scyphozoa
3. Anthozoa
1. HYDROZOA
As the most primitive class of the Cnidarians,
Hydrozoa is thought by some evolutionists to have given rise to both other
classes. They show following characteristic features:
* They are mainly marine, but some are fresh
water species
* Many species have both polyp and medusa
For e.g:
Hydra, Obelia and Physalia
2. SCYPHOZOA
* Most of animals of this class are commonly
called “Jelly Fish”.
* They are semitransparent and are of various
colours.
* Most are of marine habitat.
For e.g:
Aurelia and Cyanea (largest Jelly Fish)
3. ANTHOZOA
* These animals are mostly marine.
* Solitary or colonial Polyp forms are present.
* Medusa stage is absent.
* Gastrovascular cavity is divided into
chambers, increase area for digestion.
For e.g:
Sea-anemones and Corals etc
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Phylum Platyhelminthes (Flat worms)
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The term Platyhelminthes is derived from Greek
Platy – flat and Helmenthes – worms. This Phylum include Flat worms.
INDEX
* 1 MAIN CHARACTERS
* 2 HABIT AND HABITAT
* 3 NATURE
* 4 EXTERNAL FEATURES
* 5 INTERNAL FEATURES
* 6 REPRODUCTION
* 7 EXAMPLES
MAIN CHARACTERS
HABIT AND HABITAT
Animals are mostly Parasitic in habitat and
found in other higher animals. But some animals are also free living.
NATURE
They are triploblastic in nature i.e. body is
composed of three germinal layers, viz, ectoderm, mesoderm and endoderm
EXTERNAL FEATURES
* Their bodies are compressed dorsoventrally and
shows bilateral symmetry.
* Body shape generally worm like but vary from
moderately elongated flattened to long flat ribbons and leaf like.
* The flat worms are small to moderate in size
varying from microscopic to as long as up to 10-15 m.
* Majority of animals are white or colourless,
some derive colour from ingested food.
* Anterior end of body is differentiated into
head.
* Ventral surface bearing mouth and genital
pores.
* Presence of great variety of adhesive parts
e.g. suckers.
* Body is covered by cuticle or by ciliated
epidermis.
* Hard part consist of cuticle, spines, thorns
or hooks etc.
INTERNAL FEATURES
* Endo and Exo skeleton are completely absent,
hence the body is generally soft.
* Acoelomate i.e. true coelom is absent.
* Body space between various organs is filled
with MESENCHYME.
* Digestive system is poorly developed or
absent.
* Respiratory and Circulatory systems are
absent.
* Excretory system consists of Protonephridia or
flame cells.
* Nervous system is primitive. The main nervous
system consists of a pair of cerebral ganglia or brain and 1-3 pairs of
longitudinal nerve cords, connected to each other by transverse commissures.
REPRODUCTION
* Platyhelmenthes are hermaphrodite i.e. male
and female sex organs are present in same individual.
* In majority of forms eggs are devoid of Yolk
but provided with special yolk cells.
* Cross fertilization as well as self
fertilization is present.
* Life cycle may be simple or complicated
involved one or more hosts.
EXAMPLES
Planaria, Liver flukes, Schistosoma and Taenia
Solium etc
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Aschelminthes (Nematoda/Round worm)
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Nematoda are called Pin worm or round worms.
INDEX
* 1 MAIN CHARACTERS
* 2 HABIT AND HABITAT
* 3 NATURE
* 4 EXTERNAL FEATURES
* 5 INTERNAL FEATURES
* 6 REPRODUCTION
* 7 EXAMPLES
MAIN CHARACTERS
HABIT AND HABITAT
* Nematoda have a very wide distribution and
they seem to have mastered almost every habitat.
* Free living nematodes are found in the sea,
fresh water or in the soil in all kinds of environment.
* There are also many Parasitic nematodes found
in all groups of Plants and animals.
* The Saprophagous species live in decomposing
plant and animal bodies and in rotting fruits.
NATURE
They have a bilaterally symmetrical, cylindrical
body, glistening smooth surface. They are triploblastic.
EXTERNAL FEATURES
* They show no trace of segmentation.
* Most of the free living nematodes are less
then a millimeter length.
* Some of the parasitic species attain a length
of several meters e.g. Guinea worm (Dracunculus medinensis).
* They are usually long, round, tapered at both
ends showing very little morphological diversity from species to species.
* The mouth of nematodes is modified for various
modes of feeding such as cutting, tearing, piercing and sucking fluids from the
host.
* Body is covered by cuticle, which moults only
during the period of growth.
INTERNAL FEATURES
* The organs are packed in parenchyma when
young, but later on it disappears in adult. So that organs lie in a fluid
filled cavity. This cavity is termed as PSEUDOCOEL and it has not peritoneum.
* Muscles are only longitudinal.
* Excretory system has no flame cells.
* Alimentary canal is straight with ectodermal
fore and hind gut and an endodermal mid gut.
REPRODUCTION
* Sexes are generally separate.
* Gonades are tubular and continues with their
ducts.
* Female organs are usually paired and open by
vulva.
* Male organs are single and open into a cloaca.
* The life cycle of Parasitic species involves
one, two or more hosts
EXAMPLES
Ascaris (Round worms), Hookworms and Thread
worms etc.
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Phylum Annelida (Segmented worms)
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The word Annelida is derived from latin Annelus
meaning little ring.
MAIN CHARACTERS
NATURE
Annelida are triploblastic, symmetrical,
coelomata and segmented metozoa.
HABIT AND HABITAT
Annelida are mostly aquatic, marine or fresh
water, burrowing or living in tubes, some free living forms.
EXTERNAL FEATURES
* The most important feature of annelida is
their metameric segmentation. (External segmentation)
* Segmentation is indicated externally by
circular constrictions or grooves on the body wall.
* Outer covering of the body is cuticle secreted
by the underlying epidermis.
* Appendages, when present are unjointed.
* Locomotory organs are segmentally arranged,
paired setae or chaetae.
INTERNAL FEATURES
* Body wall is contractile, consists of an outer
epidermis, circular and longitudinal muscles.
* The gut, longitudinal blood vessels and the
nerve cord extend throughout the body length, whereas other structures are
repeated in each segment.
* Important character of annelida is the
development of series of coelomic compartments in their body between the gut
and the body wall.
* The Coelom is a cavity, which develop within
the mesoderm and is lined by mesodermal cells.
* Segmented musculature plays an important part
in locomotion of Annelids.
SYSTEMS OF BODY
* Alimentary canal is tube like extending
straight from mouth to anus.
* Respiration through general body surface, by
gills in some forms.
* Blood vascular system is closed type.
* Blood is red due to haemoglobin.
* Excretory organs are Nephridia usually one
pair in each segment.
* Nervous system consists of dorsal brain and
longitudinal ventral nerve cord.
* Sexes may be united or separate.
* Development is direct when sexes are united
and indirect when sexes are separate.
EXAMPLES
Nereis, Earthworm and Leeches etc.
CLASSIFICATION OF PHYLUM ANNELIDA
Phylum Annelida is divided into four classes:
1. Polychaeta
2. Oligochaeta
3. Hirudinea
4. Archiannelida
1.POLYCHAETA
LOCOMOTORY ORGANS
The Polychaetes possess paired parapodia
functioning as locomotry appendages, are present only in the class Polychaeta.
PROSTOMIUM
Usually there is a distinct head or Prostomium
bearing sensory and feeding appendages.
MODE OF LIFE
The Polychaetes may be carnivorous, scavengers,
or filter feeders.
REPRODUCTION
The sexes are separate and fertilization of eggs
takes place outside body. Their free swimming larva is called Trochophore.
RESPIRATION
The respiration takes place through the body
surface in many but in some gills may be present as respiratory organs.
EXAMPLES
Some well-known examples of marine polychaetes
are Nereis, Arenicola and Sabella. Nereis lives beneath stones and in crakes of
rocks.
2.CLASS OLIGOCHAETA
LOCOMOTORY ORGANS
The Oligochaetes possess fewer numbers of Setae
as compared to the Polychaetes. The setae help the earth worms in crawling.
SENSE ORGANS
There anterior end lacks eyes, or sensory
appendages.
CLITELLUM
At sexual maturity, all of the oligochaetes
develop in several segment, glandular epithelium, called clitellum.
MODE OF LIFE
* Oligochaetes live either in fresh water or on
land.
* There is no free swimming larval stage in
their development
* Majority of oligochaetes are scavengers,
feeding on decomposing organic matter.
* Some fresh water species feed on algae.
* Burrowers like earth worm ingest a large
quantity of soil, digest the organic matter and the living fauna.
RESPIRATION
Respiration takes place through their general
body surface. Some aquatic species possess anal gills.
ECONOMIC IMPORTANCE
Earthworms increase the fertility of soil by
physically over turning it. They ingest the soil, break it down and deposit it
in the form of casts. The over turned soil is relatively in proportions of
total nitrogen, organic carbon, calcium, magnesium and phosphorus.
3.CLASS HIRUDINEA
BODY SEGMENTS
Unlike polychaetes and oligochaetes, the number
of body segment in leeches is fixed at 34.
SUCKERS
The anterior and posterior body segments are
fused to form suckers.
LOCOMOTION
Leeches either swim or crawl.
RESPIRATION
Respiration generally takes place through the
body surface. Leaf like gills may be present.
PARASITIC NATURE
Most leeches feed by sucking blood of aquatic
invertebrates and vertebrates.
4.ARCHIANNELIDA
* It is a small group of marine worms.
* They are not segmented externally and don’t
have bristles.
* They live in the sea and show annelid
characteristics to a minor extent.
* Their development is also characterized by
Trochophore Larva.
EXAMPLES
* Nerilla
* Dinophilus
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Phylum Mollusca (Shelled Animals)
Mollusca is the second largest phylum of the
animal kingdom, and include Slugs, Clams, Scallops and Squids.
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MAIN CHARACTERS
HABIT AND HABITAT
The majority of molluscs are marine. Some snails
and clams inhabit fresh water while slugs are terrestrial.
NATURE
* Molluscs are primitively bilaterally
symmetrical animals.
* Some molluscs serve as intermediate host of
helminthes parasites and some are destructive to wooden bottom of ship.
EXTERNAL FEATURES
* The body is soft, unsegmented and consists of
head, foot, mantle and visceral mass.
* The body is clothed with a one layered
epidermis.
* Body is commonly protected by an exoskeletal
calcerous shell of one or more pieces, secreted by Mantle.
* Head is distinct, bearing the mouth and
provided with eyes, tentacles and other sense organs.
INTERNAL FEATURES
* Visceral mass contains the organs of the body
in compact form.
* Body cavity is hoemocoel.
* Digestive system-tract is simple.
* Circulatory system is open.
* The mouth in many species possesses a radulla,
(a tongue like structure) that can be protruded to scrape, tear or pull food.
* The respiration is by means of gills or lungs.
* The nervous system consists of cerebral ganglion,
a pair of pedal cords to the foot and a pair of visceral mass.
REPRODUCTION
* Molluscs may have separate sexes or they may
be hermaphrodite.
* The fertilized eggs give rise to a larva stage
which transform into adult.
* Three types of larva trochophore, veliger and
glochidium occur in molluscs.
CLASSIFICATION OF MOLLUSCA
The phylum Mollusca is divided into six classes:
1. Amphineura
2. Scaphopoda
3. Gastropoda
4. Bivalvia
5. Cephalopoda
6. Monoplacophora
CLASS GASTROPODA
EXAMPLE
This is the largest class of mollusca which
included Snails, Whelks, Conchs, Limpets, Cowries and Slugs.
CHARACTERS
* The gastropods are mostly marine, though some
live in fresh water and a few are terrestrial.
* The gastropods are asymmetrical.
* They have a well developed head and a broad
muscular foot.
* Both are on the ventral side of their body.
* Their visceral organs are located on the
dorsal side and are enclosed in a one piece shell which is spirally coiled.
* The gastropods use the redula to scarp food
particles or to drill holes in the shells of bivalves.
* Some are carnivorous, a few are filter
feeders.
CLASS BIVALVIA
* The class Bivalvia is the second largest class
of the Phylum Mollusca.
* The bivalves are bilaterally symmetrical with
a laterally compressed body enclosed in a shell of two pieces (valves) hinged
together.
* The shell can be opened or closed.
* By closing the shell tightly, the animals can
protect it self off from unfavourable environment or saves itself from
predators.
* The head is rudimentary and the radula is
absent.
* The foot is ventral, laterally compressed,
usually wedge shaped.
EXAMPLE
Bivalves include the Clams, Mussels, Oysters and
Scallops. They are mostly marine some live in fresh water but none is
terrestrial.
PEARL FORMATION
* When a foreign particle living or dead enters
a bivalve it causes irritation.
* The epithelial cells of the mantle start
depositing concentric layers of calcerous material around it, which ultimately
forms a pearl.
* Pearl culture has been successfully carried
out by artificially introducing fragments of man made hard material in pearl
oysters.
* Pearls are formed both in marine as well as
fresh water species.
CLASS CEPHALOPODA
* The cephalopods are all marine and exhibit a
high level of development.
* Nautilus is the only living cephaloped that
possesses a well developed external shell which is coiled and divided by
transverse Septa in chambers.
