Human Physiology / Nitin Ashok John

CC Chatterjee’s Human Physiology, Volume 1 CC Chatterjee’s Human Physiology, Volume 2

1. Cell Physiology: Structure and Functions
of Cell Organelle 2
Introduction 2
Cell Structure 2
Cell Membrane 2
Cytoplasm and its Organelles 4
Nucleus 6
Chromatin 7
Chromosomes 7
Applied Physiology 7
Intercellular Communication and Mode of
Communication 7
Special Structural Features of Cell and Intercellular
Communication 7
Molecular Motors 9
Apoptosis 9
Applied Physiology 9
Methods used to Demonstrate the Functions of the Cells
and its Product 10
Exam-oriented Questions 13
2. Homeostasis 14
Introduction 14
Role of Various Systems of Body in Homeostasis 14
Role of Neuroendocrine Reflex in Homeostasis 14
Feedback Homeostasis Regulations 15
Examples of Negative Feedback Mechanism 15
Examples of Positive Feedback Mechanism 16
Internal Factors Influencing Homeostasis 17
External Factors Influencing Homeostasis 17
Exam-oriented Questions 17
3. Transport Across Cell Membrane 18
Introduction 18
Introducing to Key Terms and Concepts 18
Important Concepts in Transport Mechanism 18
Ion Channels 18
Types of Transport Mechanism 19
Characteristic Features 21
Osmosis 21
Membrane Transport: Active Transport 22
Primary Active Transport 22
Secondary Active Transport 23
Vesicular Transport Mechanisms 25
Transport through Cellular Sheets 26
Applied Physiology 26
Exam-oriented Questions 26
4. Membrane Potential 27
Introduction 27
Role of Ion in Generating Membrane Potential 27
Ionic Mechanisms of Resting Potentials 27
Physico-chemical Principles Involved in Generating RMP 27
Nernst Potential 27
Goldman-Hodgkin and Katz (GHK) Equation 27
Gibbs-Donnan Membrane Equilibrium 27
Recording of Membrane Potential 28
Graded Potential and Action Potential 28
Introduction 28
Terms Associated with Membrane Potential 29
Graded Potential 29
Local Response of Graded Potential 29
Types of Graded Potential 29
Summation of Graded Potential 29
Action Potential 29
Characteristics of Action Potential 30
Nerve Stimulation and Phases of Action Potential 30
Ionic Basis of Action Potential 31
Cardiac Action Potentials 31
Property of Action Potential 32
Ion Channel Studies 33
Procedures 33
Exam-oriented Questions 33
5. Body Fluids and Blood Volume 34
Introduction 34
Total Body Water and its Distribution 34
Extracellular Fluid Compartment 34
Blood Volume 35
Methods of Determination of Blood Volume 35
Blood Volume 35
Measurement of Plasma Volume 35
Measurement of Interstitial Fluid Volume 35
Interstitial Fluid (IF) 35
Intracellular Fluid Compartment (ICF) 35
Measurement of Body Fluid Compartments 36
Total Body Water 36
Extracellular Fluid Volume 36
Intracellular Fluid Measurement 36
Hydrogen Ion Concentration of the Body Fluids 37
Regulation of Body Fluid Volume 37
Exogenous and Endogenous Water Input 37
Water Excretion and its Daily Output 37
Maintenance of Electrolyte Balance 37
Potassium Conc and its Balance 37
Disorders of Fluid Volume 38
Exam-oriented Questions 38
Clinical Case Scenario 39
General Physiology 39
Contents
Preface to the Fourteenth Edition v
Preface to the First Edition vi
Index of Competencies xix
viiiHuman Physiology
Section II Blood
6. Composition and Functions of Blood 42
Introduction 42
Properties of Blood 42
Composition of Blood 42
Functions of Blood 42
Relative Volume of Corpuscles and Plasma 43
Exam-oriented Questions 44
7. Specific Gravity of Blood 45
Introduction 45
Rise in Specific Gravity 45
Fall in Specific Gravity 45
Method of Determination 45
Exam-oriented Questions 45
8. Plasma Proteins 46
Introduction 46
Plasma Proteins Varieties 46
Origin of Plasma Proteins 46
Rate of Regeneration of Plasma Proteins: Whipple’s
Experiment 46
Whipple’s Experiment 46
Relation of Diet to Plasma Proteins 46
Functions of Plasma Protein 47
Exam-oriented Questions 47
9. Viscosity and Erythrocyte Sedimentation
Rate (ESR) 48
Introduction 48
Viscosity: Characteristics 48
Suspension Stability of Blood (Erythrocyte Sedimentation
Rate or ESR) 48
ESR Increased and Decreased 49
Significance of ESR 49
Physiological Variations in ESR 49
Exam-oriented Questions 49
10. Coagulation of Blood 50
Introduction 50
Importance of Coagulation of Blood 50
General Characteristics of Coagulation 50
Blood Coagulation Factors 51
Factor I or Fibrinogen 51
Factor II or Prothrombins 51
Factor III or Thromboplastin 51
Factor IV or Calcium 51
Factor V or Labile Factor Accelerator Globulin or
Proaccelerin 51
Factor VII or Stable Factor or Proconvertin 51
Factor VIII or Antihaemophilic Factor (AHF) or
Antihaemophilic Globulin (AHG) or Platelet
Cofactor I 51
Factor IX or Christmas Factor or Plasma Thromboplastin
Component (PTC) or Platelet Cofactor II 52
Factor X or Stuart Factor 52
Factor XI or Plasma Thromboplastin Antecedent
(PTA) 52
Factor XII or Hageman or Surface Factor 52
Factor XIII or Fibrin-stabilising or Laki-Lorand Factor
(LLF) 52
Fitzgerald Factor also known as High Molecular
Weight Kininogen 52
Fletcher Factor also known as Prekallikrein 52
Other Important Factors Participating in Coagulation
Mechanism 52
Thrombomodulin 52
Protein C 52
Protein S 52
Anti-thrombin III 52
Tissue Factor Pathway Inhibitor 52
Extrinsic and Intrinsic Mechanisms of Coagulation of
Blood 52
Clot Retraction 53
Fibrinolysis 54
Plasminogen 54
Natural Inhibitors of Coagulation 55
Antithrombin Activities Remove Thrombin from
Blood 55
Intravascular Clotting or Thrombosis 55
Thrombus 55
Heparin as an anticoagulant 55
Characteristics 55
Applied Physiology 55
Coagulation Disorders 55
Bleeding Disorders 56
Exam-oriented Questions 58
11. Bone Marrow 59
Introduction 59
Key Points 59
Red Bone Marrow 59
Yellow Bone Marrow 59
Vascular Arrangement in the Bone Marrow 59
Functions of Bone Marrow 59
Formed Elements of Blood 59
Precursors of Blood Cells 60
Applied Physiology: Bone Marrow Biopsy 62
Exam-oriented Questions 62
12. Red Blood Corpuscles (Erythrocytes) 63
Introduction 63
Size, Volume, Thickness, etc. of Red Blood
Corpuscles 63
Cytoplasm of the Red Cells 63
Normal Red Cell Count 63
Variations of Red Cell Count under Various Physiological
Conditions 63
Abnormal Forms of Erythrocytes 63
Stages of Blood Formation in the Embryo and Foetus 64
Site of Development 64
Important Factors Controlling Erythropoiesis 64
Maturation of Red Blood Cells 64
Stages of Development 64
Factors Regulating Erythropoiesis 66
Energy Metabolism of RBC 66
Key Points 66
Functions of Red Blood Corpuscles 68
Exam-oriented Questions 68
13. Haemoglobin 69
Introduction 69
Chemistry 69
Structure of Haemoglobin 69
Properties 70
Haemoglobin Varieties 70
Haemoglobin and its Variant 70
Synthesis of Haemoglobin 70
Amount of Haemoglobin in Normal Blood 70
Variations of Hb under Different Physiological
Conditions 71
Derivatives of Haemoglobin 71
Exam-oriented Questions 72
ixContents
14. Iron Absorption, Transport, Storage and
Excretion 73
Introduction 73
Daily Requirement 73
Distribution of Iron 73
Absorption and Transport 73
Key Points 73
Iron in Blood 73
Storage of Iron 73
Excretion 74
Functions of Iron 74
Applied: Iron Deficiency Anaemia 75
Exam-oriented Questions 75
15. Anaemia, Polycythemia, Osmotic
Fragility and Blood Indices 76
Introduction 76
Other Causes 76
Sickle Cell Anaemia 76
Thalassemia 76
Alpha Thalassemia 78
Beta Thalassemia 78
Glucose-6-Phosphate Dehydrogenase Deficiency 78
Congenital Spherocytosis 78
Blood Indices and Morphological Classification of
Anemia 78
Determination of Osmotic Fragility of Red Blood Cells 79
Principle 79
Procedure 79
Precautions 79
Applied Physiology: Haemolysis and Osmotic Fragility 79
Polycythemia 80
Exam-oriented Questions 80
16. White Blood Cells and Platelets 81
White Blood Cells 81
Variations in Normal Count of White Blood Corpuscles 81
Classification and Differential Count of White Blood
Corpuscles or Leucocytes 81
Granular Leucocytes or Granulocytes 82
Neutrophil 82
Arneth Count or Arneth Index (Modified by
von Bonsdorff and Later by Cooke) 82
Eosinophil (1–4%) 83
Basophil (0–1%) 83
Lymphocytes (20–40%) 83
Small Lymphocyte 83
Large Lymphocyte 83
Monocytes (Large Mononuclear Cell, Transitional
Cell, etc.) (2–8%) 84
Characteristic Features 84
Development of Leucocytes 84
Development of Granular Leucocytes or Granulocytes 84
Development of Lymphocytes 85
