ZOOLOGY
, Contents
UNIT I : Diversity of Living World 1-28
1.1 What is Life? 3
1.2 Nature, Scope and Meaning of Zoology 6
1.3 Branches of Zoology 6
1.4 Need for Classification 8
1.5 Biological Classification 8
1.6 Levels and Hierarchy of Classification 9
1.7 Nomenclature 11
1.8 Species Concept 12
1.9 KingdomAnimalia 13
1.10 Biodiversity 16
UNIT II: Structural Organization in Animals 29-62
2.1 Levels of Organization 31
2.2 Importance of Symmetry 34
2.3 Coelom 36
2.4 Animal Tissues 40
UNIT III: Animal Diversity - I (Invertebrate Phyla) 63-92
3.1 Phylum - Porifera 65
3.2 Phylum - Cnidaria 66
3.3 Phylum - Ctenophora 68
3.4 Phylum - Platyhelminthes 69
3.5 Phylum - Nematoda 71
3.6 Phylum - Annelida 72
3.7 Phylum - Arthropoda 79
3.8 Phylum - Molusca 82
3.9 Phylum - Echinodermata 85
3.10 Phylum - Hemichordata 87
UNIT IV: Animal Diversity - II (Chordata Phylum) 93-124
4.1 Phylum - Chordata 95
4.2 Subphylum - Cephalochordata 98
4.3 Subphylum - Vertebrata/Craniata 98
, 4.4 Super Class : Agnatha 99
4.5 Super Class : Gnathostomata 99
4.6 Tetrapoda 103
UNIT V: Locomotion and Reproduction 125-140
5.1 Locomotion in Protozoa 127
5.2 Flagellar and Ciliary movement 132
5.3 Asexual Reproduction 135
5.4 Sexual Reproduction 138
UNIT VI: Biology in Human Welfare 141-174
6.1 Parasitism and Parasitic adaptations 143
6.2 Health and Disease 147
6.3 Brief Account of some other Diseases 163
6.4 Tobacco, Drugs and Alcohol abuse (TDAAbuse) 165
UNIT VII: Periplaneta americana (Cockroach) 175-202
7.1 Habitat and Habit 176
7.2 External Features (Morphology) 176
7.3 Locomotion 181
7.4 Digestive System 181
7.5 Circulatory System 184
7.6 Respiratory System 187
7.7 Excretory System 189
7.8 Nervous System and Sense organs 191
7.9 Reproductive System 195
UNIT VIII: Ecology and Environment 203-269
8.1 Organisms and Environment 206
8.2 Ecosystem - ElementaryAspects 209
8.3 Population Interactions 220
8.4 Ecosystems and Their Components 228
8.5 Food Chains, Food Web, Productivity and Energy Flow 230
8.6 Nutrient Cycles 238
8.7 Population 241
8.8 Environmental Issues 246
References 270
Model Question Paper 274
, Unit
Diversity of Living World 1
Charles Darwin, a British Naturalist,
went round the world in the ship called
H.M.S. Beagle, for five years. He
1
published his findings in his book -
ORIGIN OF SPECIES. According to him
evolution involves ‘descent with
modification’. With no reservations,
one can call him - THE BIOLOGIST OF
THE NINETEENTH CENTURY.
Diversity of Living World
Biology is the science of life and living processes. The living world comprises
an amazing diversity of living organisms. However, living organisms show
‘Fundamental Similarity’ in many respects. The study of ‘Life’ involves a
multidisciplinary approach, involving many of the principles of chemistry, physics
and mathematics too at some places. Biological systems are the most ‘complex
chemical systems’ on the Earth. The bodies of early organisms are at the ‘cellular’
level. However large an organism is, ‘cells’ of an organism are the ‘Basic Units’ of
‘structure’ and ‘function’. Organisms constantly interact with their surrounding
environment ‘exchanging energy’ and ‘recycling minerals’. The intricate chemical
processes of cells are based on the basic principles of chemistry. Every level of
biological organisation involves ‘energy transactions’ governed by the ‘Laws of
thermodynamics’. The fundamental source of energy for all biological systems is
the ‘Sun’. Green plants, over a period of several millions of years, evolved and have
mastered the art of converting solar energy into chemical energy involving complex
reactions and pass it on to other higher living organisms to keep LIFE going.
Life defies simple definition although one can easily perceive the difference
between inanimate matter (wind, sea, fire, etc.) and ‘living organisms’. Cellular
organisation, ordered complexity, ability to reproduce themselves, showing growth,
utilisation and transfer of energy, maintaining constancy in the internal
environment (in spite of variations in the surrounding environment), irritability
(showing sensitivity to stimuli) and above all, exhibiting the ability to adapt and
evolve (change from simple structure to complex) are some of the ‘traits’ of life and
living organisms. Diversity in living organisms comes from their ability to ‘change’.
The process of evolution is continuous and newer forms evolve continuously (Descent
with Modification), while some perish in the struggle for existence, as envisaged by
Charles Darwin. Evolution is the ‘Fundamental Organising Principle’ of life and it
answers many questions about life and its complexity - a scientific explanation for
‘unity’ and ‘diversity’.