* The shell is reduced and overgrown by mantle
in Squids and Cuttle fish.
* It is completely absent in Octopus.
EXAMPLES
Nautrilords, Squids, Cuttle fish, Octopus etc.
CLASS MONOPLACOPHORA
* They are primitive molluscs with a long fossil
record.
* They have only one living representative,
Neoporlina, which retains the segmented characteristics of annelids, lost in
all other molluscs.
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Phylum Arthropoda (Jointed Appendages Animals)
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MAIN CHARACTERS
* Arthropoda is the largest Phylum of the animal
kingdom including 10, 00000 species of different types of animals.
* The word Arthropods is derived from Greek
Arthos – Jointed and Podos – Foot.
HABIT AND HABITAT
Arthropodes have undergone an adaptive radiation
for aerial, aquatic, terrestrial and parasitic environment. They are widely
distributed in each and every place of the world.
NATURE
* Arthropoda are “bilaterally symmetrical,”
metamerically segmented metazoa.
EXTERNAL FEATURES
* Their body is covered by an exo-skeleton of
“chitin” and protein.
* They possess paired jointed appendages.
* Their metamers are not alike but are
specialized and their number is generally fixed.
* The head is well developed.
INTERNAL FEATURES
* Musculature is not continues but comprises
separates striped muscles.
* The coelomic space in Arthropods is occupied
by the blood vascular system and is thus called “Haemocoel.”
* Digestive tract is complete; mouth and anus
lie at the opposite end of the body.
* Circulatory system is open with dorsal heart
and arteries but without capillaries.
* Respiration through general body surface, by
gills in aquatic forms, trachea or book lungs in terrestrial forms.
* Excretion by “Malpighian tubules” or
Coelomoducts.
* Sexes are generally separate and sexual
dimorphism is often exhibited by several forms.
* Fertilization is internal.
* Development is usually indirect through the
larval stage.
* Nervous system of arthropods is quite similar
to that of annelids and consists of dorsal anterior brain and a double ventral
nerve cord.
CLASSIFICATION OF ARTHROPODA
Phylum Arthropoda is divided into following five
classes:
1. CLASS MEROSTOMATA
* Almost all members of the class Merostomata
are extinct. The only living merostomes, the king Crabs have survived.
* The animals are horse-shoe shaped.
* The long spike like tail that extends,
posteriorly is used in locomotion. It is called “Telson.”
* They feed on mollusks, worms and other
invertebrates that they find on the ocean floor.
* King Crabs a hors-shoe crabs have a tough
“Carapace” jointed to a smaller abdomen.
* E.g:Limulus Polyphemus (King Crab).
2. CLASS ARACHNIDA
* This class includes spiders, scorpions, mites,
ticks and many other terrestrial arthropods.
* The Arachnid body consists of a cephalothorax
and abdomen.
* Cephalothorax is comprised of fused head and
thorax.
* Arachnids have six pairs of jointed
appendages.
* Most Archnids are carnivorous and prey upon
insects and other small arthropods.
* Respiration in archnids takes place either by
trachea or book lungs or by both.
* They are mainly terrestrial arthropods.
* They have no antenna.
* Cephalothorax is non-segmented.
* E.g: Scorpions, Ticks & Mites, Spiders
3. CLASS CRUSTACEA
* They live both in marine and fresh waters.
* A few are terrestrial.
* Crustaceans are unique among arthropods in
possessing two pairs of antenna.
* They always have one pair of mandibles and two
pairs of maxillae around the mouth.
* Mandibles are usually adapted for biting and
chewing. Maxillae are used for holding the food.
* Their body is divided into three distinct
parts, i.e. the head, thorax and abdomen.
* Respiration usually takes place through gills
associated with appendages.
* The sexes are usually separate and the
reproduction is sexual.
* The thoracic and abdominal appendages may be
variously modified for walking, swimming, feeding, respiration or as accessory
reproductive structures.
* E.g: Sacculina (Parasitic Crustacean), Astacus
(Cray-fish), Prawns, Shrimps, Lobsters and Crabs etc.
4. CLASS MYRIAPODA
* All the animals are terrestrial.
* Their body is divided into a head and an
elongated trunk with many segments.
* Each segment bears one or two pairs of legs.
* They are carnivorous /herbivorous.
* Eyes may present or absent.
* E.g: Millipedes and Centipedes etc.
5. CLASS INSECTA (HEXAPODA)
Insecta is the largest class of the animal
kingdom.
HABIT AND HABITAT
* In their adaptive radiation, approximately a
8,50,000 species of insecta have occupied all types of terrestrial habitat.
* Some live in fresh water, however one small
group is marine.
NATURE AND ADAPTATIONS
* The great success of insects can be attributed
partly to the development of flight in them.
* Flight has provided them the great capacity of
dispersal, access to food sources, and favourable habitat and escape from
enemies.
* Corresponding to their number of species,
there exists a huge variation in their structural and biological adaptations.
EXTERNAL FEATURES
* All insects have their body divided into three
well-defined regions i.e. the head, thorax and abdomen.
* There is always a pair of antenna on the head.
* The thorax always consists of three segments:
(a) Prothorax
(b) Mesothorax
(c) Metathorax
* Each thoracic segment bears a pair of legs.
* Head consists of six fused segments and a pair
of compound eyes and mouth parts.
* Abdomen comprises 7-11 segments and devoid of
appendages.
MOUTH PARTS
* The feeding appendages consists of three pairs:
(a) Mandibles
(b) First Pair of Maxilla
(c) Second Pair of Maxilla
* The second pair of maxillae have fused
together to form the “LABIUM,” or lower lip
* The upper lip is formed by the projections
head and is called the “LABRUM.’
* Types:- The mouth appendages have been greatly
modified to form five basic types of pattern:
(i) Biting
(ii) Chewing
(iii) Piercing
(iv) Sucking
(v) Siphoning or Sponging
INTERNAL FEATURES
* Heart is elongated, tubular and divided into
chambers situated in the abdomen.
* Excretion takes place through “Malpighian
tubules.”
* Liver is absent but salivary glands are
usually present.
* Respiration is by “TRACHEA”. External gills
may be present as accessory respiratory organs in some aquatic insects.
REPRODUCTION
Reproduction is sexual in most insects. However
it takes place parthenogenetically i.e. eggs developing without being
fertilized by sperms in a number of insects e.g: Aphids and Termites etc.
METAMORPHOSIS
* The development of insects after hatching from
egg into adult stage involves considerable growth and in some cases drastic
morphological changes.
* The entire post-hatching development is termed
as “Metamorphosis.”
(A) INCOMPLETE METAMORPHOSIS
* In some insects the immature form that hatch
from the egg are essentially similar in shape to their adults, but are smaller
in size, lack wings and reproductive organs
* They attain adult characters after some growth
period. This type of metamorphosis is called “Incomplete Metamorphosis.”
* Three stages are Egg → Nymph → Adult.
* For example Cockroach, Grasshopper, Bugs etc.
(B) COMPLETE METAMORPHOSIS
* In this type the animal shows following stages
during its complete development: Egg → Larva → Pupa → Adult.
* For example Mosquito, Butter fly, House fly
etc.
ECONOMIC IMPORTANCE OF INSECTS
Insects are of very great importance to man.
BENEFICIAL INSECTS
1. Apis, the honey bees produce honey and also
give wax.
2. Insects bring about the cross-pollination.
3. Bombyx and Eupterote are silk-moths and
produce silk.
4. The larvae of Lucilla and Pharmia are used in
wound healing of bones.
5. Some insects feed upon and destroy harmful
insects.
6. Some insects are Scavengers
HARMFUL INSECTS
1. Many types of mosquitoes, flies, fleas, lice
and bugs transmit diseases to man and animals.
2. Human food is spoiled by cockroaches, ants
and flies.
3. Tinea and Teniola are cloth-moths and destroy
cloths.
4. Tenebrio is mealworm. They eat meal, flour
and grains.
5. Lepisma destroy the books.
6. Termites destroy books and wood.
7. Many insects injurious to crops e.g. Tree
hoppers, Leaf hoppers, Aphids, White flies and bugs.
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Phylum Echinodermata
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GENERAL CHARACTERS
HABIT AND HABITAT
The Echinodermates are exclusively marine
including the largest invertebrate “Giant Squids.”
EXTERNAL FEATURES
* Symmetry usually radial, nearly always
pentamerous.
* Body shape is rounded to cylindrical or star
like.
* Surface of the body is rough.
* Body wall consists of an outer epidermis, a
middle dermis and inner lining of peritoneum.
INTERNAL FEATURES
* Endoskeleton consists of closely fitted plates
forming shell usually called “THECA,” may be composed of separate small
“OSSICLES.”
* Coelom is spacious, lined by peritoneum and
occupied mainly by digestive and reproductive systems.
* Presence of “Water Vascular System” is most
characteristic feature.
* Alimentary tract is usually coiled.
* Circulatory or Haemal or blood lacunar system
is typically present.
* Excretory system is wanting.
* Nervous system is primitive, consists of
ganglionated nerve cord.
* Sense organs are poorly developed.
* Sexes are usually separate.
* Reproduction is usually sexual, fertilization
is external.
WATER CANAL SYSTEM
Water canal system is unique in possessing an
internal closed system of canals containing a watery fluid.
REGENERATION
Regeneration of lost part is common
IMPORTANCE OF WATER CANAL SYSTEM
These canals are provided with tubular
protrusions called “Tube Feet,” which serve a number of functions like
locomotion, anchoring to hard surfaces, grabbing the prey, diverting food
particles towards mouth and in some cases also respiration. The watery fluid is
drawn from the surrounding water through a perforated disc called the
“Madreporite.”
EXAMPLE
Star Fish, Brittle stars, Sea urchins,
Sea-cucumbers, Sea-Dollar, Sea-lilies and Feather stars.
LARVA
Bipinnaria larva
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Phylum Hemichordata
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GENERAL CHARACTERS
* It is a small group of animals, which include
about 90 species.
* They are soft-bodied animals, which usually
live in shallow “U” shaped burrows in the sandy or muddy sea bottom.
EXTERNAL FEATURES
* They are cylindrical or vase shaped animals,
bilaterally symmetrical and lack any segmentation.
* They may be solitary or colonial and usually
range between a few millimeter and 250 cm in length.
* Sexes are separate in hemichordates.
INTERNAL FEATURES
* Circulatory system is open and coelom is
divided into three chambers.
* A dorsal and a ventral nerve cord are present.
LARVA
Tornaria larva
EXAMPLE
Balanoglossus, Acron worm etc.
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Nutrition
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* Nutrition in Plants
* Human Digestive System
* Digestive System of Cockroach
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Nutrition in Plants
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CLASSIFICATION ON THE BASIS OF MODE OF NUTRITION
Plants can be divided into two groups on the basis of their mode of nutrition.
1. AUTOTROPHIC
2. HETEROTROPHIC
1. AUTOTROPHIC NUTRITION
DEFINITION
“Autotrophic nutrition is the type of nutrition in which organic compounds are
manufactured from available inorganic raw material taking from surroundings”.
In autotrophic nutrition, the nutrients do not require to be pretreated or
digested before taking them into their cells.
TWO METHODS OF AUTOTROPHIC NUTRITION
On the basis of source of energy, autotrophic nutrition can be sub-divided into
following sub-types.
(I) Phototrophic nutrition
(II) Chemotrophic nutrition
I. PHOTOTROPHIC NUTRITION
DEFINITION
“The type of autotrophic nutrition is which organic molecules are manufactured
from simple inorganic molecules by using light energy as a source is called
Phototrophic Nutrition”.
EXAMPLE
a. Green Plants
b. Photosynthetic Bacteria
(I-A) PHOTOTROPHIC NUTRITION IN GREEN PLANTS
Green plants are very prominent example of phototrophic nutrition. They prepare
the food by the process of photosynthesis.
RAW MATERIAL
The raw material needed by these organisms are
(1) CO2 AND H20
They provide carbon, hydrogen and oxygen for the synthesis of organic
molecules.
(2) MINERALS
The minerals like Nitrogen, Phosphorus and Sulphur and Magnesium are also
required.
(3) GREEN PIGMENTS
The green pigments i.e. Chlorophyll a, b, or others are also required to absorb
the energy from universal source of light.
(4) LIGHT
In the presence of sun light nutrients are used to synthesis the energy rich
compounded (CHO) This process is called “PHOTOSYNTHESIS”.
This process can be represented by equation as follows.
6CO2 + 12H2O -> C6H12O6 + 6O2 + 6H2O
(I-B) PHOTOTROPHIC NUTRITION IN PHOTOSYNTHETIC BACTERIA
Photosynthetic bacteria are unique because they are the only organisms which
are capable of synthesizing the carbohydrate food without chlorophyll “a”.
DIFFERENCES BETWEEN PHOTOSYNTHETIC BACTERIA AND GREEN PLANTS
Photosynthesis in bacteria is different from green plants. Some differences are
* Photosynthetic bacteria usually grow in sulphide spring where H2S is normally
present.
* Hydrogen is provided by H2S instead of H2O.
* Free oxygen is not released as a by product in bacterial photosynthesis.
* The process takes place at low expenditure of energy.