Role of Lymphocyte in Immunology 86
Development of Monocytes 86
Life and Fate of Leucocytes 86
Functions of WBC 86
Applied Physiology: WBC Disorders 86
Platelets 87
Properties 87
Total Number and its Variations 87
Methods of Counting of Platelets 88
Development of Platelets 88
Functions of Platelets 88
Exam-oriented Questions 89
17. Blood Groups and Blood Transfusion 90
Blood Groups 90
A, B and O Groups 90
Rh Antibodies and Rh Incompatibility 91
Erythroblastosis Foetalis 91
M and N Factors: Medicolegal Significance 91
H Blood Group System and Bombay Phenotype 92
Blood Transfusion: Blood Groups 92
Indications for Blood Transfusion 92
Autologous Transfusion 92
Mismatched Blood Transfusion 93
Blood Bank 93
Blood Storage 93
Exam-oriented Questions 93
18. Formation of Tissue Fluids 94
Introduction 94
Composition of Tissue Fluid 94
Functions of Tissue Fluid 94
Oedema and its Causes 95
Aggregation of Tissue Fluid 95
Lymph and Lymphatics 95
Characteristic Features 95
Properties of Lymph 95
Composition of Lymph 95
Solids 95
Rate of Flow 95
Factors Responsible for Formation of Lymph 97
Functions of Lymph 98
Lymph Node 98
Structure of Lymph Node 98
Functions of Lymph Node 99
Structure of Spleen 99
Splenic Pulp 99
Marginal Zone 100
Functions of Spleen 101
Classification, Varieties and Distribution of RE Cells 102
Functions of the Reticuloendothelial System 103
Exam-oriented Questions 103
19. Immunity 104
Introduction 104
Innate Defenses 104
Complement 105
Adaptive Defenses 106
Development of the Acquired Immune System 106
Humoral Immunity 107
Acquired Humoral Response: Formation of Primary and
Secondary Antibodies 107
Types of Acquired Immunity 107
Antibody Mediated Humoral Response 108
Cell-mediated Immune Response 108
T Cell Activation 109
Function of T Helper Cells, Cytotoxic T Cells and
Suppressor T Cells 109
Organ Transplant 110
Severe Combined Immunodeficiency (SCID)
Syndrome 110
Acquired Immune Deficiency Syndrome (AIDS) 110
Hypersensitivity 110
Exam-oriented Questions 111
Clinical Case Scenario 112
Blood 112
Recent Advances: Innate Immunity 113
x Human Physiology
2008 Nobel Prize for Physiology and Medicine: HIV
Virus 114
Notable Contributions: Diseases, Drugs, Immunity and
Recovery 114
Section III Nerve and Muscle
20. Structure and Functions of Neuron 118
Introduction 118
Histological Structure 118
Neuron 118
Structure of Nerve Fibres 118
Neuroglia 120
Functions of Neuroglia 120
Axonal Transport and Nourishment of Neurons 121
Role of Neurotrophins in Neuronal Development 121
Exam-oriented Questions 121
21. Properties, Classification of Nerve
Fibres and Nerve Action Potential 122
Introduction: Properties of Nerve Fibres 122
Excitability 122
Generation of Action Potential and Excitability
of the Nerve 122
Ionic Basis of Excitability of Nerve 122
Excitability Depends upon Following Factors 124
Compound Action Potential 124
Conductivity 124
Factors Affecting Conductivity and Excitability 125
All-or-none Law 126
Refractory Period 126
Summation 126
Adaptation 126
Accommodation 126
Unfatigability 126
Heat Production in Nerve Fibre 126
Classification of Nerve Fibres 127
Mechanism of Conduction of the Nerve Impulse 127
Saltatory Conduction in the Myelinated
Nerve Fibre 128
Physiological Properties of the Nerve Fibres 129
Degeneration and Regeneration of Nerve 129
Sunderland Classification of Nerve Injury 129
Regeneration 130
Degeneration and Regeneration of Nerve 130
Transneuronal Degeneration 130
Applied Physiology 130
Cathode Ray Oscilloscope (CRO) 130
Exam-oriented Questions 131
22. Neuromuscular Junction 132
Introduction 132
Anatomical Considerations 132
Neuromuscular Junction 132
Presynaptic Terminal 132
Synaptic Cleft 133
Post-synaptic Membrane 133
Synthesis of Acetylcholine in Motor Neuron 133
Sequence of Events in Neuromuscular Transmission 133
Neuromuscular Blockers 134
Applied Physiology 134
Exam-oriented Questions 135
23. Classification of Muscular Tissue 136
Introduction 136
Muscle Classification 136
Exam-oriented Question 137
24. Structure of Skeletal Muscle 138
Introduction 138
Distribution 138
Origin and Development 138
General Features 138
Histological Structure of Muscle Fibres 138
Myofibrils: Characteristic Features 138
Myosin Filaments 139
Actin Filament 140
Sarcotubular System 141
Blood Vessels, Lymphatics and Nerves of Skeletal
Muscle 141
Ending of Muscle in Tendon 141
Exam-oriented Questions 142
25. Muscle Contraction 143
Introduction 143
Mechanism of Contraction 143
Molecular Mechanism of Muscle Contraction (Sliding
Filament Theory of AF Huxley and HE Huxley) 143
Changes during Muscular Contraction 146
Role of Creatine Phosphate or Phosphagen and
Adenosine Triphosphate (ATP) 146
Muscular Contraction and its Relationship with the
Breakdown of ATP 147
Oxygen Utilization and CO2
Production 147
Cori Cycle 147
Thermal Changes 148
Electrical Changes 148
Strength–Duration Relationship—Chronaxie and
Rheobase 148
Muscular Disorders 149
Exam-oriented Questions 149
26. Properties of Skeletal Muscle 150
Introduction 150
Excitability and Contractility 150
Refractory Period 154
Tonicity 154
Conductivity 154
Extensibility and Elasticity 154
Contraction of Skeletal Muscle 154
Exam-oriented Questions 155
27. Cardiac Muscle 156
Introduction 156
Blood Vessels, Lymphatics and Nerves of Cardiac
Muscle 158
Exam-oriented Questions 159
28. Smooth Muscles 160
Introduction 160
Histology 160
Contractile Mechanism 161
Properties of Plain (Smooth) Muscles 161
Excitability and Contractility 161
Functions of the Muscular Tissue 163
Rigor Mortis 163
Exam-oriented Questions 163
Clinical Case Scenario 165
Nerve Muscle 165
Recent Update: A Newly Discovered Muscle: The Tensor of
the Vastus Intermedius 166
xiContents
Section IV Cardiovascular System
29. Introduction to Cardiovascular System 170
Introduction 170
Anatomical Considerations of the Heart 171
Key Points 171
Valves of the Heart 172
Action of the Valves 173
Histology of the Cardiac Muscle 174
Valves of the Veins 176
Blood Vessels (Vasa Vasorum) 176
Factors that Maintain Circulation 176
Special Junctional Tissues 176
Sino-atrial Node (Keith and Flack, 1907) 177
Atrioventricular Node (Tawara, 1906) 177
Bundle of His 178
Bundle Branch 178
Purkinje Fibres 179
Exam-oriented Questions 179
30. Initiation and Spread of Cardiac Impulse 180
Origin of the Heartbeat 180
Initiation of Impulse and Localisation of Pacemaker 180
Conduction Over Atrial Muscle 180
Conduction Over AV Node 180
Conduction Over Bundle of His and the Right and Left
Bundle Branches 181
Conduction through Purkinje Systems 181
Conduction through Ventricular Muscle 181
Heart Block 181
Exam-oriented Questions 182
31. Properties of Cardiac Muscle 183
Introduction 183
Rhythmicity 183
Excitability 183
Conduction 184
Contraction 185
All-or-none Response 185
Staircase Phenomenon 185
Refractory Period 185
Tone 185
Functional Syncytium 186
Exam-oriented Questions 186
32. Cardiac Cycle 187
Introduction 187
Cardiac Cycle Time 187
Summary of the Sequence of Events in Cardiac
Cycle 190
Time Relations of the Various Events 191
Summary of the Time Relations 191
Exam-oriented Questions 192
33. Haemodynamics of Circulatory System and Pressure
and Volume Changes during Cardiac Cycle 193
Haemodynamics of Circulatory System 193
Blood Flow through Vessel 193
Structural Overview 193
Overall Blood Flow in Circulation 193
Pattern of Blood Flow 193
Blood Flow Resistance (Peripheral Resistance) 194
Velocity of Blood Flow 194
Lumen of the Blood Vessel 194
Effect of Gravity on Mean Blood Pressure 194
Regulation of Blood Flow 195
Acute Control of Local Blood Flow 195
Long-term Control of Local Blood Flow 195
Role of Humoral Vasoconstrictors and Vasodilators 195
Pressure Volume Changes 196
Methods of Study 196
Pressure Changes 196
Intraventricular Pressure Changes and Assessment 196
Ventricular Systole 196
Ventricular Diastole 196
Intra-atrial Pressure Changes 197
Jugular Pressure Tracing (Venous Pulse) 197
Ventricular Volume Changes 198
Composite Representation of the Sequential Changes in the
Pressure and Volume events in the Heart and Blood
Vessels during the Cardiac Cycle Correlating with
Phonocardiogram and Electrocardiogram 198
Heart Sounds 199
Exam-Oriented Questions 201
34. Electrocardiogram 202