, Contents
UNIT I : Diversity of Living World 1-28
1.1 What is Life? 3
1.2 Nature, Scope and Meaning of Zoology 6
1.3 Branches of Zoology 6
1.4 Need for Classification 8
1.5 Biological Classification 8
1.6 Levels and Hierarchy of Classification 9
1.7 Nomenclature 11
1.8 Species Concept 12
1.9 KingdomAnimalia 13
1.10 Biodiversity 16
UNIT II: Structural Organization in Animals 29-62
2.1 Levels of Organization 31
2.2 Importance of Symmetry 34
2.3 Coelom 36
2.4 Animal Tissues 40
UNIT III: Animal Diversity - I (Invertebrate Phyla) 63-92
3.1 Phylum - Porifera 65
3.2 Phylum - Cnidaria 66
3.3 Phylum - Ctenophora 68
3.4 Phylum - Platyhelminthes 69
3.5 Phylum - Nematoda 71
3.6 Phylum - Annelida 72
3.7 Phylum - Arthropoda 79
3.8 Phylum - Molusca 82
3.9 Phylum - Echinodermata 85
3.10 Phylum - Hemichordata 87
UNIT IV: Animal Diversity - II (Chordata Phylum) 93-124
4.1 Phylum - Chordata 95
4.2 Subphylum - Cephalochordata 98
4.3 Subphylum - Vertebrata/Craniata 98
, 4.4 Super Class : Agnatha 99
4.5 Super Class : Gnathostomata 99
4.6 Tetrapoda 103
UNIT V: Locomotion and Reproduction 125-140
5.1 Locomotion in Protozoa 127
5.2 Flagellar and Ciliary movement 132
5.3 Asexual Reproduction 135
5.4 Sexual Reproduction 138
UNIT VI: Biology in Human Welfare 141-174
6.1 Parasitism and Parasitic adaptations 143
6.2 Health and Disease 147
6.3 Brief Account of some other Diseases 163
6.4 Tobacco, Drugs and Alcohol abuse (TDAAbuse) 165
UNIT VII: Periplaneta americana (Cockroach) 175-202
7.1 Habitat and Habit 176
7.2 External Features (Morphology) 176
7.3 Locomotion 181
7.4 Digestive System 181
7.5 Circulatory System 184
7.6 Respiratory System 187
7.7 Excretory System 189
7.8 Nervous System and Sense organs 191
7.9 Reproductive System 195
UNIT VIII: Ecology and Environment 203-269
8.1 Organisms and Environment 206
8.2 Ecosystem - ElementaryAspects 209
8.3 Population Interactions 220
8.4 Ecosystems and Their Components 228
8.5 Food Chains, Food Web, Productivity and Energy Flow 230
8.6 Nutrient Cycles 238
8.7 Population 241
8.8 Environmental Issues 246
References 270
Model Question Paper 274
, Unit
Diversity of Living World 1
Charles Darwin, a British Naturalist,
went round the world in the ship called
H.M.S. Beagle, for five years. He
1
published his findings in his book -
ORIGIN OF SPECIES. According to him
evolution involves ‘descent with
modification’. With no reservations,
one can call him - THE BIOLOGIST OF
THE NINETEENTH CENTURY.
Diversity of Living World
Biology is the science of life and living processes. The living world comprises
an amazing diversity of living organisms. However, living organisms show
‘Fundamental Similarity’ in many respects. The study of ‘Life’ involves a
multidisciplinary approach, involving many of the principles of chemistry, physics
and mathematics too at some places. Biological systems are the most ‘complex
chemical systems’ on the Earth. The bodies of early organisms are at the ‘cellular’
level. However large an organism is, ‘cells’ of an organism are the ‘Basic Units’ of
‘structure’ and ‘function’. Organisms constantly interact with their surrounding
environment ‘exchanging energy’ and ‘recycling minerals’. The intricate chemical
processes of cells are based on the basic principles of chemistry. Every level of
biological organisation involves ‘energy transactions’ governed by the ‘Laws of
thermodynamics’. The fundamental source of energy for all biological systems is
the ‘Sun’. Green plants, over a period of several millions of years, evolved and have
mastered the art of converting solar energy into chemical energy involving complex
reactions and pass it on to other higher living organisms to keep LIFE going.
Life defies simple definition although one can easily perceive the difference
between inanimate matter (wind, sea, fire, etc.) and ‘living organisms’. Cellular
organisation, ordered complexity, ability to reproduce themselves, showing growth,
utilisation and transfer of energy, maintaining constancy in the internal
environment (in spite of variations in the surrounding environment), irritability
(showing sensitivity to stimuli) and above all, exhibiting the ability to adapt and
evolve (change from simple structure to complex) are some of the ‘traits’ of life and
living organisms. Diversity in living organisms comes from their ability to ‘change’.
The process of evolution is continuous and newer forms evolve continuously (Descent
with Modification), while some perish in the struggle for existence, as envisaged by
Charles Darwin. Evolution is the ‘Fundamental Organising Principle’ of life and it
answers many questions about life and its complexity - a scientific explanation for
‘unity’ and ‘diversity’.