TWO TYPES OF PHOTOSYNTHETIC BACTERIA
There are two types of photosynthetic bacteria.
(1) THOSE IN WHICH “S” IS RELEASED AS BY PRODUCT
These bacteria use H2S as donor of hydrogen. Light splits hydrogen sulphide.
Hydrogen combines with CO2 to form H2O.
2H2S + CO2 -> (CH2O)n + H2O + 2S
EXAMPLES
Purple Sulphur Bacteria ® which use BACTERIO CHLOROPHIL & CARETENOID as
photosynthetic pigments.
(2) THOSE IN WHICH “S” IS NOT RELEASED AS BY PRODUCT
These bacteria use H2S as Hydrogen donor where as sulphur is not the by product
in their case.
EXAMPLES
* PURPLE NON-SULPHUR BACTERIA
* BROWN NON-SULPHUR BACTERIA
Both of these contain “BACTERIO CHLORPHYLL” as photosynthetic pigments.
(II) CHEMOTROPHIC NUTRITION
DEFINITION
“The mode of autotrophic nutrition in which organic molecules are manufactured
from simple inorganic molecules by using energy produced by the oxidation of
certain inorganic substances such as ammonia, nitrates, nitrites, ferrous ions,
H2S and etc. This type of nutrition is called CHEMOTROPHIC NUTRITION and
process of manufacturing food is called CHEMOSYNTHESIS."
Mainly Bacteria are
AMMONIA USING BACTERIA
They derive their energy by oxidation of Ammonia.
NH4+ + O2 -> 2NO2 + 2H2O + 4H+ + energy
BACTERIA CONVERTING NITRITES TO NITRATES
2NO2 + O2 -> 2NO3- + energy
IMPORTANCE OF CHEMOSYNTHETIC BACTERIA
The chemosynthetic bacteria that act on nitrogen compounds do play an important
role in the maintenance of nitrogen balance in the life system.
2. HETEROTROPHIC NUTRITION IN PLANTS
DEFINITION
“Plants which are not capable of manufacturing their own organic molecules
entirely or partially depend for these organic molecular are called
“HETEROTROPHIC PLANTS”
CLASSIFICATION OF HETEROTROPHIC PLANTS
On the basis of type of organisms on which heterotrophic plants depend, they
can be classified into following two classes.
1. PARASITC PLANTS OR PARASITES
2. SAPROPHYTIC PLANTS OR SAPROPHYTES
==1. PARASITES
DEFINITION
"Those heterotrophic plants which depend on living plants and animals for
their nutritional requirements are known as PARASITES."
TYPES OF PARASITES
Parasitic plants can be divided into following types.
A. Obligate or total parasites.
B. Facultative or partial parasites.
1.A TOTAL PARASITES
DEFINITION
Those parasites which depend for their nutrition entirely on other living
organisms
CLASSIFICATION OF TOTAL PARASITIC ANGIOSPERMS
Total or obligate parasitic angiosperms are broadly classified into
* Total stem parasite
* Total root parasite
TOTAL STEM PARASITES
DEFINITION
“Those parasitic plants which depend entirely on the stems of other plants are
called “Total stem Parasites”
EXPLANATION
These plants send HAUSTORIA (specialized structures for absorbing nutrients in
parasitic plants) inside the tissue of host. The xylem of parasite comes in
contact with xylem of host and phloem of parasite to phloem of host. Through
xylem it sucks the water and nutrients, through phloem prepared organic material.
The host plant eventually dies off due to exhaustion.
EXAMPLE
CUSCUTA (AMER-BAIL)
TOTAL ROOT PARASITES
DEFINITION
"Those parasitic plants which suck their nutritional requirements from the
roots of host are called “Total root parasites”.
EXAMPLES
* OROBANCHE -> attacks the roots of the plants belonging to families
Cruciferae and Solanaceae
* CISTANCHE -> Parasitizes on the roots of Calatropis.
* STRIGA -> Found as parasite on the roots of sugar cane
(1.B)PARTIAL PARASITES
DEFINITION
“Those parasite plants which depend for their nutritional requirements
partially on other living organisms are called Falcultave or partial
parasites."
CLASSIFICATION OF PARTIAL PARASITIC ANGIOSPERMS
Partial parasitic angiosperms can be broadly classified into
* PARTIAL STEM PARASITE
* PARTIAL ROOT PARASITE
PARTIAL STEM PARASITES
DEFINITION
Those partial parasites whose haustoria penetrate in the stem of the host and
suck their nutrition from vascular tissues of stem are called PARTIAL STEM
PARASITE
EXPLANATION
LORANTHUS, is a partial stem parasite. It has thick green leaves, a woody stem
and elaborated haustorial system. It can manufacture some of its food with the
help of nutrients and water absorbed from host plants. The seeds get stuck upto
the stem of host plant and germinates sending its haustoria in the tissues of
the host.
EXAMPLES
* LORANTHUS -> found on shrubs, roseaceous tree, Bauhinia and mango
* VISCUM -> produce haustorial branches for an internal suckling
system.
* CASSYTHA FILLIFORMIS -> found in tropics
PARTIAL ROOT PARASITES
EXAMPLE
The examples of this category are rare.
One important example is
* SANDLE WOOD TREE
SAPROPHYTES
DEFINITION
“Those plants which depend for their nutrition on dead or rotten organic remains
of plants or animals are called as SAPROPHYTES”
or
“Plants which break up complex dead food material into simple compounds and use
them for their growth and development are called as SAPROPHYTES.”
TYPES OF SAPROPHYTES
Saprophytes can be divided into two types:
1. Total Saprophytes
2. Partial Saprophytes
1. TOTAL SAPROPHYTES
DEFINITION
“Those plants which depend entirely for their nutrition on dead organic matter
are called Total Saprophytes.
2. PARTIAL SAPROPHYTES
DEFINITION
“Those plants which depend partially on dead organic matter are called Partial
Saprophytes.”
EXAMPLES OF SAPROPHYTES
There are some examples of Saprophytes among flowering plants.
1. Neothia (bird’s net or orchid)
2. Monotrapa (Indian Pipe)
In both of these cases, the roots of plant form a Mycorhizzal Association with
fungal mycelium to help in absorption process.
SPECIAL MODE OF NUTRITION
CARNIVOROUS OR INSECTIVOROUS PLANTS
DEFINITION
“The plants which have as their prey, insects and small birds are called Carnivorous
plants. It is a special mode of nutrition in partially autotrophic and
partially heterotrophic plants."
EXPLANATION
Partially autotrophic and partially heterotrophic plants are carnivorous, which
possess the green pigments and can manufacture CHO but are not capable of
synthesizing nitrogenous compounds and proteins. For their nitrogen
requirement, carnivorous plants have to depend on insects, which they catch and
digest by specific devices developed in them. J.D. Hooker suggested that the digestion
of carnivorous plants is like that of animals.
COMMON AREAS WHERE THESE PLANTS GROW
These plants commonly grow in areas where nitrogen is deficient due to
unfavourable atmosphere for nitrifying bacteria but favourable atmosphere for
denitrifying bacteria.
SOME COMMON EXAMPLES
1. PITCHER PLANT
In Pitcher plant leaf is modified into pitcher like structure which is insect
trapping organ.
EXAMPLES
Common examples are :
* Nepenthes
* Sarracenia
* Cephalotus
* Neliamphora
* Darling tonia
2. DORSERA INTERMEDIA OR SUNDEW
This plant has half a dozen prostrate radiating leaves, which bear hair like
tentacles each with gland at its tip. The insects attracted by plant odour are
digested.
3. DIONAEA MUSCIPULA OR VENOUS FLY TRAP
Most well known of all carnivorous plants. It has a resette of prostrate
radiating leaves with inflorescence in the centre. The petiole of leaf is
winged and lamina has two halves, with mid-rib in the centre. Each half has
12-20 teeth. In the centre of dorsal surface of lamina are numerous secretory
glands, three hairs projecting out, which are sensitive to touch.
4.ALDROVANDA (WATER FLY TRAP)
It is a root less aquatic plant with floating stem. It has ressettes of
modified leaves, which have two lobed mobile lamina having teeth at the margin
and sensitive jointed hairs and glands on the surface.
5. UTRICULARIA OR BLADDER WORT
It is a root less plant having branched slender stem. Leaves are also much
divided and some leaflets are modified into bladder like traps of about 1/16 to
1/8 inches in diameter.
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Human
Digestive System
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DIGESTION
“It is the process by which large complex
insoluble organic food substances are broken down into smaller simpler soluble
molecules by the help of enzymes”.
Digestion in man is mechanical (break down) as
well as chemical (enzymatic hydrolysis)
NUTRITION
HETEROTROPHIC, i.e. man is dependent upon ready
made food.
TYPE OF DIGESTION
EXTRACELLULAR, i.e. digestion takes place
outside the cells but within GIT.
TYPE OF DIGESTIVE SYSTEM
TUBE LIKE DIGESTIVE SYSTEM, i.e,
* Digestive cavity is separated from body
cavity.
* It has both openings, mouth and anus.
* “Complete” digestive sytem
This one way tube is known as GASTRO-INTESTINAL
TRACT (GIT)
ORGANS OF GASTRO-INTESTINAL SYSTEM
The adult digestive system is a tube
approximately 4.5m (15ft) long and comprises of
(A) G I T
1. MOUTH
2. ORAL CAVITY -> TEETH, TONGUE
3. PHARYNX
4. OESOPHAGUS
5. STOMACH
6. SMALL INTESTINE -> DUODENUM, JEJUNUM,
ILEUM
7. LARGE INTESTINE -> CAECUM, RECTUM, COLON
8. ANUS -> PAROTID
(B) ASSOCIATED GLANDS
1. SALIVARY GLANDS -> SUBLINGUAL,
SUBMANDIBULAR
2. LIVER
3. PANCREAS
(1) MOUTH
The anterior or proximal opening of gut, which
is bounded anteriorly by lips. It opens into oral cavity.
FUNCTION
1. Lips close the mouth.
2. Lips also help in ingestion.
(2) ORAL CAVITY
It is a wide cavity supported by bones of skull
BOUNDARIES
* Cheeks form side walls.
* Tongue forms floor
* Palate forms roof
* Jaws form roof boundary of mouth.
+ JAWS
Upper jaw is fixed while lower jaw is moveable.
Both jaws bear teeth.
CONTENT OF CAVITY
Teeth and Tongue
+ TEETH
“The hard calcified structures, meant for
mastication (chewing)”
NUMBER OF SETS
Humans have 2 sets of teeth ® DIPHYODONT
(1) DECIDUOUS
The 20 teeth of first dentition, which are shed
and replaced by permanent teeth.
(2) PERMEMANT
The 32 teeth of second dentition, which begin to
appear in human at about 6 year of age. It consisting of 8 incisors, 4 canines,
8 premolars and 12 molars.
+ Molars are absent in deciduous set.
HETERDONT They are embedded in gums ->
THECODONT
STRUCTURE OF A TOOTH
Each tooth consist of 3 parts
1. CROWN
2. NECK
3. ROOT
FUNCTIONS
1. Incisors are cutting and biting teeth. Their
flat sharp edges cut food into smaller pieces.
2. Canines are pointed teeth and poorly
developed in humans. They are used in tearing, killing and piercing the prey.
3. Premolars and Molars are grinders and used
for crushing the food.
4. Mastication increases surface are of food for
action of enzymes.
5. If one attempt to swallow a food particle too
large to enter ocsophagus, it may block the trachea and may stop ventilation.
“DENTAL DISEASES”
PLAQUE
“A mixture of bacteria and salivary materials”
OR
* “A soft thin film of food debris, mucin and
dead epithelial cells deposited on teeth, providing medium for growth of
bacterias”
* Plague plays an important role in development
of dental caries, periodontal and gingival disease. Calcified plaque forms
dental calculus.
PERIODONTAL DISEASES
Accumulation of plaque causes inflammation of
gums. Continuous inflammation may spread to the root of tooth and destroy
peridental layer. Eventually tooth becomes loose and falls off or may have to
be extracted.
DENTAL CALCULUS
Plaque combine with certain chemicals in saliva
which become harden and calcified forming deposits of calculus which cannot be
removed by brushing.
DENTAL CARIES
When bacteria of plaque converts sugar of food
into acid, the enamel (hardest substance of body, covers dentin of crown of
teeth) is dissolved slowly. When dentine and pulp are attached, produce
toothache and loss of teeth.
FACTOR CAUSING DENTAL CARIES
* Prolonged exposure to sugary food stuff.
* Disturbance of saliva composition
* Lack of oral hygiene
* Low levels of fluoride in drinking H2O
PREVENTION
* Add ‘flouride’ in drinking H2O or milk
* Take ‘flouride’ tablet
* Use ‘flouride’ tooth paste.
TONGUE
Tongue is a muscular fleshy structure forming
floor of oral cavity. Tongue has
* a root
* a tip and
* a body
It is attached posteriorly and free anteriorly
TASTE BUDS
Taste buds respond to sweet, salt, acid and
bitter taste, only when these substances are dissolved in H2O of saliva.
Taste buds are most numerous on sides of vallate
papillae. They are absent on mid dorsal region of oral part of tongue.