Introduction 202
Methods of Recording Electrocardiogram 202
Electrocardiographic Leads Used both Clinically and
Experimentally 203
Unipolar Limb Leads 205
Augmented Unipolar Limb Leads 206
Normal ECG Recorded in Chest Leads 207
Significance of Various Leads and their Limitations 207
Electrocardiographic Appearances under Certain
Cardiac Disorders 208
ECG Changes in Atrial Tachycardia, Atrial Flutter
and Atrial Fibrillation 208
Ventricular Premature Beat or Extra Systole 209
Ventricular Paroxysmal Tachycardia 209
Ventricular Fibrillation 209
Wolff-Parkinson-White Syndrome 209
Myocardial Infarction 210
Myocardial Infarction: Coronary Ischaemia and
Current Injury 210
Mean Electrical Axis of the Heart 210
Determination of Electrical Axis 210
Ventricular Conditions that may Cause Axis
Deviation 211
Exam-oriented Questions 212
35. Innervations of Heart and Heart Rate 213
Introduction 213
Nerves of the Heart and their Action 213
Vagus Nerves 213
Tonic Action of the Vagus Nerves 214
Sympathetic Nerves 214
Cardiac Centres 214
Heart Rate 214
Factors Affecting Heart Rate 214
Regulation of Heart Rate 215
Applied Physiology 217
Exam-oriented Questions 217
36. Cardiac Output 218
Introduction 218
Normal Values: 5–6 Litres/Minute 218
Important Terminology and Definitions 218
Distribution of Cardiac Output 218
Cardiac Reserve 218
Factors Affecting Cardiac Output 219
Control of Cardiac Output 219
Preload Depends on Ventricular Filling and Venous
Return 219
xiiHuman Physiology
Cardiac Contractility 219
Afterload 220
Methods of Measuring Cardiac Output 221
Dye Method: Stewart and Hamilton’s Dye Dilution
Method 221
Employing for Measuring Cardiac Output
Fick Principle Using O2
and CO2 221
Physical Method: Ballistocardiography 222
Thermo-dilution Method (Cold Saline Method) 222
Applied Physiology 222
Doppler Echocardiography 222
Calculation 222
Exam-oriented Questions 222
37. Blood Pressure 223
Introduction 223
Basal Blood Pressure 223
Physiological Variations 223
Significance of Blood Pressure 224
Systolic Pressure 224
Diastolic Pressure 224
Pulse Pressure 224
Physiological Significance of Blood Pressure 224
Measurement and Recording of Blood Pressure 224
Arterial Blood Pressure 224
Venous Pressure 226
Determinants of Blood Pressure 226
Adjustment of Blood Pressure 226
Efferent Pathways of this Self-adjustment or
Homoeostasis of Blood Pressure 227
Vasomotor System 227
Afferent Pathways 228
Role of Sino-aortic Mechanism in the Regulation of
Normal Blood Pressure 228
Sino-aortic Mechanism 228
Chemoreceptors Location 229
Aortic Bodies 230
Vascular Receptors other than Sino-Aortic for the
Control of Blood Pressure and Flow 230
As Chemoreceptors 231
Mechanism of Regulation of Blood Pressure 231
Short-term Regulating Mechanisms 231
Intermediate Mechanism of Regulation of
Blood Pressure 232
Long-term Regulation of Blood Pressure 232
Role of other Hormone in Regulation of Blood
Pressure 232
Role of Humoral Vasoconstrictors and Vasodilators 232
Humoral Vasoconstrictors 232
Humoral Vasodilators 233
Chemical Control of Blood Pressure Influenced by
Vasomotor Mechanism 233
Exam-oriented Questions 233
38. Velocity of Blood Flow and Radial Pulse 234
Introduction 234
Velocity of Blood 234
Methods of Measurement of Velocity of Blood 234
Radial Pulse 234
Pressure Pulse 235
Recording of Radial Pulse 235
Clinical Features of Radial Pulse 235
Special Varieties of Pulse 235
Applied Physiology 236
Exam-oriented Questions 236
39. Regional Circulation 237
Introduction 237
Coronary Circulation 237
Anatomical Considerations 237
Venous Drainage 238
Methods of Study 238
Normal Values 238
Variations of Coronary Inflow during Different
Phases of Cardiac Cycle 239
Coronary Inflow 239
Factors Influencing Coronary Circulation 240
Circulatory Status of the Cardiac Muscle under
Certain Diseased Conditions 241
Aortic Stenosis 241
Pulmonary Hypertension 241
Aortic Insufficiency 241
Mitral Stenosis 241
Aortic Coarctation 241
Hypertensive Cardiovascular Disease 241
Ischaemic Heart Disease 241
Coronary Spasms and Intercoronary Reflexes 241
Pathological Physiology of Angina Pectoris and
Acute Myocardial Infarction 241
Cerebral Circulation 241
Anatomical Considerations 241
Method of Study: Nitrous Oxide Method:
Fick Principle 242
Vasomotor Supply 242
Normal Values of Cerebral Circulation 242
Regulation of Cerebral Circulation 243
Existence of Auto-regulation of Cerebral Blood Flow 243
Key Points 243
Factors Controlling Cerebral Circulation 243
Cerebrovascular Resistance 243
Pulmonary Circulation 244
Anatomy of Circulation 244
Method of Recording Pulmonary Arterial Pressure 244
Vasomotor Supply 244
Normal Values of Pulmonary Circulation 244
Functions of Pulmonary Circulation 245
Control of Pulmonary Circulation 245
Peculiarities of Pulmonary Circulation 246
Pulmonary Vascular Reflex 246
Circulatory Status in Different Cardiopulmonary
Diseases 246
Mitral Stenosis 246
Emphysema 246
Pulmonary Embolism 246
Atelectasis 246
Removal of Lung 247
Diffuse Sclerosis of Lung Vessels 247
Pulmonary Fibrosis 247
Hepatic Circulation 247
Vascular Arrangement 247
Vasomotor Supply 247
Normal Values of Hepatic Circulation 247
Factors Modifying Hepatic Circulation 248
Peculiarities of Hepatic Circulation 248
Splenic Circulation 249
Control of Blood Flow 249
Renal Circulation 249
Capillary Circulation 249
Histology 249
Methods of Study of Capillary Circulation 249
Vasomotor Supply 249
Control of Capillary Circulation 250
Interchange in the Capillary Area 251
Cutaneous Circulation 251
Anatomy of Cutaneous Circulation 251
Rate of Blood Flow 251
xiiiContents
Regulation of Blood Flow: Nervous Control 251
Vascular Response of Skin 252
Auto-regulation of Skin Blood Flow 252
Normal Colour of the Skin 252
Skeletal Muscle Circulation 253
Vascular Arrangement in Skeletal Muscle 253
Rate of Blood Flow Through Muscle 253
Basal Tone of Arterioles 253
Control of Skeletal Muscle Blood Flow 253
Exam-oriented Questions 254
40. Physiology of Exercise 255
Introduction 255
Muscular Exercise 255
Changes in Cardiovascular System 256
Heart Rate Changes during Exercise 256
Circulatory Status during Exercise 257
Changes in Respiration 258
Blood Cell Changes during Exercise 258
Body Temperature 258
Body Fluid Changes during Exercise 259
Kidney Function in Exercise 259
Digestive System 259
Endocrine Status 260
Aerobic Training 260
Isometric and Isotonic Exercises 260
Cardiovascular and Cardiorespiratory Response to Isometric
Exercise 260
Sedentary Lifestyle and Health Implication 261
Introduction 261
Health Implication in Sedentary Lifestyle 261
Role of Nutrition in Exercise 262
Over-exercising and Ill Effects on Health 262
Cardiorespiratory Changes under Different
Environmental Conditions (Heat and Cold) 262
Exam-oriented Questions 262
41. Applied Cardiovascular Physiology:
Haemorrhage, Heart Failure,
Hypotension, Hypertension and Shock 263
Haemorrhage 263
Compensatory Changes after Haemorrhage 263
Heart Failure 264
Types of Heart Failure 264
Role of Compensatory Mechanisms in Heart Failure 265
Management and Prevention 265
Hypotension 265
Orthostatic Hypotension 265
Hypertension 265
Signs and Symptoms 265
Pathophysiology of Hypertension 266
Shock 267
Types of Shock 267
Clinical Features of Shock 267
Stages of Shock 267
Physiology of Treatment in Shock 270
Applied Physiology: Cardiovascular System 270
Cardiac Disorders 270
Exam-oriented Questions 271
Clinical Case Scenario 272
Cardiovascular System 272
Important Cardiovascular Research Study:
Framingham Heart Study 273
First Cardiac Catheterization and Future
Development of Technique 273
Open-heart Surgery 273
Recent Advances in Cardiovascular Research 273
Section V Respiratory System
42. Functional Organization of Respiratory System 276
Structure of the Respiratory Tract 276
Trachea 276
Functions of Respiratory Tract 276
Reflexes Help in Clearing Irritating agents from
Respiratory Passage 277
Respiratory Units 277
Broncho-pulmonary Anastomosis 277
Pulmonary Alveoli 277
Respiratory Functions of Lung 278
Pleural Cavity and Intra-pleural Pressure 279
Intra-pleural Pressure 279
Surface Tension at the Fluid–Air Interface within the
Alveoli and the Role of Surfactant 279
Pressure Changes in the Pleural Cavity and its Relation to
Volume Changes in the Lungs 280