TONGUE PAPILLAE
Papillae are projections of mucous membrane
which gives characteristic roughness to the tongue. These are of 3 types
* VALLATE PAPILLAE
* FUNGIFORM PAPILLAE
* FILLIFORM PAPILLAE
FUNCTIONS
1. Its function is ‘Spoon-like’.
2. It mixes the masticated food with saliva
3. It helps in swalloing
4. It helps in sucking and testing food.
SALIVARY GLANDS
3 pairs of salivary glands.
(1) PAROTID
Lies at base of pinnae.
It is supplied by IX cranial nerve.
(2) SUB LINGUAL
* Lies at base of tongue.
* Supplied by VII cranial nerve.
(3) SUB MANDIBULAR
* Lies at base of lower jaw.
* Supplied by VII cranial nerve
FUNCTION
These three pairs produce about 1.5dm3 of saliva
each day.
These glands are supplied by Parasympathetic
Nervous System. Fibers of parasympathic N.S lie in Cranial nerves. These nerves
increase their secretion.
SALIVA
It is a watery secretion containing 95% H2O,
some mucous, amylase and Lysozyme enzyme.
* Salivation is brought about by
“Parasympathetic Nervous System.”
* Saliva is secreted in response to the sight,
thought, taste or smell of food.
FUNCTIONS
1. Mucous of Saliva moistens and lubricates the
food particles prior to swallowing.
2. Salivary Amylase or Ptylin begins digestion
of starch, first to dextrins and then to maltose (dissacharide).
3. Lysozyme destroys the oral cavity pathogen bacteria.
It has a cleansing action.
4. Water in Saliva, dissolve some of the
molecules in food particle then they react with chemo receptors in taste buds,
giving sensation of taste, hence, the H2O enables taste buds to respond.
5. Saliva is fully saturated with calcium and
this prevents decalcification of teeth.
6. Saliva makes speech possible by moistening
the mouth; it is not possible to talk if the mouth is dry.
7. It acts as a lubricant and enables a bolus (a
rounded mass of semi-solid, partially digested food particles stick together by
mucus) to be formed. The tongue pushes bolus into pharynx.
3. PHARYNX
The musculo-membranous passage between mouth and
posterior nares and the larynx and oesophagus.
OPENINGS
It contains opening of oesophagus, glottis,
Eustachian tube and internal nostrils.
PARTS OF PHARYNX
NASOPHARYNNX
The part above the level of soft palate is
NASOPHARYNX, which communicates with auditory tube.
OROPHARYNX
It lies between soft palate and upper edge of
the epiglottis.
HYPOPHARYNX
It lies below the upper edge of epiglottis and
opens into larynx and oesophagus.
FUNCTION -> SWALLOWING
Swallowing in its initial stages is voluntary
but involuntary afterwards.
MECHANISM
1. As the bolus of food moves into the pharynx,
the soft palate is elevated and lodges against the back wall of pharynx sealing
the nasal cavity and preventing food from entering it.
2. The swallowing center inhibit respiration,
raises the larynx and closes the glottis (opening between vocal cords), keeping
food from getting into trachea.
3. As the tongue forces the food further back
into the pharynx, the bolus tilts the epiglottis backward to cover the closed
glottis.
4. This pharyngeal act of swallowing lasts about
1 second.
4. OESOPHAGUS
This is a narrow muscular tube of about 25cm
long. It connects pharynx to stomach. It passes through the thoracic cavity and
penetrates the diaphragm, then it joins the stomach a few cms below the
diaphragm.
MUSCLES OF OESOPHAGUS
* Upper-one third is surrounded by skeletal
muscles.
* Lower two-third is surrounded by smooth
muscles.
SPHINCTERS (MUSCULAR VALVES)
1. Skeletal muscles, just below pharynx
surrounding oesophagus form Upper Oesophageal Sphincter.
2. Smooth muscles in last 4 cm of oesophagus
forms Lower Oesophageal Sphincter. It seals the exit of food.
FUNCTION
It conveys the food or fluid by Peristalsis.
PERISTALSIS
Alternate rhythmic contraction and relaxation
waves in the muscle layers surrounding a tube are called Peristaltic Waves.
It is the basic propulsive movement of GIT.
STIMULUS
Distention of oesophagus.
TIMING
An oesophageal peristaltic wave takes about ‘9
sec’ to reach stomach. Bolus is moved toward stomach by progressive peristaltic
wave which compresses the lumen and forces the bolus ahead of it.
ANTI-PERISTALSIS
Peristalsis in opposite direction, i.e. from
stomach towards pharynx.
STIMULUS
* Early stages of GIT irritation.
* Over distention.
VOMITING
Anti peristalsis begins to occur, some minute
before vomiting appears. The initial events of anti peristalsis may occur
repeatedly without vomiting, called RETCHING. 1. Vomiting begins with a deep
inspiration, closure of glottis and elevation of soft palate.
2. Abdominal and thoracic muscles contract,
raising intradominal pressure.
3. Stomach is squeezed, lower oesophageal
sphincter relaxes allowing expulsion of stomach content into oesophagus in form
of VOMITUS.
5 OESOPHAGUS
Stomach is a hollow, muscular, distensible bag
like organ.
LOCATION
Lying below the diaphragm on the left side of
abdominal cavity.
STRUCTURE
It has 3 regions.
1 CARDIAC REGION
This is the anterior region which joins the
oesophagus through a cardiac sphincter. It has muscous glands which helps in
lubrication of food.
2 BODY
The middle portion is body of stomach. The part
to the left and above the entrance of oesophagus is called FUNDUS of stomach.
Body of stomach contain gastric glands. Gastric glands contain 3 types of
cells.
MUCOUS CELLS
* These cells are present at opening of gastric
glands and secrete mucous.
* It lubricates the food and passage.
* It also protects the epithelium from self
digestion by pepsin.
OXYNTIC / PARIETAL CELLS
* They lie deeper within the glands and secrete
dilute HCl having a pH of 1.5 – 2.5.
* Kills microbes
* Solublization of food particles.
* Activate the inactive enzyme pepsinogen into
Pepsin.
CHIEF CELL / ZYMOGEN CELLS
* Deeper in the glands and secrete enzyme
precursor Pepsinogen.
* After converting into Pepsin, it acts upon
proteins and convert them into short chain polypeptides, Peptones.
The collective secretion of the above mentioned
3 cells is called as GASTRIC JUICE
PYLORIC REGION
The posterior region is the terminal narrow
pyloric region or Antrum. It opens into duodenum through pyloric sphincter / pylorus.
ITS SECRETION -> GASTRIN
This region does not secrete acid. It secretes
mucous, pepsinogen and a hormone GASTRIN. Endocrine cells which secrete GASTRIN
are scattered throughout epithelium of antrum.
STIMULUS
Partially digested proteins.
ACTION
Activate gastric glands to produce gastric
juices.
“RENIN”-ADDITIONAL ENZYME IN INFANT
In infants, RENIN is secreted which curdles the
milk.
FUNCTION OF STOMACH
(1) STORAGE OF FOOD
Pylorus acts as a valve and retain food in the
stomach for about 4 hours. Periodic relaxation of pylorus releases small
quantities of chyme into duodenum.
(2) MECHANICAL DIGESTION
The weak peristaltic waves also called mixing
waves move along the stomach wall once every 20 seconds. These waves not only
mix the food with secretions but also move mixed contents forward.
(3) CHEMICAL DIGESTION
Gastric juice converts food to a creamy paste
called CHYME.
6. SMALL INTESTINE
The small intestine is a coiled tube
approximately 6 meters long and 2.5 cm wide, leading from stomach to large
intestine. It fills most of the abdominal cavity.
DIVISIONS
There are 3 divisions.
A. DUODENUM
It begins after pyloric stomach and ends at
jejunum. Its length is about 30cm.
SECRETION
Pancreatic juice from pancreas by pancreatic
duet and bile from gall bladder by common bile duct act on chyme from stomach.
Both ducts open via a common opening in duodenum.
BILE
SYNTHESIS, STORAGE AND SECRETION
Bile is made in liver and enters the duodenum
via the bile duct. It stores in gall bladder.
COLOUR
Bile is yellow in colour but changes to green
due to exposure to air.
CONSTITUENT
* Water.
* Bile Salts
+ BILE SALTS
These are sodium salts of compounds of
cholestrol. NaHCO3 is also present which neutralizes the acidity of gastric
juice and make the chyme alkaline.
The main bile salts are for emulsification of
fats.
EMULSIFICATION Break down of large fat particles
into small droplets so that they can mix well with H2O to form emulsions.
+ BILE PIGMENTS
BILIRUBIN and BILIVERDIN are excretory products
formed by breakdown of haemaglobin of worn out RBCs in the liver.
ACTION OF ‘CHOLECYSTOKININ (CCK)’
CCK is a hormone and produced by cells of small
intestine.
STIMULI FOR HORMONE RELEASE
Fatty food in duodenum.
ACTION
CCK is released in blood and reaches to gall
bladder and causes it to contract. Due to contraction of gall bladder, bile
enters the duodenum.
‘PANCREATIC JUICE’
Pancreatic juice is produced in pancreas by its
exocrine function and secreted via pancreatic duct. It is a colourless fluid.
ACTION OF SECRETIN
Secretion is also a hormone and produced by
cells of small intestine.
STIMULI
Acid (HCl) carried with chyme in small
intestine.
ACTION
It increases the secretion of pancreatic juice
and also increases bicarbonate secretion in bile.
CONSTITUENTS
(1) TRYPSIN (PROTEASE)
It is secreted in an inactive form called
Trypsinogen which is activated by action of an enzyme produced by duodenum
called enterokinase.
ACTION
Break proteins and long chain polypeptides into
small peptide fragments.
(2) CHYMOTRYPSIN (PROTEASE)
It is also secreted in inactive form,
Chymotrypsinogen which is converted into chymotrypsin by action of Trypsin.
ACTION
Converts casein (milk proteins) into short chain
peptide.
(3) AMYLASE
It is similar to salivary amylase. It acts on
polysaccharides (Glycogen and Starch) and convert them into maltose (a
disaccharide).
(4) LIPASE
It acts on emulsified fat droplets. It splits
off lipid into fatty acid and glycerol, hance the digestion of fat is completed
in duodenum.
(B) JEJUNUM
It extends from duodenum to illeum. It is 2.4
meters long. Here the digestion of food is completed.
COLLECTION OF PEPTIDASES, EREPSIN
Peptidases complete the breakdown of polypeptide
into amino acids.
NUCLEOTIDASE
It converts nucleotides into nucleoside. End
products of digestion, i.e, monosaccharide and A.As are liberated in lumen of
small intestine for absorption in ileum.
(C) ILEUM
It is the last and longest part of small
intestine. Its length is about 3.6 meters long. It contains digested food in
true solution form.
STRUCTURE
The inner wall (Mucosa and Submucosa) of small
intestine is thrown into various folds. These folds have finger-like
microscopic projections called villi.
VILLI
Each villus is lined with epithelial cells
having microvilli on their free surfaces.
Their walls are richly supplied with blood
vessels and lymph vessels called Lacteals. Some smooth muscles are also present
in villi.
MECHANISM OF ABSORPTION
Major function of ileum is absorption of
digested food, which is facilitated by highly folded inner wall of intestine
with villi on their surfaces.
This increases the absorptive area. Villi are
able to move back and forth due to muscle fibers in them.
* The monosaccharide and A.As are absorbed into
blood capillaries by Diffusion or Active Transport.
* Fatty acid and glycerol enter epithelial cells
of villi, covert into triglycerols and enters Lacteals and pass into blood
stream.
BLOOD DRAINAGE OF INTESTINE
All capillaries converge to form hepatic portal
vein, which delivers absorbed nutrients to liver.
7. LARGE INTESTINE
Small intestine opens into large intestine,
which is a large diameter tube about 6.5 cm. It is not coiled by relatively has
3 straight segments.
+ Caecum
+ Colon
+ Rectum
+ CAECUM
Caecum is a blind ended pouch placed in the
lower right side of abdominal cavity. It gives a 10cm long finger like
projection, Appendix. Appendix is a vestigial organ, i.e. an organ present in
rudimentary form and has no function but has well developed function in
ancestors.
FUNCTION
Symbiotic bacteria, present in caecum, help in
digestion of cellulose, which is not digested by man, as enzyme for digestion
is absent.
+ COLON
Colon is longest part and has 3 regions :
+ Ascending colon
+ Transverse Colon
+ Descending Colon
-> SIGMOID COLON is terminal part of
Descending Colon.
FUNCTION
Inorganic salts, water and mineral absorbed in
colon. Some metabolic waste products and excess calcium of body as salts are
excreted into large intestine. Each day 500 ml of intestinal content enter the
colon and during its passage the amount reduced to 150 ml due to absorption of
H2O.
+ RECTUM
Rectum is last portion, it stores faeces for
some time.
When the faeces enter into rectum, it brings
about a desire for defecation. The process by which faeces passes out is called
Egestion.
SYMBIOTIC BACTERIA
Many symbiotic bacteria in large intestine
provide the body with a source of vitamin and A.As, especially vitamin B
complex and K, which are absorbed in blood stream. Administration of
Broad-spectrum antibiotics destroys these bacteria and a vitamin deficiency
results, which is then make up by vitamin intakes.