Exam-oriented Questions 280
43. Mechanics of Breathing 281
Introduction 281
Diaphragm 281
Intercostal Muscles 282
Motion of the Ribs during Inspiration and
Expiration 282
Accessory Muscles of Respiration 283
Resistance to Breathing 283
Elastic Resistance 283
Lung Compliance 283
Measurement of Lung Compliance and Pressure–
Volume Curve 283
Viscous or Non-elastic Resistance 284
Elastic Forces and Characteristics of Compliance Pressure–
Volume Curve 284
Elastic Forces of Lung Tissue 284
Alveolar Radius and its Relation to Surface tension 284
Energy Utilization for Respiration 285
Applied Physiology 285
Exam-oriented Questions 286
44. Pulmonary Volumes and Capacities (Spirometry) 287
Introduction 287
Lung Volumes 288
Tidal Volume (TV = 500 ml) 288
Respiratory Minute Volume (RMV) 288
Inspiratory Reserve Volume (IRV) 288
Expiratory Reserve Volume (ERV) 288
Residual Volume (RV) 288
Lung Capacities 288
Inspiratory Capacity (IC) 288
Functional Residual Capacity (FRC) 288
Total Lung Capacity (TLC) 288
Vital Capacity (VC) 288
Forced Expiratory Volume (FEV) 289
Functional Residual Capacity (FRC) 290
Forced Vital Capacity (FVC) 291
Forced Expiratory Volume in 1 (FEV1) Second 291
FEV1/FVC Ratio (FEV1
%) 291
Forced Expiratory Flow (FEF) 291
Peak Expiratory Flow (PEF) 291
Breathing Reserve (BR) 292
Applied Physiology: Obstructive and Restrictive
Lung Disease 292
Exam-oriented Questions 292
xivHuman Physiology
45. Alveolar Ventilation and Gases Exchange
in Lungs 293
Alveolar Ventilation 293
Respiratory ‘Dead Space’ 293
Definition 293
Measurement of Dead Space Volume 293
Nitrogen Meter Method 293
Intrapulmonary Gas-mixing or Even Distribution of
Inspired Air 294
Methods of Detection of Uneven Ventilation 294
Alveolar Air 294
Composition of Alveolar Air 294
Partial Pressure of Gases in Inspired Air, Expired Air
and Alveolar Air 295
Effect of Voluntary Hyperpnoea on Alveolar Air 295
Breath-holding Time 295
Effects of High Altitude on Alveolar Oxygen 296
Factors Controlling Alveolar pCO2 296
Anatomical Shunt 296
Physiological Shunt 297
Applied Physiology 297
Hyperventilation and Hypoventilation 297
Exam-oriented Questions 297
46. Ventilation and Perfusion in Lungs 298
Diffusion 298
Factors Controlling Diffusion 299
Summary of Factors Affecting Diffusion through
Fluids and Respiratory Membrane 299
Diffusion through Respiratory Membrane 299
Pulmonary Diffusing Capacity for O2
(DO2
) 299
Diffusion of CO2 300
Perfusion 300
Applied Physiology 300
Exam-oriented Questions 300
47. Transport of Oxygen and Carbon
Dioxide in Blood 301
Introduction 301
Oxygen Transport 301
Percentage Saturation of Haemoglobin 302
Dissociation Curve for Haemoglobin 302
Nature of the Curve 303
Explanation of the Sigmoid Shape of the Curve 303
Oxygen Exchange in the Lungs 304
Oxygen Transport in the Tissues 304
Applied Physiology 305
Carbon Dioxide Transport 305
CO2 Content and Tension of Blood 305
Transport 305
Carbon Dioxide Dissociation Curves 306
Summary: Transport of Oxygen and Carbon
Dioxide in Blood 308
Exam-oriented Questions 308
48. Regulation of Respiration 309
Introduction 309
Respiratory Centre 309
Dorsal Respiratory Group (DRG) of Neurons and
Inspiratory Ramp Signals 310
Ventral Respiratory Group of Neurons 310
Mechanism of Rhythmic Respiration 310
Role of Abdominal Muscles in Respiration 310
Role of Reflex in Respiration 310
Voluntary Control of Respiration 313
Chemical Control of Respiration 313
CO2
and Respiration 313
Nervous Factors Influencing Respiration in Exercise 315
Periodic Breathing 315
Cheyne-Stokes Breathing 315
Factors Involved in Development of Cheyne-Stokes
Breathing Pattern 315
Mechanism of Cheyne-Stokes Breathing 317
Kussmaul’s Breathing 317
Exam-oriented Questions 317
49. Hypoxia 318
Definition 318
Classification of Hypoxia 318
Anoxic Hypoxia or Arterial Hypoxia 318
Causes of Arterial Hypoxia 318
Anaemic Hypoxia 319
Stagnant Hypoxia or Hypokinetic Hypoxia 319
Histotoxic Hypoxia 319
Altitude Hypoxia 319
Oxygen Therapy in Hypoxia 320
Dyspnoea 321
Dyspnoea due to Alteration in Chemical Composition
of Blood 321
Factors Affecting Diffusion of Gases Across the
Alveolo-capillary Membrane (Alveolo-capillary
Block Syndrome) 321
Excessive Work of the Respiratory Muscles 322
Applied Physiology 322
Psychogenic or Emotional Dyspnoea 322
Exam-oriented Questions 322
50. Compressed Air Sickness and Deep Sea Diving 323
Dysbarism (Caisson Disease) 323
Exam-oriented Question 323
51. Respiration in Abnormal Conditions 324
Asphyxia 324
Definition 324
Classification 324
Essential Conditions of Asphyxia 324
Hyperpnoea 324
Causes 324
Effects of Voluntary Hyperpnoea 324
Orthopnoea 326
Cyanosis 326
Factors Causing Cyanosis 326
Applied Physiology 326
Exam-oriented Questions 327
52. Artificial Respiration or Resuscitation 328
Methods of Artificial Respiration 328
Manual Methods 328
Sylvester’s Method 329
Holger-Nielsen Method 329
Mouth-to-mouth Method 329
Eve’s Rocking Method 329
Instrumental Method 329
Drinker’s Method 329
Resuscitator 329
In the Newborn Baby 329
Exam-oriented Questions 331
53. Acclimatisation 332
Compensatory Changes at Moderately High
Altitude 332
Changes in Acclimatisation 332
Natural Acclimatisation of Natives Residing at High
Altitude 332
Acute Mountain Sickness 333
xvContents
Mountaineering 333
Atmosphere High Altitude Physiology 334
Hypoxia 334
Problem Faced by Aviators 334
Radiation Hazards 335
Dysbarism at High Altitude (Decompression
Sickness) 335
Explosive Decompression 335
Effect of Centrifugal Acceleratory Forces 336
Protection of Body against Centrifugal Acceleratory
Forces 336
Parachute Jump 337
Weightlessness in Space (Zero-G State) 338
Exam-oriented Questions 338
54. Underwater Physiology 339
Introduction 339
Nitrogen 339
Oxygen 339
Mechanism of Oxygen Poisoning 340
Carbon Dioxide 340
Helium 340
Underwater Respiration 340
SCUBA Diving 341
Exam-oriented Question 341
55. Vocalisation and Basic Life Support (BLS) 342
Vocalisation 342
Articulation and Resonance 343
Basic Life Support (BLS) 343
Basic Life Support Sequence 343
Collapsed Victim 343
CAB 344
Compressions 344
Automated External Defibrillators (AEDs) 344
Airway and Ventilations 345
Opening the Airway 345
Ventilations 345
Choking 346
Adult Choking Sequence 347
Unresponsive Victim 347
Chain of Survival 347
Exam-oriented Questions 347
Clinical Case Scenario 348
Respiratory System 348
Recent Advances 348
Section VI Gastro-intestinal Tract
56. General Outline of Digestive System 350
Introduction 350
Anatomical Consideration 350
Histological Structure 351
Innervation of the Digestive Tract 351
Functions of the Digestive System 352
Histology of Tongue 352
Glands 355
Nerve Supply 355
Functions 355
Salivary Glands 355
Histology of Salivary Glands 355
Pharynx or Throat Cavity 357
Oesophagus 357
Histology 357
Stomach 358
Histology of Stomach 359
Functions of Stomach 360
Small Intestine 360
Vermiform Appendix 362
Large Intestine 362
Rectum 362
Anal Canal 362
Brief Summary of the Chief Identifying Features of Different
Parts of the Digestive Tract 362
Exam-oriented Questions 362
57. Digestive Juices 363
Introduction 363
Saliva 363
Characteristics 363
Composition 363
Functions 363
Gastric Juice 364
Composition 364
Characteristics 364
Functions 364
Pancreatic Juice 364
Characteristics 364
Succus Entericus 365
Characteristics 365
Composition 365
Intestinal Juice Enzymes 365
Carbohydrate Splitting 365
Functions 365
Biles 365
Introduction 365
Composition of Bile 366
Functions of Bile 366
Bile Salts 367
Variety and Chemistry 367
Synthesis of Bile Salts 367
Enterohepatic Circulation and Fate of Bile Salts 367
Functions of Bile Salts 367
Bile Pigments 368
Chemistry and Varieties 368
Origin and Formation 368
Site of Formation, Circulation and Fate 368
Exam-oriented Questions 370
58. Mechanism of Secretion of Various
Digestive Juices 371
Introduction 371
Saliva 371
Nerve Supply of Salivary Glands 371
Significance of Double Nerve Supply 372
Salivary Secretion and Reflexes 372
Reflex Control of Rate of Flow and Composition of
Saliva 373
Disturbances of Salivary Secretion 373
Gastric Secretions 373
Cephalic Phase 374
Gastric Phase 375
Gastric Phase Characteristic Features 375
Intestinal Phase 375
Action of Other Hormones on Gastric Secretion 376
Interrelation between the Different Phases 377
Gastric Function Test 377
Investigation of Gastric Secretion in Man 377
Other Functional Tests 378
Origin and Character of the Important Constituents
of Gastric Juice 379
Hydrochloric Acid 379
Applied Physiology: Peptic Ulcer 379
Pepsin 380
Mucin 380
Intrinsic Factor 380
xviHuman Physiology
Neuropoietic Factor 380
Pancreas 380
Development 381
Mechanism of Pancreatic Secretions 381
Nervous Phase 381
Chemical Phase 382
Influence of Various Foodstuffs on Pancreatic
Secretion 383
Applied Physiology 383
Liver 383
Anatomy 383
Gall Bladder: Structure and Functions 383
Mechanism of Bile Secretion 384
Mechanism of Secretion 384
Mechanism of Expulsion of Bile 385
Factors Controlling Movements of Gall Bladder 385
Functions of Gall Bladder 386
Applied Physiology 386
Mechanism of Secretion of Succus Entericus
(Intestinal Juice) 386
Mechanism 387
Applied Physiology 387
Summary of Secretions of the Various Digestive
Juices 387
Exam-oriented Questions 388
59. Movements of Alimentary Canal 389
Introduction 389
Facts about Movement 389
Cause of Movements 389
Relation with Degree of Activity 389
Deglutition (Swallowing) 389
Common Disturbances in the Swallowing 391
Movements of Stomach 391
Applied Physiology 393
Vomiting (Emesis) 393
Movements of Small Intestine 395
Frequency 395
Movements of Villi 397
Applied Physiology 397
Movements of Large Intestine 397
Functions of Large Intestine 398
Rate of Progress of Barium Meal 398
Applied Physiology—Large Intestine 400
Defaecation 400
Mechanism 400
Exam-oriented Questions 400
60. Digestion and Absorption of Foodstuffs 401
Introduction 401
Digestion of Carbohydrates 401
Introduction 401
Different forms of Carbohydrates 401
Digestion of Proteins 402
Introduction 402
Different Forms of Protein 403
Digestion of Nucleoprotein 403
Digestion of Casein 403
Digestion of Milk 404
Digestion of Collagen and Gelatin 404
Digestion of Mucin 404
Digestion of Lipids 404
Digestion in the Pancreatic Juice 404
Absorption 405
Definition 405
Absorption of Carbohydrates 405
Absorption of Proteins 405
Fats Absorption 406
Process of Absorption 406
Water Absorption 406
Absorption of Electrolytes 406
Faeces 407
Contents and Characteristics 407
Exam-oriented Questions 407
61. Gastro-intestinal Hormones 408
Introduction 408
Gastrin 408
Cholecystokinin (CCK) or Pancreozymin 409
Regulation of Secretion of Cholecystokinin 409
Glucagon-like Peptide-1 409
Gastric Inhibitory Polypeptide (GIP) 409
Vasoactive Intestinal Peptide (VIP) 409
Urogastrone 409
Villikinin 409
Enterocrinin 410
Motilin 410
Neurotensin 410
Somatostatin 410
Gastrin Releasing Peptide 410
Ghrelin 410
Peptide YY 410
Substance P 410
Bombesin 410
Exam-oriented Questions 410
Clinical Case Scenario 411
Gastrointestinal Tract 411
Recent Advances: Treatment of Peptic Ulcer 411
Recent Advances: Capsule Endoscopy 412
Section VII Renal Physiology
62. Functional Anatomy of Excretory System 414
Introduction 414
Kidneys 414
Characteristic Features 414
Nephron 415
Uriniferous Tubules 416
Types of Nephrons 416
Renal Tubules 419
Proximal Convoluted Tubule (PCT) 419
Henle’s Loop 419
Distal Convoluted Tubule (DCT) 420
Collecting Tubule 421
Juxtaglomerular Apparatus 421
Regulation of Renin Secretion 422
Renal Circulation 423
Peculiarities 423
Peculiarities of Renal Circulation 425
Exam-oriented Questions 426
63. Urine Formation by Kidneys: Renal Blood Flow
and their Control 427
Introduction 427
Autoregulation of Renal Blood Flow 427
Nervous Control 428
Other Factors 429
Blood Glucose Level 429
Hormones Influencing Renal Functions 429
Measurement of Renal Blood Flow 429
Functions of Kidney and Glomerulus 430
Functions of Kidney 430
Exam-oriented Questions 430
xviiContents
64. Urine Formation by the Kidney: Glomerular
Filtration Rate and their Control 431
Introduction 431
Key Points 431
Glomeruli as Ultrafilter 433
Functions of Glomerulus 433
Applied physiology: Chronic Kidney Disease and
Glomerular Filtration Rate 435
65. Tubular Reabsorption and Tubular Secretion (Urine
Formation): Water and Electrolytes Balance and
Counter-current Mechanism 436
Introduction 436
Methods of Study of Tubular Functions 436
Selective Reabsorption 436
Glucose 436
Water 437
Sodium and Chloride 439
Potassium 439
Bicarbonate 441
Phosphate 442
Reabsorption of other Substances 442
Tubular Secretion 442
Formation of Some New Substances 442
Exam-oriented Questions 444
66. Renal Function Test, Urine, Urinary
Characteristic and its Mechanism of Formation 445
Introduction 445
Assuming 445
I. Test for measurement of GFR 446
Inulin Clearance (A Measure of Glomerular
Filtration Rate) 446
Creatinine Clearance Test 446
II. Test to Measure Excretory Function 446
Urea Clearance Test (Van Slyke) 446
III. Test to Estimate Tubular Secretion Capacity 447
IV. Test to Measure Renal Blood Flow 447
Urine, Urinary Characteristic and its Mechanism of
Formation 447
Introduction 447
Other Characteristics 448
Colour 448
Reaction 448
Specific Gravity 448
Turbidity 448
Odour 448
Osmotic Pressure 448
Composition of Urine 448
Normal Constituents of Urine 448
Abnormal Constituent of Urine 449
Protein 449
Glucose 450
Ketone Bodies 450
Presence of Blood in Urine 450
Pigments 450
Calculi and Casts 450
Pus 450
Hormones 450
Factors Affecting Formation of Urine 451
Reaction of Urine 451
Mechanism of Regulation of Blood Reaction by
the Kidneys 451
Bicarbonate Mechanism 451
Phosphate Mechanism 452
Ammonia Mechanism 453
Elimination of Acids 453
Elimination of Alkalis 454
Glycosuria 454
Glycosuria due to Hyperglycaemia 454
Glycosuria due to Less Tubular Reabsorption 455
Factors Controlling Volume of Urine 455
Abnormal Volume of Urine 456
Applied Physiology 456
Exam-oriented Questions 457
67. Micturition 458
Introduction 458
Structure of Urinary Bladder 458
Mechanism of Filling of Bladder 459
Mechanism of Micturition 459
Key Features 459
Micturition Reflex 460
Centres of Micturition 461
Effect of Lesion of Autonomic Nerves 461
Applied: Pathological Conditions involving Bladder
Control Physiology 462
Artificial Kidney 463
Exam-oriented Questions 463
68. Skin, Body Temperature and its Regulation 464
Introduction 464
Structure 464
Epidermis 464
Dermis (Cutis Vera or True Skin) 465
Functions of Skin 465
Glands in the Skin 466
Mechanism of Secretion of Sweat 466
Composition of Sweat 467
Sebaceous Glands 467
Composition of Sebum 467
Control 467
Special Structures of Skin 469
Nails (Ungues) 469
Hair (Pili) 469
Body Temperature and its Regulation 470
Introduction 470
Factors Affecting Body Temperature 470
Regulation of Body Temperature 471
Mechanisms of Heat Production (Thermogenesis) 471
Mechanisms of Heat Loss (Thermolysis) 472
Nervous System and Thermotaxis 472
Interaction of Central and Peripheral Factors 473
Role of Endocrines 474
Temperature Regulation in the Newborn Infant 474
Mechanism of Regulation of Body Temperature 474
Decreased Body Temperature and Responses 474
Other Factors 474
Effects of Exposure to High and Low Atmospheric
Temperature 474
Physiological Alterations of Body Mechanisms on
Exposure to Hot Atmosphere 474
Life in Deserts 475
Physiological Alterations of Body Mechanisms on
Exposure to Cold Atmosphere 476
Effect of Sudden Change of Atmospheric
Temperature 476
Pyrexia 476
Physiological Responses due to Pyrexia (Fever) 476
Hypothermia 476
Physiological Responses to (Deliberate)
Hypothermia 476
xviiiHuman Physiology
Applied Physiology 477
Exam-oriented Questions 478
69. Regulation of Reaction of Blood and
Disturbances in Acid–Base Regulation 479
Introduction 479
Respiratory H+ 479
Metabolic H+ 479
Acid–base, Hydrogen Ion Concentration and pH 479
Acid and Base 479
Hydrogen Ion Concentration 480
pH 480
Calculation of pH 480
Calculation of [H+] Ion Concentration 480
The pH Scale 480
Physiological Importance of Maintenance of pH 481
Buffers, Lungs and Kidney 482
Buffer Action 482
Bicarbonate Buffer System 482
Bicarbonate Buffer System and its importance as
Extracellular Buffer 482
Role of Kidney and Lung 482
Role of Respiration in Acid–Base Balance 484
Role of Kidneys in Acid–Base Balance 484
Disturbances in Acid–Base Regulation 485
Respiratory Acidosis 485
Definition 485
Pathophysiology 485
Compensatory Mechanism 485
Metabolic Alkalosis 485
Definition 485