8. ANUS
External opening of digestive system is ANUS.
SPHINCTERS
Two sphincters surround the anus:
+ Internal Sphinter -> made up of smooth
muscle and under Autonomic control (involuntary control).
+ Outer Sphincter -> made up of skeletal
muscle and under Somatic Control (voluntary control).
FAECUS
Faecus consists of:
Dead bacteria, cellulose, Plant fibers, dead
mucosal cells, mucous, cholesterol, bile pigment derivatives and H2O.
(DIAGRAM “DIGESTIVE SYSTEM” FROM BOOK XI)
9. LIVER
Liver is the largest organ and gland of body. It
weighs about 1.5 kg . It is also called ‘HEPAR’.
COLOUR
It is reddish brown in colour.
LOCATION
It lies below the diaphragm on right side.
LOBES OF LIVER
Liver has 2 lobes, i.e. Right and Left. Left is
further divided into two lobes.
FUNCTIONS OF LIVER
‘AS A METABOLIC FACTORY’
It maintains the appropriate level of nutrients
in blood and body. It is performed in 3 ways.
A. GLUCOSE METABOLISM
1. Additional (Surplus) Glucose is converted
into Glycogen by action of INSULIN after every meal. This is called
Glycogenesis.
2. Glycogen is splitted into Glucose for body
needs. This is called Glycogenolysis.
3. New glucose for body requirement is formed by
non-carbohydrate compounds. This is called Gluconeogenesis.
B. A.AS METABOLISM
A.As are also stored after deamination (removal
of NH2 group), which forms Urea.
C. FATTY ACID METABOLISM
It also processes F.As and stores the products
as Ketone Bodies, which are released as nutrients for active muscles.
‘AS A DETOXIFICATION CENTER’
Poisons and toxic substances, which can harm the
body, are degraded into harmless compounds. It excrete out bile pigments and
waste products.
‘AS A STORAGE ORGAN’
It stores vitamins and also produces proteins
and coagulating factors of blood.
GALL BLADER
It lies on undersurface of liver, a pear shaped
organ.
FUNCTION
It concentrates and stores the bile secreted by
liver.
BILIARY TRACFT
Two hepatic ducts from liver bring bile and join
the cystic duct from gall bladder. This form common bile duct, which joins
Pancreatic duct coming from pancreas bringing pancreatic juice. These 2 ducts
open into duodenum at same opening.
10.PANCREAS
A large elongated gland situated transversely
behind the stomach, between spleen and duodenum.
PARTS OF PANCREAS
HEAD
It is the right extremity and directed
downwards.
TAIL
Left extremity is transverse and terminates
close to spleen.
BODY
The main portion in middle.
DUCT
Pancreatic duct opens into duodenum with common
bile duct and delivers pancreatic juices.
WORKING AS A GLAND
It works both as an endocrine and exocrine
gland.
ENDOCRINE PANCREAS
Endocrine part consists of ISLETS OF LANGERHANS.
The islets contain.
α cell (ALPHA)
Produce GLUCAGON which increases blood glucose
level.
β cell (BETA)
Produce INSULIN which reduces blood glucose
level.
Δ cell (DELTA)
Produce Somatostatin (SS) which inhibit the
release of many harmones.
P P cells
Secrete pancreatic polypeptide.
EXOCRINE PANCREASE
The exocrine part consists of pancreatic acini.
Acini are secretory unit that produce and secrete pancreatic juice into
duodenum which contain enzymes essential to digestion.
DISORDERS OF ‘GIT’
(1) DIARRHOEA
Abnormal frequency and liquidity of fecal
discharges. It is the rapid movement of fecal matter through large intestine.
CAUSES
ENTRITIS
It may be caused by infection of intestinal wall
(mucosa) by a virus or bacteria. Due to infection, mucosa becomes irritated and
motility of intestinal wall increases.
CHOLERA
Cholera is a bacterial disease caused by VIBRIO
CHOLERA. It can cause diarrhoea. It causes extreme amount of HCO3-
(bicarbonates ion) and Na and H2O to be secreted in faeces. It may causes
death.
PSYCOGENIC DIARRHOEA
It is caused by nervous tension. In the young
and elderly, diarrhoea may lead to a serious depletion of H2O and inorganic
salts.
(2) DYSENTARY
Acute inflammation of intestines especially of
the colon.
SYMPTOMS
Pain in abdomen, tenesmus (straining), frequent
stool containing blood and mucus.
CAUSES
* PROTOZOA. (like amoebic dysentery)
* PARASITIC WORMS.
* BACTERIA. (like bacillary dysentery)
* CHEMICAL IRRITANTS.
(3) CONSTIPATION
Infrequent or difficult evacuation of faeces. OR
Slow movement of faeces through large intestine.
Faeces becomes hard due to long time available
for H2O absorption.
CAUSE
Irregular bowel habits that have developed
through a life time of inhibition of normal defection reflaxes.
TREATMENT
* Laxatives are used
* Substance which hold H2O with them
(4) PILES
Also called HAEMORRHOIDS Varicose dialatation of
veins occurring in relation to anus, resulting from a persistence increase in
pressure.
EXTERNAL PILES
Venous dialatation covered with modified anal skin.
INTERNAL PILES
Dilatation of veins covered by mucous membrane.
CAUSE
CONSTIPATION
The pressure exerted to defecate stretches skin
with vein and causes dilation.
PREVENTION
Can be avoided by regular habit of defecation
and by use of fiber diet.
(5) DYSPEPSIA
Impairment of the power or function of
digestion, usually applied to epigastria discomfort following meals.
CAUSE
May be due to peptic ulcer.
SYMPTOMS
* Heart burn.
* Flatulence (distended with gas)
* Anorexia, nausea, vomiting with or without
abdominal pair.
FUNCTIONAL / NON-ULCER DYSPEPSIA
Dyspepsia in which symptoms resemble those of
peptic ulcer, although no ulcer is detectable. It is caused by disturbance in
moter function of alimentary tract.
(6) PEPTIC ULCER
Since pepsin, is a protein digesting enzyme, it
may digest the stomach wall, the first part of duodenum or rarely lower part of
oesophagus where stomach juices frequently refluxes. This condition is called
Peptic Ulcers.
* GASTRIC ULCERS
* DUODENAL ULCERS
CAUSES
* Excessive secretion of acid and pepsin.
* It may be hereditary.
* Psychogenic factors.
COMPLICATIONS
Complications of peptic ulcers are perforation,
haemorrhage and obstruction. INVESTIGATIONS
1. Acid output of stomach is studied.
2. Ulcers cavity may be shown up on X-rays after
ingestion of insoluble barium sulphate (Barium meal).
3. It may be seen using optical instrument
passed down through oesophagus (endoscopy)
(7) FOOD POISONING
Also called GASTRO-ENTRITIS
CAUSES
INFECTION
By bacteria, virus, protozoa. ‘Salmonella’
species are very common.
NON-INFECTIOUS
Allergy, irritating food or drink.
SYMPTOMS
Vomiting and diarrhoea within 48 hours.
(8) MAL NUTRITION
Any disorder of nutrition due to unbalanced diet
or due to defective assimilation or utilization of foods.
An organism may be deficient or may receives
excess of one or more nutrients for a long period of time.
UNDER NUTRITION
Deficiency is known as under-nutrition. It is
most common problem of under developed countries.
OVER NUTRITION
Excess is known as over-nutrition. Obesity with
heart problems and reduced life expactency are its symptoms and are more common
in developed countries.
(9) OBESITY AND OVER WEIGHT
Increase in body weight beyond the limitation of
skeletal and physical need as the result of accumulation (excessive) of fat in
the body.
It is the most common nutritional disorder. It
is most prevalent in middle age. It may be hereditary or family tendency over
weight results in rate of mortality.
(10) ANOREXIA NERVOSA
Loss or lack of appetite for food is called
Anorexia.
ANOREXIA NERVOSA
An eating disorder affecting young females,
characterized by refusal to maintain a normal minimal body weight, intence fear
of gaining body weight, intense fear of gaining weight or becoming obese.
Sometimes accompanied by spontaneous or induced vomiting.
(11) BULIMIA NERVOSA
Exclusively found in women and the age of onset
is slightly older than for anorexia.
Recurrent episodes (bouts) of binge
(uncontrolled) eating. Lack of self control over eating during binges.
Attacks occur twice a week and involve rich
foods such as cakes and chocolates and dairy products.
Digestive System of Cockroach
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Cockroach belongs to PHYLUM : ARTHROPODA CLASS :
INSECTA / HEXAPODA
NUTRITION
OMNIVOROUS, i.e. It can eat any kind of organic
matter. They search their food by antennae.
TYPE OF DIGESTIVE SYSTEM
TABULAR DIGESTIVE SYSTEM, i.e. straight slightly
coiled dig tube, open at both ends, complete dig. system.
ORGANS OF DIGESTIVE SYSTEM
+ ALIMENTARY CANAL
It is divisible into 3 parts
1. FORE GUT / STOMODAEUM
- MOUTH
- BUCCAL CAVITY
- OESOPHAGUS
- CROP
- GIZZARD
2. MIDGUT / MESENTERON / VENTRICULUS
- HEPATIC CAECA
3. HIND GUT / PROCTODAEUM
- ILEUM
- COLON
- RECTUM
- ANUS
+ ASSOCIATED GLAND
- SALIVARY GLANDS
1.FORE GUT
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MOUTH
It lies at base of pre-oval cavity which is
bounded by mouth part.
LABRUM / UPPER LIP
Appendage of 3rd head segment.
MANDIBLES
Appendage of 4th head segment. They help in
mastication
MAXILLAE
Appendages of 5th head segment. They pick up and
bring food.
LABIUM / LOWER LIP
Appendages of 6th head segment.
BUCCAL CAVITY
The mouth opens into buccal cavity which is
short and receives the common duct of salivary glands.
Saliva cantain ‘AMYLASE’ which act upon
carbohydrates.
OESOPHAGUS
Buccal cavity opens into pharynx which in turn
opens into oesophagus which is a long and thin tube lying in thorax.
CROP
It is a large thin walled and pear shaped structure
meant for storing food.
GIZZARD
Crop opens into thick walled, rounded gizzard
with muscular chitins lining which is internally produced six teeth for
grinding and straining the food.
2. MID-GUT
It is narrow, short and tubular portion
originate from gizzard. At beginning it receives eight hepatic caeca hanging in
haemocoel (body cavity filled with white colour blood), ending blindly but
opening in gut.
ENZYMES FROM HEPATIC CAECA
They are lined by glandular cells, which secrete
enzymes.
Enzymes from hepatic caeca and mid-gut flow back
into crop where digestion takes place.
ENZYMES
1. PEDTIDASES AND TRYPSIN LIKE ENZYME ->
digest proteins.
2. AMYLASES -> complete digestion of starches
3. LIPASE -> digestion of fats.
Digested food form a bolus and enclosed in a
thin chitinous tube secreted by stomodael valve of gizzard. This covering is
called PERITROPHIC MEMBRANE.
It is permeable to enzymes and digested food.
This membrane protects the lining of mid gut from damage by hard indigestible
components of food.
Digested food is absorbed in mid gut.
3. HIND-GUT
It has a cuticular ectodermal lining.
ILEUM
Short, narrow and muscular ileum. The beginning
of ileum is marked by 60-70 fine and long, greenish yellow MALPHIGIAN TUBULES.
(excretory in function)
COLON
Colon is long, wider and coiled portion of hind
gut
RECTUM
Rectum is broad last part of hind gut. It
absorbs H2O and conserves the much needed H2O from undigested food before
expelling out the faeces.
ANUS
Anus is the last opening of digestive system by
which hind gut opens to outside.
SALIVARY GLANDS
Salivary glands are 2 in number. each present on
the sides of oesophagus. Saliva contain amylase for digestion of carbohydrates
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Transport - XI Zoology
friendsmania.net
* Circulatory System
* Circulation of Blood
* Lymphatic System
* Immune System
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Circulatory System
Friendsmania.net
HUMAN HEART
INTRODUCTION
Heart, the most powerful organ in the
circulatory system is conical, hollow & muscular organ, situated in middle
mediastinum.
POSITION OF HEART
Heart lies in the thoracic cavity between the
lungs slightly towards left, enclosed with in ribcage with the sternum in front
& vertebral column behind.
SIZE & WEIGHT
The heart measures about 3 ½ Inches & weighs
about 300 gm in males & 250 gm in females.
MAIN FUNCTION OF HEART
Heart works continuously like a muscular pump
& pumps the blood to various parts of the body to meet their nutritive
requirements.
COVERING OF HEART PERICARDIUM
Heart is surrounded by a double layered
pericarcdium. The outer layer is called Fibrous pericardium & inner layer
is called as serous pericardium.
PERICARDIAL FLUID
Fluid is secreted in b/w the two layers of
pericardium which is known as pericardial fluid.
FUNCTION
Pericardial fluid acts as LUBRICANT &
reduces friction b/w heart walls & surrounding tissues during beating of
heart.
STRUCTURE OF HEART
Human heart consists of four chambers.
CHAMBERS OF HEART
1. RIGHT ATRIUM
Right Atrium is the right upper chamber of heart
& acts as thin walled low pressure pump.