Respiratory Compensation 486
Renal Compensation 486
Metabolic Acidosis 486
Definition 486
Compensation 486
Respiratory Alkalosis 486
Definition 486
Renal Compensation 487
Assessment of the Acid–Base Status 487
Exam-oriented Questions 487
Clinical Case Scenario 488
Kidney 488
Applied Physiology 489
Peritoneal Dialysis 489
Renal Transplantation 489
Multiple Choice Questions
General Physiology 492
Blood 496
Nerve and Muscle 500
Cardiovascular System 504
Respiratory System 508
Gastro-intestinal Tract 511
Renal System 515
References 519
Appendix A1–A5
Index I1–I

ntroduction 522
Storage, Destruction and Excretion 523
Mode of Action 523
Cyclic AMP and Hormone Action 523
Cyclic Guanosine Monophosphate (cGMP) as Second
Messenger 524
Diacylglycerol (DAG) and Inositol 1,4, 5-Triphosphate
(IP3) as Second Messenger 524
Ca2+ as a Second Messenger 524
Synthesis of Enzyme at the Nuclear Level 524
Other Mechanisms 526
Control of Endocrine System: Regulation of Secretion of
Hormones 526
Negative Control Mechanism 527
Endocrine Glands 527
Essential Properties of a Hormone 528
Major Endocrine Glands and Hormones in Controlling
Body Functions 528
Neuroendocrine Interrelations 528
Hypothalamic Hypophyseal Portal System 528
Hypothalamo-hypophyseal Peripheral Gland Axis 529
Exam-oriented Questions 530
71. Hypophysis (Pituitary Gland) 531
Introduction 531
Structure and Functions of Adenohypophysis (Anterior
Pituitary) 533
Blood Supply 534
Functions of the Anterior Lobe of Pituitary Gland 534
Growth Hormone or Somatotropin (GH or STH) 534
Chemistry 534
Synthesis of Growth Hormone 535
Growth Hormone Secretion 535
Mechanism of Action 535
Actions of Growth Hormone (GH) 535
Regulation of Growth Hormone Secretion 536
Applied Physiology (Growth Hormone Pathological
Disorders) 536
Growth Hormone Disorders 536
Hyperactivity of Somatotropes 536
Hypoactivity of Somatotropes 536
Gigantism 536
Characteristic Features 537
Acromegaly 537
Characteristic Features 537
Dwarfism 538
Lorain-Levy Type (Infantilism) 538
Brissaud Type (Fat Body of Dickens) 538
Mixed Type 538
Acromicria 538
Preface to the Fourteenth Edition v
Preface to the First Edition vi
Thyrotropic Hormone or Thyrotropin or Thyroid-Stimulating
Hormone (TSH) 538
Chemistry 538
Control of TSH Output 538
Control of Thyrotropin-Releasing Hormone Output 539
Gonadotropic Hormones (GTH) or Gonadotropins:
FSH and LH 539
Functions of FSH 540
Functions of LH 540
Prolactin (PRL) 540
Control of Prolactin Secretion 540
Reflex Stimulation of Prolactin 540
Action of Prolactin 541
Physiological Functions 541
Central and Peripheral Organizations of Anterior
Pituitary Hormones 541
Mechanism of Releasing Factors 542
Disorders of Pituitary Gland 542
Pars Intermedia 544
Pars Tuberalis or Infundibularis 544
Structure and Functions of Neurohypophysis
(Posterior Lobe) 544
Posterior Lobe of Pituitary Gland 544
Blood Supply 544
Nerve Supply 545
Synthesis, Transport and Storage of the
Neurohypophyseal Hormones in the
Hypothalamo-hypophyseal System 546
Chemistry 546
Vasopressin (Pitressin) 546
Chemistry 546
Synthesis 546
Regulation of Secretion 546
Units of Vasopressin 547
Mode of Action 547
Control of the Secretion of Vasopressin (ADH) 547
Non-osmotic Stimuli of ADH Secretion 548
Actions of ADH 548
Applied Physiology 548
Oxytocin (Pitocin) 548
Source 548
Synthesis 548
Unit of Oxytocin 548
Regulation of Secretion 548
Control of Secretion of Oxytocin 548
Actions of Oxytocin 549
Integrative Action of Neuroendocrinology 550
Introduction 550
Conclusion 550
Neuroendocrine Integration 551
Exam-oriented Questions 551
72. Thyroid Gland 552
Introduction 552
Anatomy 552
Histology 553
Contents
viiiHuman Physiology
Thyroid Hormones 554
Synthesis, Storage, Release and Transport of Thyroid
Hormones–Iodine Metabolism 554
Synthesis of Thyroid Hormones 554
Transport of Thyroid Hormones 554
Degradation and Excretion of Thyroid Hormones 555
Mechanism of Action of Thyroid Hormone via its
Nuclear Receptors 555
Iodine Requirement and Anterior Pituitary Control in
Secretion of Thyroid Hormone 556
Iodine 556
Role of Anterior Pituitary 556
Physiological Actions of Thyroid Hormones 556
Regulation of Thyroid Hormones 557
Functions of Thyroid Hormones 557
Metabolism 557
Thermogenesis and Body Weight 557
Growth and Differentiation 557
Cardiovascular System 559
Central Nervous System 559
Reproductive System 559
Calorigenic Effect: Heat Regulation 559
Relation with Vitamins 559
Effect on Bone and Mineral Metabolism 559
Secretion of Milk 559
Other Functions 559
Thyroid Disorders 559
Hypothyroidism 559
Cretinism 559
Myxoedema 560
Goitre 560
Hyperthyroidism Thyrotoxicosis 561
Graves’ Disease (Basedow’s Disease or
Exophthalmic Goitre) 561
Treatment of Thyrotoxicosis 562
Thyroid Function Tests 562
Blood Tests 562
Autoimmune Markers 563
Tests Based on Use of Nuclear Medicine 563
Thyroid Ultrasound 563
Fine Needle Aspiration Biopsy 563
Thyrotropin-Releasing Hormone (TRH) Response
Test 563
Control of Thyroid Secretion and Endocrine
Interrelationship 563
Role of Anterior Pituitary 563
Role of Sympathetic and Parasympathetic Nerves
(Vasomotor Regulation) 563
Stress Phenomena 563
Thyroid–Gonadal Interrelationship 563
Antithyroid Compounds 563
Exam-oriented Questions 564
73. Calcium Homeostasis: Role of Parathyroid Gland 565
Calcium 565
Sources 565
Distribution of Calcium in the Body 565
Blood Calcium 565
Absorption of Calcium from the Gut 565
Applied Physiology 566
Calcium Excretion 566
Calcium Balance 566
Functions 566
Daily Requirement 567
Phosphorus 567
Sources 567
Distribution 567
Blood Phosphorus 567
Absorption 567
Control of Phosphorus Metabolism 567
Excretion of Phosphorus 567
Functions 567
Daily Requirement 568
Relationship between Plasma Ionized Calcium and
Phosphate 568
Calcitriol 568
Formation of Calcitriol 568
Excretion 568
Action of Calcitriol 568
Therapeutic uses 568
Functions of Calcitriol 568
Role of Other Hormones in Regulating Calcium
Metabolism 568
The Parathyroid 568
Anatomy 568
Histology 569
Parathyroid Hormone 569
Control of Parathyroid Secretion 569
Physiological Functions of Parathyroid Gland 569
Tetany in Man 570
Disorders of Parathyroid Secretion 571
Calcitonin 572
Introduction 572
Chemistry 572
Synthesis 572
Regulation of Secretion 572
Action of Calcitonin 572
Bone 573
Composition of Bone 573
Structure of Bone 573
Bone Formation and Resorption 573
Functions of Bone 574
Applied Physiology 574
Exam-oriented Questions 574
74. Pancreas 575
Introduction 575
Endocrine Pancreas 575
Histology 575
Nerve Supply 576
Insulin 576
Chemistry 576
Synthesis, Storage and Release of Insulin 576
Glucose Transporters 577
Insulin Secretion 577
Fate and Degradation of Insulin 578
Regulation of Secretion of Insulin 578
Control of Insulin Secretion 579
Action of Insulin 579
Glucose Tolerance Test 580
Somatostatin 580
Synthesis 580
Action of Somatostatin 580
Applied Physiology 580
Pancreatic Polypeptide 580
Secretion 580
Action 580
Applied Physiology 580
Glucagon 580
Synthesis of Glucagon 581
Secretion of Glucagon 581
Metabolism and Degradation 581
Action of Glucagon 581
Applied Clinical Physiology 581
Applied Physiology 581
Hypoglycaemia 581
Hyperinsulinism 582
Hyperglycaemia 582
Glycosuria 583
Diabetes Mellitus 583
Exam-oriented Questions 586
75. Adrenal (Suprarenal) Glands 587
Anatomy 587
Blood Supply 587
Nerve Supply 587
Adrenal Cortex 588
Histology 588
Active Principles of Adrenal Cortex and their Functions 588
Active Principles 588
Adrenal Corticoids 588
Biosynthesis of Adrenal Steroid Hormones 590
Transport, Metabolism and Excretion 590
Mechanism of Action of Adrenal Steroids 590
Functions of Adrenal Hormones 591
Functions of Adrenal Cortex 591
Hypofunction of Adrenal Cortex 592
Addison’s Disease 592
Hyperfunction of Adrenal Cortex 592
Cushing’s Syndrome 592
Hyperaldosteronism 593
Adrenogenital Syndrome 593
Laboratory Studies for Adrenocortical Functions 594
Control of Cortical Secretion 594
Hormonal Control 594
Nervous Control 594
Inorganic Control 594
Blood Volume 595
Mineralocorticoids 595
Renin-Angiotensin Mechanism 595
Function of Mineralocorticoids (Aldosterone) 595
General Adaptation Syndrome 596
Adrenal Medulla 597
Histology 597
Electron Microscopic Structure of Adrenal Medullary
Cells 597
Adrenal Medullary Hormones 597
Biosynthesis of Adrenomedullary Hormones 597
Release of Catecholamines 598
Epinephrine (Adrenaline) 600
Norepinephrine (Noradrenaline) 602
Functions of Adrenal Medulla 603
Applied Physiology 603
Methods of Functional Study of Adrenal Medulla 603
Endocrine and Metabolic Complications of Obesity and
Metabolic Syndrome 605
Psychiatric and Psychological Manifestation in Metabolic
Syndrome 606
Exam-oriented Questions 606
76. Local Hormones 607
Introduction 607
Erythropoietin 607
Physiological Basis 607
Action 607
Renin 607
Histamine and Heparin 607
Synthesis 607
Action 607
The Prostaglandins 608
Chemistry 608
Distribution 608
Mode of Action 608
Synthesis of Prostaglandins 608
Actions 608
Functions of Prostagladins 608
Conclusion 609
Serotonin 610
Synthesis 610
Actions 610
Bradykinin 610
Synthesis 610
Actions 610
Endothelins 610
Synthesis 610
Actions 610
Atrial Natriuretic Peptide 610
Synthesis 610
Actions 610
Adrenomedullin 611
Adenosine Derivatives 611
Gastrointestinal Hormones 611
Exam-oriented Questions 611
77. Thymus 612
Introduction 612
Anatomy 612
Development 613
Histology 613
Blood Vessels and Nerve Supply 613
Clinical Evidences of Thymic Function 614
Applied Physiology 614
Thymic Disorders and Genesis 614
Exam-oriented Questions 614
78. The Pineal Body 615
Introduction 615
Anatomy 615
Histology 615
Concretions 615
Changes with Age 615
Melatonin 615
Control of Synthesis and Release of Melatonin 615
Important Characteristics of Melatonin and Functions of
Pineal Glands 617
Exam-oriented Questions 617
Clinical Case Scenario 618
Section IX Reproductive System
79. Gonads and Reproduction 622
Introduction 622
Gonadal Function 622
Reproduction 622
Puberty 623
Puberty Changes 623
Development of Gonads 623
Applied Physiology 623
Psychological and Clinical Correlation in Adolescence 624
Genetic Basis of Sex Differentiation 624
Sex Chromatin 625
Chromosomal Abnormalities in Sex Differentiation 626
Abnormalities due to Maternal Nondisjunction 626
Abnormalities due to Paternal Nondisjunction 626
Other Chromosomal Abnormalities in Sex
Differentiation 627
Sex Differentiation due to Hormones 628
Practical and Psychiatric Implication of Sex
Determination 628
Exam-oriented Questions 628
80. Male Reproductive Organs 629
Introduction 629
Testis 629
Anatomy 629
Histology 630
Seminiferous Tubules 631
Interstitial Cells (Cells of Leydig) 631
Functions of Testis 631
Androgens 632
Chemistry and Varieties 632
Sources 633
ixContents
x Human Physiology
Biosynthesis of Androgens in the Testis 633
Mode of Action of Testosterone and other
Androgens 633
Transport, Metabolism and Excretion of
Testosterone 634
Functions of Androgens: Testosterone 634
Hormonal and Neural Control of Testosterone
Secretion 636
Other Testicular Hormones 636
Life History of Spermatozoa (Sperms) 636
Histology 636
Spermatogenesis 638
Stages of Spermatogenesis 639
Control of Spermatogenesis 639
Motility and Fertilizing Power of Sperm 640
Fate of Spermatozoa 640
Metabolism of Spermatozoa 640
Hyaluronidase 640
Fertilization of the Ovum 640
Semen (Seminal Plasma or Fluid) 641
Functions of the Constituents of Seminal Fluids 642
Applied Physiology
Impotence 643
Male Sexual Act 643
Hypogonadism 644
Prostate 644
Histology 644
Functions 644
Control of Prostate 644
Proof 644
Applied Physiology: Prostatic Hypertrophy 645
Summary: Functions of Testosterone 645
Exam-oriented Questions 646
81. Female Reproductive Organs 647
Introduction 647
Anatomy 647
Fallopian Tube 647
Histology 647
Cervix 648
Vagina 648
Ovary 648
Structural Anatomy 648
Histology 648
Functions of Ovary 649
Life History of Vesicular of Graafian Follicles 650
Development and Histology 650
Maturation of the Ovum 651
Covering of the Ovum 651
Control of Maturation of Ovum 651
Ovulation 652
Fertilization 654
Implantation 654
Fate of Graafian Follicles 655
Functioning of Graafian or Vesicular Follicle 655
Atretic Follicles 655
Life History of Corpus Luteum 655
Maintenance of Corpus Luteum 656
Hypophyseal and Other Factors in Luteolysis 657
Oestrogens 657
Definition 657
Types 657
Synthesis of Oestrogens 658
Metabolism and Excretion 659
Mechanism of Action of Oestrogens 659
Actions of Oestrogen 659
Functions of Oestrogen 660
Progesterone 661
Sources 661
Varieties and Chemistry 661
Synthesis of Progesterone 662
Metabolism and Excretion 662
Mechanism of Action 662
Action of Progesterone 662
Functions of Progesterone 663
Relaxin 663
Androgens 663
Control of Ovarian Functions 663
Menstruation 664
Definition 664
Changes and Influence of Hormone in Menstrual
Cycle 664
Menopause or Female Climacteric 667
Role of the Central Nervous System (CNS): In Hypophysealovarian Axis 668
Exam-oriented Questions 669
82. Pregnancy 670
Introduction 670
Physiological Changes during Pregnancy 670
Other Changes 671
Pregnancy Tests 671
Biological Tests 671
Placenta 672
Formation and Development 672
Histology 672
Functions of the Placenta 673
Hormonal Regulation in Pregnancy 676
Exam-oriented Questions 677
83. Parturition 678
Introduction 678
Process of Parturition 678
Involution 679
Applied Physiology 679
Twins and Multiple Births 679
Exam-oriented Questions 679
84. Foetal Circulation 680
Introduction 680
Peculiarities in Foetal Circulation 680
Course of Circulation 680
Challenges of New Existence 682
Changes in Circulation after Birth 682
Changes in the Lungs and Respiration 683
Cardiovascular System Status at Time of Birth 683
Blood Cell Count in Newborn 683
Gastrointestinal Functions in Newborn 683
Renal Functions in Newborn 683
Regulation of Body Temperature in Newborn 683
Applied Clinical Physiology: Inborn Errors of Metabolism in
the Newborn 684
Galactosaemia 684
Phenylketonuria 684
Infancy 684
Exam-oriented Questions 685
85. Development of Breast and Lactation 686
Introduction 686
Control of Breast Development and Lactation 686
Development of Mammary Glands 686
Lactogenesis: Secretion of Milk 686
Galactopoiesis (Maintenance of Lactation) 686
Ejection of Milk 687
Effects of Suckling 687
Inhibition 688
Colostrum 688
Nutritional Needs of Infant 688
Human Milk 688
Applied Physiology 689
Exam-oriented Questions 689
86. Controlled Reproduction and Family Planning 690
Introduction 690
Physiological Methods 690
Use of Some Barriers to the Entry of Sperms into the
Cervix at the time of Coitus 690
Use of Chemical Spermicidal Agents before or after
Intercourse 690
Interruption of Normal Paths of the Sperms or Ovum 691
IUCD 691
Contraceptive Pills 691
Different Varieties of Pills 692
Side Effects of the ‘Pills’ 692
Infertility and IVF 692
Infertility 692
Procedure of IVF 693
Role of IVF in Management of Infertility 693
Other Methods 694
Exam-oriented Questions 694
Clinical Case Scenario 695
Reproduction 695
In Vitro Fertilization: 2010 Nobel Prize for Physiology and
Medicine 695
Section X Nervous System
87. Introduction to Nervous System 698
Introduction 698
Central or Somatic Nervous System 698
Spinal Cord 698
Brain 699
Meninges, Ventricles and Cerebrospinal Fluid 701
Blood Supply 705
Metabolism 705
Exam-oriented Questions 705
88. General Principles of the Nervous System 706
Introduction 706
Afferent and Efferent 706
General Functions of Nervous System 706
Classification of Neurotransmitters 707
Nature of Transmission in the CNS: Small Molecule
Transmitters 707
Acetylcholine: Cholinergic Transmission 707
Central Adrenergic Transmission: Epinephrine and
Norepinephrine 709
Dopamine 709
Other Transmitters 709
Role of other Neuroactive Peptides: Large Molecule
Transmitters 711
Applied Physiology 711
Exam-oriented Questions 711
89. Synapse 712
Introduction 712
Classification 712
Anatomical Classification 713
Physiological Classification 713
Anatomical Structure of the Synapse 713
Mechanism of Synaptic Transmission 714
Neuromuscular Junction 715
Excitatory and Inhibitory Postsynaptic Potentials 715
Excitatory Postsynaptic Potential (EPSP) 715
Inhibitory Postsynaptic Potential (IPSP) 715
Properties of Synapse 716
Synaptic Response 716
Law of Forward Conduction (Sherrington) 716
Synaptic Delay 716
Seat of Fatigue 716
Synaptic Inhibitions 716
Convergence and Divergence of Nerve Impulses 717
Synaptic Block 717
Summation 717
Occlusion 718
Ephaptic Transmission 718
Synaptic Plasticity 718
Applied Physiology: Synaptopathy 719