OPENINGS (INLETS) OF RIGHT ATRIUM
1. Superior Vena Cava
2. Anfenior Vena Cava
3. Coronary Sinus
FUNCTION
It receives venous blood from the whole body
& pump it to the right ventricle through the right atrioventricular
(tricuspid opening) valve.
2. LEFT ATRIUM
Left atrium is upper triangular chamber which is
present posteriorly. It also acts as low pressure pump.
OPENINGS (INLETS) OF LEFT ATRIUM
Two pairs of pulmonary veins.
FUNCTION
It receives oxygenated blood from the lungs
through 4 pulmonary veins and pumps it to the left ventricle through the left
atrioventricular orifice (mitral or bicuspid).
3. RIGHT VENTRICLE
Right ventricle is the right lower chamber of
heart, which is triangular in shape.
OPENINGS OF RIGHT VENTRICLE
- Tricuspids valve
- Pulmonary Aorta through pulmonary valve.
THICKNESS OF WALL
- The wall of right ventricle is thinner than that of
left ventricle in a ratio of 1:3
SIZE OF CAVITY
Cavity of right ventricle is broader than left
because of thin muscular walls, and both of these features are due to the fact
that right ventricle has to pump the blood into lungs only against low pressure
system (i.e. pulmonary circulation).
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FUNCTION
Right ventricle receives deoxygenated blood from
right Atrium and pumps it to the lungs through pulmonary aorta for oxygenation.
4. LEFT VENTRICLE
Left ventricle is the most thick walled chamber
and forms the apex of heart.
OPENING OF LEFT VENTRICLE
- Bicuspid or Mitral valve
- Systemic Aorta through aortic valve.
THICKNESS OF WALL
The walls of left ventricle are 3 times thicker
than those of right ventricle. Blood pressure is 6 times high.
SIZE OF CAVITY
The cavity of left ventricle is narrower than
the right ventricle because of more muscular walls. It is due to the fact that
left ventricle has to pump the blood to the entire body against high pressure
system (Systemic Circulation).
FUNCTION
It receives oxygenated blood from left atrium
& pumps it into the aorta.
INTERNAL STRUCTURE OF VENTRLES
Interior of ventricles show two parts
1. Rough in flowing part
2. Smooth out flowing part
1. ROUGH PART
TRABECULAE CARNEAE
Inflowing part of each ventricle is rough due to
presence of muscular ridges called as Trabeculae carneae.
2. SMOOTH PART
Out flowing part of each ventricle is smooth
which gives origin to pulmonary trunk in right ventricle & Ascending Aorta
in left ventricle.
PAPILLARY MUSCLES
Papillary muscles are the type of Trabeculae
carneae being attached by their bases to ventricular walls, & their apices
are connected to, the cusps of valves through chorda tendinae.
CHORDA TENDINAE:
These are delicate fibrous chords, which connect
the papillary muscles to the cusps of Atriovertritcular valves.
FUNCTION
Chorda Tendinae don’t left the valves open back
into the atria when the ventricles contract.
SEPTUM OF HEART
1. INTERATRIAL SEPTUM
Internally, the right & left atria are
separated by a vertical membranous septum called as Interatrial septum.
2. INTERVENTRICULAR SEPTUM:
The right & left verticals are also
separated by a thick muscular septum called as Interventricular septum.
3. ATRIOVENTRICULAR SEPTUM
Atria lie above & behind the ventricles
& are separated from ventricles by Atrioven-tricular septum.
HEART VALVES
Heart possesses two types of valves, which
regulate the flow of blood with in the heart.
TYPES OF HEART VALVES
1. Atrioventricular valves -> Bicuspid,
Tricuspid
2. Semilunar vlaves -> Aortic valve,
Pulmonary valve
1. ATRIOVENTRICULAR VALVES
INTRODUCTION
Valves, which are present in b/w the Atria &
ventricles are called Atrioventricular valves.
TYPES OF ATRIOVENTRICULAR VALVES
They are of two types.
1. Bicuspid or Mitral
2. Tricuspid.
1. BICUSPID OR MITRAL VALVE
Blood flows from left Atrium to the left
ventricle through left atrioventricular on orifice, which is guarded by bicuspid
or Mitral valves.
CUSPS
It has tow (2) cusps so it is called as
bicuspid.
2.TRICUSPID VALVE
Blood flows from right Atrium to the Right
ventricle through right Atrioventricular orifice, which is guarded by
Tricuspid.
CUSPS
It has 3 cusps so it is called as TRICUSPID.
2. SEMILUNAR VALVES
This is the second category of heart valves,
which guard the emergence of pulmonary & systemic Aorta.
TYPES OF SEMILUNAR VALVES
It has Two Types:
1. Aortic Valve
2. Pulmonary Valve
1. AORTIC VALVE==
This valve guards the Aortic orifice in left
ventricle
CUSPS
It consists of 3 Semilunar cusps.
2. PULMONARY VALVE
This valve guards the pulmonary orifice in right
ventricle.
CUSPS
It also consists of 3 semi lunar cusps.
FUNCTIONS OF VALVES
Heart valves maintain unidirectional flow of the
blood & prevents its regurgitation in the opposite direction
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Circulation of Blood
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CARDIAC CYCLE
Sequence of events which take pace during
completion of one heart beat is called “Cardiac Cycle”
PHASES
(I) DIASTOLE
It is resting period of heart chambers.
II) SYSTOLE
During which heart’s chambers contract. In
cardiac cycle, blood is circulated in whole body.
TYPES OF CIRCULATION
PULMONARY CIRCULATION
In pulmonary circulation following events take
place.
RT. ATRIAL SYSTOL
First the blood from whole systems of body,
except lungs enter in right Atrium through superior and Inferior vena cavae
into the right atrium by atiral systole, blood comes into right ventricle from
right atrium via Tricuspid valve.
RT. VENTRICLE SYSTOLE
After coming of blood into the Rt. Ventricle, it
goes to the lungs via pulmonary trunk by ventricular systole, for oxygenation
of blood by passing through pulmonary valve.
SYSTEMIC CIRCULATION
In systemic circulation, following events take
place.
LEFT ATRIAL SYSTOLE
When oxygenated blood comes into left atrium,
then left atrial sytole causes blood to enter left ventricle through bicuspid
valve
LEFT VENTRICULAR SYSTOLE
When blood reaches here it sends into aorta
through aortic valve to provide blood to body systems.
CARDIAC OUTPUT
The blood volume pump per minute by left
ventricle into the systemic circulation
HEART BEAT
The contraction of heart chambers are known
heart beat which are regular, rhythmic.
Ventricular systole is LUB
Ventricular diastole is DUB
TIME FOR HEART BEAT
0.8 sec is time for one heart beat.
CONDUCTING SYSTEM OF HEART
It consists of
1.AV-NODE
2.SA-NODE
3)AV-BUNDLE
4) PURKINJI FIBERS.
1. SA-NODE
SA NODE found near upper end of superior vena
cava in RT. atrium
PARTS
1. Specialized cardiac Muscles.
2. Autonomic Nerve endings.
FUNCTIONS
It Initiates the contraction of heart chambers
through impulses & also transmit to AV node.
2. AV- NODE
It is found in lower end of RT. Atrium.
Structurally it is smilar to SA-NODE
FUNCTION
It transmit nerve impulses to ventricles for
contraction rhythmically.
3. AV-BUNDLE
AV BUNDLE are the fibers originate from AV node.
The bundle divided into Right AV bundle, Left AV bundle
FUNCTION
It transmit nerve impulses to ventricles.
4. PURKINJI FIBERS
AV bundles red divided into small fibres which
penetrate the ventricle wall also known as purkinji fibers / Bundle of His
small thin fibers.
LEUKEMIA
DEFINATION
“The malignant disorder of increase number of
abnormal leucocytes in blood.”
CAUSE
The cause of leukemia is unknown.
FACTORS
Factors associated with leukemia are
* Ionizing Radiation
* Cytotoxic drugs.
* Retroviruses.
* Genetic
EFFECTS OF DISEASE
* In result of leukemia, normal leucocytes
counts become less.
* This is progressive, and fatal condition which
leads to heamorrhage or infection
THALASSEMIA
DEFINITION
“Genetically impaired globin chains formation
leads to impaired or defected formation of hemoglobin.”
GENETIC DISEASE
Thalassemia is a genetic disorder, it may be
1. Hetrozygous /Mild thalassemia:
2. Homozygous.
TYPE
* BETA - Thalassemia
* α - Thalassemia
BETA-THALASSEMIA
When globin chain is impaired or defected. It is
most common one.
ALPHA-THALASSEMIA
when α-thalassemia globin chain of (HB)
hemoglobin is defected.
KINDS OF THALASSEMIA
THALASSEMIA MINOR
When thalassemia is of heterozygous type with
mild anemia.
THALASSEMIA MAJOR
When thalassemia is of homozygous type with
profound hypochromic anemia. It is more common in children & results with
enlargement of kidney.
REMEDY
The only remedy is transfusion of blood at
regular intervals.
CVD CARDIOVASCULAR DISEASE
Diseases of heart, blood vessels and blood
circulation are generally term as CVD.
ATHEROSCLEROSIS
The disease of arterial wall with lose of
elasticity, thickness of inner wall causing narrowing of lumen, results in
impairing of blood flow.
ATHEROMATOUS PLAQUES
The narrowing is due to formation of fatty
lesions called atheromatous plaque in inner lining of arteries.
COMPONENTS OF PLAQUE
These plaques consist of
* LDL-LOW DENSITY LIPO PROTEINS
* DECAYING MUSCLES CELLS
* FIBROUS TISSUE
* PLATELETES
* CLUMP OF BLOOD
CAUSES
Smoking, Hypertension, Obesity, Diabetes
(Severe), family history of arterial disease
EFFECTS
Atherosclerosis produces no symptoms until the
damage to artery is so severe that it restricts blood flow.
ANGINA PECTORIS
If blood flow to heart muscles is restricted
causes (cell damage) necrosis called angina pectoris. Pain in chest, arm, or
jaws usually during exercise.
THROMBUS FORMATION
The formation of blood clot with in the intact
blood vessel initiated by atheromatous plaque.
REASON FOR THROMBUS FORMATION
Due to formation athromatous plaque loss of
elasticity, intact blood vessel get destroyed, blood from vessel wall comes out
& later change to blood clot and blocks the lumen of small arteries.
RESULT OF THROMBUS FORMATION
Initially thrombus block the lumen partially
result in decrease blood flow to organs & leading to impairment of
physiology of organs. Later on, thrombus blocks the lumen completely so due to
complete loss of blood supply, cells damage occur.
CORONARY THROMBOSIS
Type of thrombosis when narrowing of lumen
occurs in coronary blood vessels due to formation of clot.
EFFECT
Occulsion of coronary atery causes myocardial
infarction and heart attack.
HEAMORRHAGE
The escaping of blood from intact blood vessels.
==STROKE Most dangerous type of heamorrhage is
that of brain which results in paralysis or strokes.
HAEMATOMA
The accumalation of blood in interstitial spaces
known as haematoma.
This will lead to edema.
STROKE
DEFINITION
The damage to the part of brain caused by,
restriction in blood supply or leakage of blood outside the vessels.
CHARACTERISTICS
Impairment of sensation, movement & function
controlled by damage part of brain.
CAUSES
* Hypertension
* Atherosclerosis
HEMIPLEGIA
Damage to any, one cerebral hemisphere can cause
weakness or paralyses of one side of body called hemiplegia
PRECAUTIONARY MEASURES
Blood pressure should be with in normal range
through proper diet. Salt should be used in less quantities exercise should be
the regular habit. Smoking must be avoided. Person life should be free of
worries.
BLOOD VESSELS
DEFINITION
"The closed vessels or tubes through which
transporting medium or blood circulate with in body called “blood vessels”.
TYPES OF BLOOD VESSELS
1. Arteries.
2. Capillaries.
3. Veins.
ARTERIES
DEFINITION
Thick walled blood vessels which carry blood
from heart to the organs of body.
LAYERS
It consists of three layers.
1. Tunica Externa/ Adventitia
2. Tunica Media
3. Tunica Intima
1-TUNICA EXTERNA
It is thin but tough layer, having abundant
amount of collagen fibers. It is outer most layer.
2-TUNICA MEDIA
The middle layer has smooth muscle fibers &
elastin fibers. It is the thickest layer.
3-TUNICA INTIMA
It consists of squamous endothelium.
LUMEN
Thick walled vessels & having smaller lumen
than that of veins except arteries of brain & related to cranium having
large lumen.
SEMILUNAR VALVES
They are not present in arteries.
BRANCHES - DIVISIONS
Aorta divides into large arteries, large
arteries into smaller arteries, smaller arteries into arterioles, then they
give rise to capillary.
At arteriole level, small sphincters are present
which are known as PRE-CAPILLARY SPHINCTER.
SPHINCTER
FUNCTION
They are for regulating the diastolic pressure.
CHARACTERSTICS
* Arteries are elastic so during systolic
pressure, they do not rupture and dilate.
* During ceasement/ stopage of systolic pressure
of heart, arteries contract & supply even flow of blood.
* The arteries carry oxygenated blood except
pulmonary arteries.
VEINS
DEFINITION
The thin walled blood vessels that drian blood
from body parts/organs into heart called veins.
LAYERS
* Tunica Externa
* Tunica Media
* Tunica Intima
1. TUNICA EXTERNA
Thickest layer in veins. It contains collagen,
elastin and smooth muscles cells.
2. TUNICA MEDIA
Not thicker as that of arteries. Elastic tissues
and small smooth muscle.
3. TUNICA INTIMA
Contains endothelial cells layer.
LUMEN
It has large lumen and thin wall.
SEMILUNAR VALVES
They are present in veins to prevent back flow
of blood in the influence of gravity.
TRIBUTARIES
Veninules -> small veins -> large veins
-> vena cava.
BLOOD PRESSURE
In veins blood pressure is low and are non
pulsatile.
CHARACTERISTICS
The blood flows slowly and smoothly in veins.
Veins are superficial and collapse when empty.
CAPILARIES
The intimate microscopic closed channels of both
arterial & veinous interconnected network is called capillaries.
DIAMETER
Capillaries are extremely narrow in diameter of
about 7-10 μ.
LAYERS
Capillaries are thin walled vessels &
contains single layer of endothelium which offers small resistance in transport
of material across the capillary wall.
FUNCTION
Through diffusion and active transport of oxygen
is transported to tissues & CO2 to capillaries. Nitrogenous waste is
filtered through the capillaries into excretory tubules.
BLUE BABIES (CYANOSIS)
Blue baby is a layman terminology. In medical
science it is known as cyanosis.
DEFINITION
The term cyanosis” means the blueish
discolouration of the skin & mucous membrane due to excessive cone of
reduced (deoxygenated haemoglobin) in the blood & it appears when reduced
Hb conc in capillaries is more than 5 gm/dl of blood. The reduced Hb has an
intense dark blue purple colour that is transmitted through the skin.
MOST COMMON CAUSE OF CYANOSIS
Although there are various other causes of
cyanosis but the most common cause is CONGENITAL CYANOTIC HEART DISEASE.
BASIC CAUSE OF CYANOSIS
In congenital heart diseases, there is an
abnormal connection b/w right and left side of heart, which permits the large
amount of unoxygenated venous blood to bypass the pulmonary capillaries &
dilute the oxygenated blood in systemic arteries i.e RIGHT TO LEFT SHUNT, which
results in cyanosis.
SOME EXAPLES OF CONGENITAL HEART DISEASES
* Some congenital heart diseases which are
responsible for the abnormal connection between right and left sides of heart
are as follows.
* ATRIAL SEPTUM DEFECT (ASD)
* VENTRICULAR SETPUM DEFECT (VSD)
* PERSISTANT DUCTUS ARTEROSUS
* In all these conditions, blood begins to flow
from the aorta (left side) into pulmonary arteries (right side) & the
people donot show cyanosis until late in life when heart fails or lungs become
congested.
TETRALOGY OF FALLOT (RIGHT –TO-LEFT SHUNT)
It is the most common cause of cyanosis or blue
baby in which aorta originates from right ventricles rather than left &
receives deoxygenated blood.
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Lymphatic System
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DEFINITION
A System of blind vessels (lymphatic) that
drains lymph from all over the body back into blood stream is called lymphatic
system OR Lymphatic System is essentially a drainage system, which reinforces
the venous drainage. There is no circulation i.e it is a unidirectional flow
towards heart.
MAIN FUNCTION OF LYMPHATIC SYSTEM
All body tissues are bathed in a watery fluid
derived from the blood stream. This intercellular or tissue fluid is formed
when blood passes trough the capillaries. The capillary walls are permeable to
all components of blood except the R.B.C’s & blood proteins. The fluid
passes from the capillary into the intercellular spaces as the inter-cellular
or tissue fluid. About 85% of the tissue fluid returns into the blood at the
venous end of capillary. The rest 15 % of tissue fluid drains into lymphatic
capillaries as lymph along with W.B.C’s, cell debris & micro organism like
Bacteria , are transported back to the heart through lymphatic system.
COMPONENTS OF LYMPHATIC SYSTEM
Lymphatic System Consists of
1. Lymph
2. Lymphatic tissues
3. Lymphatic vessels or Lymphatics
4. Lymph nodes (type of lymphatic tissue)
DETAILS OF COMPONENTS
1. LYMPH
DEFINITION
“Lymph is the name given to the tissue fluid once it has entered a
lymphatic vessel. OR It can be
defined as “Colour less body fluid that contains lymphocytes (agranular WBC’S),
small proteins & fats”.
EXPLANATION
Lymph is a medium of exchange between blood
& body cells. It takes the fluid substances from cell of tissues &
intercellular spaces, which cannot penetrate the blood capillaries.
2.LYMPHATIC TISSUES
DEFINITION
“Lymphatic tissues are a type of connective tissues that contain large
no. of lymphocytes”
ORGANS THAT CONTAIN LYMPHATIC TISSUES
Lymphatic tissue is organized into following
structures (organs).
- Lymph nodes
- Thymus
- Spleen
- Tonsils
- Some of the patches of tissues in vermiform appendix
& in small intestine.
FUNCTION
Lymphatic tissue is essential for immunologic
defenses of the body against viruses & bacteria.
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3. LYMPHATICS
DEFINITION
Lymphatic vessels or lymphatics are blind tubes
that assist the cardiovascular system in removal of tissue fluid from tissues
spaces of the body, the vessels then return the fluid to the blood.
AREAS WHERE LYMPHATIC ARE NOT PRESENT:
Lymphatics are present in all tissues &
organs of the body except.
- Central Nervous System
- The eye ball
- Internal Ear
- Epidermis of Skin
- Cartilage & bone
TYPES
Two Types of Lymphatics are there:-
SMALL - LYMPH CAPILLARIES
LARGE - LYMPH VESSELS.
1. LYMPH CAPILLARIES
DEFINITION
“Lymph capillaries are a network of thin walled,
anastomosing, microscopic vessels which are closed towards the tissue sinuses
& drain the Lymph from tissues."
2. LYMPH VESSELS
DEFINATION
The capillaries are in turn drained by lymph
tubes having larger diameters & beaded appearance, called the Lymph
vessels.
These vessels contain smooth muscles in them as
well as Internal valves to prevent the back flow of Lymph. The Lymph circulates
through the Lymph vessels by the contraction of surrounding skeletal muscles in
one direction (towards the heart). These vessels converge into collecting ducts
i.e right
Lymphatic duct & thoracic duct that drain
into large veins at the root of neck.
4. LYMPH NODES
DEFINITION
“Lymph nodes are lymphoid tissue which are present through out the course
of Lymphatics, through which the lymph must passes”
INTERNAL STRUCTURE
Each node consists of a thin, fibrous, outer
capsule & an inner mass of lymphoid tissue.
AFFERENT VESSELS
Several small Lymphatics which carry the lymph
into the lymph node are referred to as “Afferent vessels.”
EFFERENT VESSEL
A single large vessel which carry the lymph away
from the node is called “Efferent vessel”
FUNCTION
Lymph nodes act as filters that trap the
microorganisms & other foreign bodies in the lymph. The Lymphocytes &
macro-phages present here, neutralize & engulf the microorganisms,
respectively.
MAJOR FUNCTIONS OF LYMPHATIC SYSTEM.
From Text Book Pg. 379.
EDEMA
DEFINITION
“Whenever the tissue fluid accumulates rather than being drained into the
blood by the lymphatic system, tissue & body cavities become swollen. This
condition is known as “Edema”.
TYPES OF EDEMA
There are two types of Edema.
1. INTRACELLULAR
2. EXTRACELLULAR
1. INTRACELLULAR EDEMA
“Accumulation of excess of fluid within the
cells causing cellular swelling is called “Intra cellular Edema. It usually
occurs after severe extracellular Edema.
2. EXTRACELLULAR EDEMA
"Excess fluid accumulation in extra
cellular spaces is called Extracellular Edema. "
It is the most commonly occurring form of Edema.
FACTORS CAUSING EDEMA
Any factor that increases the tissue fluid high
enough than normal value can cause excess tissue fluid volume causing edema.
Some of these factor are as follows.
- High blood pressure
- Kidney failure
- Hart failure & etc.
CAUSES OF EDEMA
Following are three main causes of Edema.
1. HYPOPROTEINEMIA (SEVERE DIETARY PROTEIN DEFICIENCY)
When body is starving for Amino acids, it
consumes its own blood proteins. This reduces the osmotic potential of the
blood causing tissue fluid to accumulate in body tissues rather than being
drawn back into capillaries, resulting in Edema.
2. LYMPHATIC OBSTRUCITON (COMMONEST CAUSE –FILARIASIS )
Another cause of edema is lymphatic obstruction,
which results in more & more protein collection in the local tissue fluid
hence, the increased volume. Commonest cause of lymphatic obstruction is
FILARIASIS (infection by NEMOTODES) such condition is also called as
“Elephantiasis” (because of swollen legs).
3. INCREASED PERMEABILITY OF CAPILLARIES (CAUSES-BURNS & ALLERGIC
REACTIONS)
Sometimes the permeability of capillaries
increase due to burns or allergic reactions, so blood proteins & plasma
come out of capillaries & enter the tissue fluid thus causing Edema.
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Immune
System
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IMMUNITY
DEFINITION
“The ability of human body to resist almost all
types of micro-organisms, their toxins if any, foreign cells & abnormal
cells of the body is termed as “Immunity”
IMMUNOLOGY
DEFINITION
“The study of functioning & disorders of
Immune system is termed as “Immunology”.
IMMUNE SYSTEM
Immunity is conferred to animals through the
activities of the Immune System, which combats infectious agents.
DEFINITION
“Immune System is a collection of cells &
proteins that work to protect the body from potentially harmful, infectious
micro-organisms”
MAIN FUNCTIONS OF IMMUNE SYSTEM
Protection of body from all types of micro
organisms & toxins that tend to damage the tissues and organs of body.
ADDITIONAL FUNCTIONS
Immune system also play important role in:
* Control of cancer
* Allergy
* Hypersensitivity
* Rejection problems when organs or tissues are
transplanted.
DIVISIONS OF IMMUNE SYSTEM
* Immune system can be divided into two
functional divisions:
1. Innate Immunity System
2. Acquired Immunity System
INNATE IMMUNITY
DEFINITION
“The NON SPECIFIC type of immunity which result
from general processes , rather than from processes directed at specific
disease organism (Such as antigen –antibody reaction) is called. INNATE OR
NATURAL IMMUNITY & the system which is responsible for this type of
immunity is called Innate IMMUNITY System.
TYPES OF BARRIERS PROVIDED BY INNATE IMMUNITY
SYSTEM
* This system provides two types of barriers:
* Physical Barrier
* Chemical Barrier
PHYSICAL BARRIERS
* SKIN
* MUCOUS MEMBRANE & etc.
CHEMICAL BARRIERS
* Lysozyme
* Gastric juice (Acidic secretion of stomach)
& etc.
FIRST LINE OF DEFENCE
Skin, Mucous membrane & their secretions act
as “First line of Defence”
1. SKIN
The intact skin provides an impenetrable barrier
to the vast majority of infectious agents.
2. MUCOUS MEMBRANES
Most of the micro-organisms can enter only
through the mucous membranes that lines the digestive, respiratory &
urogenital tracts. However these areas are protected by movements of mucous
& secretions (e.g Lysozyme in tears) to destroy many microbs.
3. ACIDIC SECRETIONS
Most of he microorganisms present in food or
trapped in swallowed mucus from the upper respiratory tracts are destroyed by
highly acidic gastric juice of stomach.
SECOND LINE OF DEFENSE
If some how micro-organisms are able to
penetrate the outer layer of the skin or mucous membrance, they encounter a
second line of Defence offered by Innate Immunity system.
It is non specific & comprises of
1. PHAGOCYTES
2. ANTIMICROBIAL PROTEINS
3. INFLAMMATORY RESPONSE
1. PHAGOCYTES
Phagocytes are certain type of WBC’S which can
injest internalize & destroy the particles including infectious agents.
EXAMPLES OF PHAGOCYTIC CELLS
* NEUTROPHILS
* MACROPHAGES
NEUTROPHILS
Neutrophils (Polymorphonuclear Neutrophiles are
short lived phagocytic cells which can ingest the bacteria or any foreign
matter very actively.
MACROPHAGES (BIG EATERS)
The other phagocytic cells, the MONOCYTE can
develop into large LONG-LIVED MACRO PHAGES when they reside in various tissues
of body. ALSO CALLED AS ANTIGEN PRESENTING CELLS.
* Macrophages not only destroy individual micro
organisms but also play a crucial rule in further immune response by
“Presenting” parts of that microorganisms to other cells of immune system. For
this reason, they are termed as “ANTIGEN PRESENTING CELLS.
NATURAL KILLER (NK ) CELLS
Natural killer cells (NK Cells ) are the large
lymphocytes, which destroy the
* Virally infected own cells of the body
* Foreign cells
* Abnormal cells (cancerous cells)
MECHANISM OF ACTION (CYTOTOXICITY)
NK cells do not phagocytize the target cells,
instead, they bind to their target cells, release some PORE FORMING PROTEINS
(PERFORINS), that literally punch large round holes in the membrane of attacked
cells & eventually cause lysis of the target cells. This kind of destroying
the target cells is called “CYTOTOXICITY”
2. ANTIMICROBIAL PROTEINS
EXAMPLES
* Important antimicrobial proteins are:
* Lysozyme
* Compliment proteins
* Interferon
LYSOZYMES
Lysozyme, is a mucolytic polysaccharide that
causes the LYSIS OF BACTERIA it is present in TEARS, SALIVA, & MUCUS
SECRETION.
COMPLEMENT PROTEINS
Complement is a collective terms that describes
a system of about 20 PROTEINS, many of which are INACTIVE ENZYME PRECURSORS.
The principal actors in this system are 11 Proteins. All these proteins are
present among the Plasma Proteins.
ACTIVATION OF COMPLIMENT PROTEINS
These proteins can be activated by two ways.
* CLASSICAL PATH WAY-Act in Adaptive Immunity
system.
* ALTERNATIVE PATH WAY- Act in Innate Immunity
System.
FUNCTIONS
Main functions of compliment proteins are as
follows:
1. DIRECT LYSIS OF BACTERIA
2. PROMOTE THE PHAGOCYTOSIS OF BACTERIA
3. NEUTRILIZATION OF VIRUSES
4. CHEMOATTRACTANTS FOR MACROPHAGES.
INTERFERONS (ANTIVIRAL AGENTS)
Interferon are secreted by virally infected
cells or some lymphocytes to induce a state of ANTI VIRAL RESISTANCE in
unaffected tissues of the body.
3. INFLAMMATION
Inflammation is the body’s reaction to an injury
or by entry of micro organisms.
EFFECTS OF INFLAMMATION
A cascade of chemical reactions take place
during inflammatory response.
1. When injured, BASOPHILS and MAST CELLS
release a substance called HISTAMINE which causes.
* Increased permeability of adjacent
capillaries.
* Local vasodilatation
* Increased leakage of capillaries.
2. Due to CHEMOTAXIS, Phagocytes &
macrophages are attracted at the injured site. Thus Phagocytes literally eat up
microorganisms, dirt, cell debris & etc forming pus.
SYMPTOMS
Redness, heat, swelling, pain in injured tissue.
FEVER -(ALSO CONTRIBUTES TO DEFENSE OF BODY)
In case of warm blooded animals, a no. of micro
organisms who escape away from inflammatory response to infect some large part
of the body, trigger FEVER. It is usually caused by WBC’S, that release the
substance called as PYROGEN.
FUNCTIONS
* High fever is dangerous but moderate fever
contributes to the defense of the body.
* It inhibits the growth of micro-organisms.
* May speed up the repair of damaged tissues.
* Facilitates the phagocytosis, increase the
production of interferons.
ADAPTIVE IMMUNE SYSTEM
DEFINITION
“The specific type of Immunity which does not
develop until after the body is first attacked by a bacterial disease or a
toxin, is called “Adaptive or Acquired Immunity”. The system which provides
this type of immunity is called “ADAPTIVE or ACQUIRED IMMUNE SYSTEM”
OR
“Acquired Immunity is provided by special Immune
System that form Antibodies & activated lymphocytes that attack &
destroy the specific organisms or toxins. This is the THIRD LINE OF DEFENCE.
DEVELOPMENT OF IMMUNE SYSTEM (LYMPHOCYTES ARE
THE BASIS OF ADAPTIVE IMMUNE SYSTEM)
Acquired Immune system is actually the product
of body’s Lymphocytic system. The responses of adaptive Immune system is
provided by Lymphocytes.
TYPES OF LYMPHOCYTES
During fetal development, all lymphocytes come
from Bone Marrow. But depending upon their migration & maturity, they can
be divided into two populations.
1. “T” - Cells or “T” LYMPHOCYTES
2. “B” - Cells or “B” LYMPHOCYTES.
1. “T” LYMPHOCYTES
DEFINITION
“The lymphocytes that are destined to eventually
form ACTIVATED “T” LYMPOCYTES first migrate to & then mature in THYMUS
GLAND, that is why, they are called as “T” LYMPHOCYTES”
FUNCTIONS
These are responsible for “CELL-MEDIATED
IMMUNITY
2. “B” LYMPHOCYTES
DEFINITION
“The lymphocytes that are destined to form
ANTIBODIES are processed first in the LIVER (before birth) & then in BONE
MARROW (after the birth). This population of cells was first discovered in
birds where processing occurs in BURSA OF FABRICIUS (not found in mammals),
hence they are called as “B” LYMPHOCYTES.”
FUNCTIONS
These are responsible for HUMORAL IMMUNITY
ADAPTIVE IMMUNE SYSTEM IS INITIATED BY ANTIGENS
In order to develop a specific immune response,
the immune system must recognize the invading organisms and / or foreign
proteins from its self tissues & proteins.
ANTIGEN
Any foreign substance, that elicit the immune
response is called antigen. In general Antigens are proteins or large
polysaccharides.
RESPONSE OF IMMUNE SYSTEM TO ANTIGEN
The immune system responds to an antigen by
ACTIVATING LYMPHOCYTES & PRODUCING ANTIBODIES (Soluble Proteins). The
antibody combines with antigen & helps to eliminate it from the body.
BASIC TYPES OF ADAPTIVE IMMUNITY
The adaptive immune system mounts two types of
attacks on invading micro-organisms.
1. HUMORAL IMMUNITY
2. CELL MEDIATED IMMUNITY (CMI)
1. HUMORAL IMMUNITY
DEFINITION
“The immunity which is mediated by circulating
antibodies produced by B-lymphocytes is called “ HUMORAL IMMUNITY”.
MAJOR FUCTIONS OF HUMORAL IMMUNITY
Humoral Immunity provides major defence against
“BACTERIAL INFECTIONS
MECHANISM OF ACTION OF B CELLS
“B” CELL RECEPTORS
Each B-cell has specific type of antibodies on
its cell surface. This antibody serves as ANTIGENIC RECEPTOR.
ACTIVATION OF SPECIFIC “B” CELLS
On entry of foreign antigen, those B cells
specific for that antigen enlarge immediately, becomes activated & form two
types of cells:
1. PLASMA CELLS
2. MEMORY CELLS
1. PLASMA CELLS
The activated B-cells proliferate rapidly &
transform into enlarged effectors cells called plasma cells.
FUNCTION
Plasma cells secrete ANTIBODIES into the
circulation that help to eliminate that particular antigen.
ACTIONS OF ANTIBODIES.
After the formation of antigen-antibody complex
antibody can inactivate the invading agent in one of the several ways.
* By activation of complement system that cause
the Lysis.
* Direct Phagocytosis.
* Neutralization of the toxins released by
bacteria.
* Agglutination of microorganism.
2. MEMORY CELLS
DEFINITION
Some of the activated B-cells don’t go on to
form the plasma cells but instead, form moderate number of new B-cells, which
don’t secrete antibodies such cells are called as Memory cells.
FUNCTIONS
The memory cells play important role in future
immunity to this specific organism in case of re-infection.
2. CELL MEDIATED IMMUNITY (CMI)
DEFINITION
The second type of acquired immunity is achieved
through the formation of large number of Activated LYMPHOCYTES. This is called
cell mediated or T-cell immunity.
FUNCTIONS OF CMI
* CMI is responsible for delayed allergic
reactions & rejection of transplantation of foreign tissue.
* It provides major defence against infections
due to VIRUSES, FUNGI, TUBERCLE BACILLI & some parasites.
* It also provides defence against TUMOUR CELLS.
MECHANISM OF ACTION OF “T”-CELLS.
T-CELL RECEPTORS (TCRS)
Antigens bind with specific RECEPTOR MOLECULES
on the surface of T-Cells, in the same way that they bind the antibodies.
ACTIVATION OF SPECIFIC “T” CELLS.
On exposure to proper antigen, the “T” cells of
specific type proliferate & release large no. of activated T-Cells.
SEVERAL TYPES OF “T” CELLS
Different types of T cells are classified into
four major groups.
* HELPER “T” CELLS
* CYTOTOXIC “T” CELLS
* SUPRESSER “T” CELLS
* MEMORY “T” CELLS
1. HELPER “T” CELLS
Helper T cells are the MAJOR REGULATOR of all
the immune functions.
RECEPTORS
Helper T cell receptors actually recognize a
combination of antigen fragment & one of the body’s own self marker called.
“MAJOR HISTO-COMPATIBILITY” (MHC) CLASS II molecules on the surface of
macrophages or B cells.
FUNCTIONS
Helper T-cells secrete the LYMPHOKINES which
stimulate the production of both CYTOTOXIC & SUPRESSER TOXINS.
2. CYTOTOXIC “T” CELLS (KILLER CELLS)
RECEPTORS
Receptors on the surface of cytotoxic ‘T” cells
recognize a combination of antigen fragment & self surface marker molecules
called MHC CLASS I , found on every nucleated cells of its own body.
FUNCTIONS
They are especially lethal to virally infected
cells. They also destroy the cancer cells, heart transplant cells & other
foreign cells.
3. SUPRESSOR “T” CELLS
Along with helper cells, In supressor, T-cells
are classified as Regulatory T-Cells
FUNCTIONS
After the conquerence of infection, they seems
to shut off the immune response in both B-cells & cytotoxic T-cells.
4. MEMORY “T” CELLS
During CMI response, some T-cells turn into
MEMORY CELLS
FUNCTION
Memory cells protect the body in case of
reaction in future.
TYPES OF IMMUNE RESPONSE
The immune system has also the ability to
memorize the antigen it has encountered. Thus upon subsequent exposure to the
same pathogen responds in two different ways.
1. Primary Immune Response
2. Secondary Immune Response
1. PRIMARY IMMUNE RESPONSE
DEFINITION
The first exposure to an antigen to the immune
system elicits formation of clones of effectors cells to develop specific
immunity with in 5 to 10 days. This response of immune system is termed as
Primary Immune response.
CHARACTERISTICS
* DELAYED APPEARANCE
* WEAK POTENCY
* SHORT LIFE
2. SECONDARY IMMUNE RESPONSE
DEFINITION
Subsequent exposure of same antigen causes a
much more rapid & much more potent antibody response. This is called
Secondary Immune response. It develops to it max. with in 3-5 days.
CHARACTERISTICS
* Rapid & quicker appearance
* Far more potent
* Longer duration (form antibodies for many
months rather than for only a few weeks.)
BASIS OF SECONDARY RESPONSE (IMMUNOLOGICAL
MEMORY)
The quicker secondary response is made possible
due to ability called “Immunological Memory” of the immune system. It is based
upon the long lasting memory cells produced with short lived effectors cells of
pri immune response. The development of memory cells may provide life long protection
against some diseases like chicken pox.
ACTIVE & PASSIVE IMMUNITY
ACTIVE IMMUNITY
DEFINITION
The immunity which is acquired by own immune
response is called active immunity
FUNCTION OF ACTIVE IMMUNITY
Active immunity due to development of immunological
memory provide LONG TERM PROTECTION, even in some diseases (e.g in chicken Pox
) life long protection is provided.
TYPES OF ACTIVE IMMUNITY
There are two types.
1. Natural active immunity
2. Artificial active Immunity
1. NATURAL ACTIVE IMMUNITY
DEFINITION
When the active immunity is acquired as a
consequence of natural infection then it is called Natural active immunity”
2. ARTIFICIAL ACTIVE IMMUNITY
DEFINITION
Active immunity can be acquired artificially by
vaccination. In this case it is said to be “ARTIFICIAL ACTIVE IMMUNITY”
PASSIVE IMMUNITY
DEFINITION
Temporary immunity which is achieved in a person
without injecting an antigen, by transferring the antibodies, activated T-cells
or both obtain from another person or even an animal, is called passive
immunity.
FUNCTIONS OF PASSIVE IMMUNITY
Although, acquired passive immunity is short
lived (last for 2-3 weeks), it boosts the immune response of the victim several
folds.
TYPES OF PASSIVE IMMUNITY
There are 2 Types:
1. Natural passive Immunity
2. Artificial passive Immunity
1. NATURAL PASSIVE IMMUNITY
DEFINITION
When antibodies are transferred from one person
to another of the same species during natural processes, then such immunity is
called Natural passive immunity.
EXAMPLE
A pregnant woman passes some of the antibodies
to her fetus through placenta. The first breast feeding, the colostrum, of
mother pass certain antibodies to her newly born infant.
2. ARTIFICIAL PASSIVE IMMUNITY
DEFINITION
PASSIVE IMMUNITY can also be transferred
artificially by introducing antibodies derived from animals or human being who
are already actively immunized to that disease. This is called artificial
passive immunity.
EXAMPLE
RABIES is treated in man by injecting antibodies
derided from persons who have been already vaccinated against rabies. This
confers the rapid immunity to combat the rapidly progressing rabies in new
victim.
IMMUNIZATION
The process of inducing immunity as a preventive
measure against certain infectious diseases is called immunization.
ADVANTAGES OF IMMUNIZATION
The incidence of number of diseases (e.g
Diptheria, Measles) has declined dramatically since the introduction of
effective immunization programmers. Some dread full diseases (e.g. Tuberculosis)
is now under control.
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