Exam-oriented Questions 719
90. Nerve Endings and Receptors 720
Definition 720
Histology 720
Functions 720
Receptors 720
Receptor as a Biological Transducer 722
Initiation of Impulse in Sensory Receptors 722
Source of Generator Potential 723
Mechanism of Initiation of Generator Potential 723
Properties of Receptors 723
Classification and Varieties of Nerve Endings 724
General Senses 725
Myotactic or Stretch Reflex 727
Mechanism of Stretch Reflex 727
Summary 728
Receptors 728
Motor Endings 728
Exam-oriented Questions 728
91. Reflex Action 929
Definition 729
Varieties of Reflexes 729
Reflex Arc 729
Varieties of Reflex Arc 729
General Characteristics of Reflex Action 730
Irradiation 730
Delay 730
Summation 730
Occlusion 730
Subliminal Fringe 730
Facilitation 730
Inhibition 731
Recruitment 731
After-discharge 732
Fatigue 732
Reciprocal Innervations 732
Rebound Phenomenon 733
Unconditioned Reflexes 733
Classification of Reflexes 733
Superficial Reflexes 733
Deep Reflexes or Tendon Reflexes 734
Patellar Tendon Reflex or Knee Jerk 734
Reflex Path 734
Ankle Jerk 735
Stretch Reflex (Myotatic Reflex) 737
Importance of Stretch Reflex 737
Electrophysiology of Spinal Reflexes 737
Monosynaptic Reflex 737
Polysynaptic Reflex 737
Withdrawal Reflexes 737
Motor Unit and Electromyogram (EMG) 739
EMG 739
Applied Physiology: Startle Reflex 741
Exam-oriented Questions 741
92. Sensory Systems 742
Introduction 742
Sensory Mechanism 742
Properties of Sensations 742
Modality 742
Quality 742
Intensity 742
Adaptation 743
xiContents
xiiHuman Physiology
Extent 743
Duration 744
Localisation or Projection 744
Classification of Sensations 744
General Sensations 744
Pain 746
Theories of Pain 747
Pain Pathway 748
Itch and Tickle 751
Applied Physiology 751
Pain Management 751
Exam-oriented Questions 752
93. Arrangement of Grey and White Matters in the
Spinal Cord 753
Introduction 753
Central Canal 753
Grey Matter 753
White Matter 754
The Spinal Nerve 754
Mixed Nerves 754
Anterior Spinal Root 754
Posterior Spinal Root 754
Distribution of the Terminal Branches of Spinal Nerves 754
Exam-oriented Questions 755
94. The Ascending and Descending Tracts 756
Introduction 756
Definition: Tracts 756
Ascending Tracts (Sensory Tracts) 756
Descending Tracts (Motor Tracts) 757
Ascending Tracts (Afferent Tracts) 757
Afferent Tracts in the Posterior Column (Funiculus) 757
Afferent (Sensory) Tracts in the Lateral Column 759
Afferent (Sensory) Tracts in the Anterior Column 761
Summary of the Pathways of Various Sensations 762
How Posterior Spinal Root Ends? 763
Descending Tracts 765
Motor Tracts or Efferent Tracts 765
Pyramidal or Corticospinal Tracts 765
Corticobulbar (Corticonuclear) Tracts 769
Extrapyramidal Tracts 770
Rubrospinal Tract (Monakow’s Bundle, Prepyramidal
Tract) 770
Tectospinal Tract and Tectobulbar Tract 770
Reticulospinal Tracts 771
Vestibulospinal Tracts 772
Olivospinal Tract (Bulbospinal Tract or Tract of
Helweg) 773
Descending Medial Longitudinal Fasciculus 773
Functions of Extrapyramidal Tracts 773
Intersegmental Fibres (Both Ascending and Descending
Fibres) 773
Effects of Section of the Anterior Root 774
Degenerative Changes 774
Functional Changes 774
Effects of Section of the Posterior Root 774
Degenerative Changes 774
Effects of Section of the Mixed Spinal Nerve 774
Degenerative Changes 774
Functional Changes 774
Hemisection of the Spinal Cord 774
Degenerative Changes 774
Functional Changes 775
Regional Peculiarities of Hemisection of the Spinal
Cord at Different Levels 776
Applied Considerations on Spinal Transections 776
Complete Transection of the Spinal Cord 776
Incomplete Transection of the Spinal Cord 777
Spinal Animal (Animal with Transection of the Spinal
Cord) 777
Effects of Lesions at Various Levels of the Central
Nervous System 777
Lemniscus or Fillet 778
Definition 778
Varieties 778
Exam-oriented Questions 778
95. Brainstem 780
Introduction 780
Midbrain (Mesencephalon) 780
Red Nucleus 781
Connections 781
Characteristic Features of Red Nucleus 782
Functions of Red Nucleus 783
Superior Colliculi 783
Pons Varolii 783
Anatomy 783
Function 784
Medulla Oblongata (Spinal Bulb) 784
Anatomy 784
Function of Medulla Oblongata 785
Exam-oriented Questions 789
96. Cerebellum 790
Anatomy 790
Anatomical Classification 790
Functional and Morphological Subdivision of
Cerebellum 790
Phylogenetic Subdivisions 791
Functional Subdivisions 791
Cerebellar Nuclei 791
Histology 792
Connections 794
Inferior Cerebellar Peduncle (Restiform Body) 794
Middle Cerebellar Peduncle (Brachium Pontis) 795
Superior Cerebellar Peduncle (Brachium
Conjunctivum) 796
Functions of Cerebellum 797
Role of Archicerebellum (via Vestibulocerebellum
and Spinocerebellum Connections) in Maintenance
of Posture and Equilibrium 797
Role of Paleocerebellum (via Spinocerebellar
Connections) in Maintenance of Muscle Tone 797
Role of Neocerebellum in Control of Movements 797
Comparator of a Servomechanism 798
Cerebellum Learning 798
Other Cerebellar Functions 799
Applied Clinical Physiology: Cerebellum 799
Cerebellar Lesions 799
Exam-oriented Questions 800
97. Thalamus 801
Introduction 801
Connections 802
Medial Nuclear Mass 802
Lateral Nuclear Mass 802
Midline Nuclei 803
Intralaminar Nuclei Group 803
Pulvinar Nuclei 803
Functions of the Thalamus 803
Applied Physiology 804
Thalamic Syndrome 804
Prion Disease 804
Exam-oriented Questions 805
98. Mammillary Bodies and Internal Capsule 806
Introduction 806
Internal Capsule 806
Applied Physiology 806
Exam-oriented Questions 806
99. The Basal Ganglia 807
Introduction 807
Characteristics of the Basal Ganglia 807
Interconnections 807
Basal Ganglia Connections of Physiological Importance 808
Corpus Striatum 809
Anatomy 809
Connections of the Corpus Striatum 809
Substantia Nigra 809
Connections of Substantia Nigra 809
Body of Luys or Corpus Luysi (Subthalamic
Nucleus) 809
Functions of the Basal Ganglia 810
Applied Physiology 810
Clinical Manifestations Associated with the Diseases
of the Basal Ganglia 810
Parkinsonism: Paralysis Agitans 810
Progressive Hepatolenticular Degeneration or
Wilson’s Disease 811
Chorea 811
Athetosis 811
Torsion Spasm 811
Hemiballismus or Hemichorea 812
Exam-oriented Questions 812
100. The Reticular Formation 813
Introduction 813
The Ascending Reticular Activating System 813
Wakefulness and Alertness 813
Feedback Theory for the Maintenance of Activation
of the Reticular Activating System 814
Applied Physiology 814
The Descending Reticular System 814
Descending Inhibitory Reticular Projection 815
Descending Facilitatory Reticular Projection 815
Functions of the Reticular Formation 815
Exam-oriented Questions 816
101. Muscle Tone and Posture 817
Introduction 817
Muscle Tone 817
Posture 818
Postural Mechanism 818
Afferent Impulses for Muscle Tone and Posture 818
Higher Centres for Muscle Tone and Posture 818
Thalamic Animal (Vide Functions of Thalamus) 819
Decerebrate Preparation 819
Determination of Posture and Distribution of Muscle
Tone 820
Autogenic Inhibition: Clasp-knife Reflex 821
Midbrain Component 822
Inputs from Vestibular System 822
Flexion Reflexes 822
Spinal Preparation 822
Supraspinal Control of the Stretch Reflex in Relation to
Muscle Tone and Posture 823
Postural Reflexes and Postural Connection 825
Righting Reflexes and Postural Connection 825
Control or Co-ordination of Willed Movement 826
Exam-oriented Questions 827
102. Vestibular Apparatus 828
Introduction 828
Functions of Vestibular Apparatus 830
Vestibular Function Tests 830
The Semicircular Canals 830
Anatomy 830
Histology 831
Mode of Action 833
Functions 833
The Otolithic Organ 833
Anatomy 833
Histology 833
Mode of Action 833
Functions 834
Unilateral Extirpation of the Labyrinths 834
Bilateral Extirpation of the Labyrinths 835
Applied Physiology 835
Exam-oriented Questions 835
103. Path of Vestibular Impulse 836
Introduction 836
Vestibulospinal Tract (from Deiters’ Nucleus) 837
Habituation 837
Exam-oriented Question 837
104. Cerebrum 838
Introduction to Evolution 838
Anatomy 838
Grey Matter (Cortex) 839
White Matter 840
Structure of the Cerebral Cortex and Functions of its
Different Layers 840
Regional Peculiarities 841
Functions of Different Layers of the Cerebral Cortex 843
Functions 843
Localisation of Brain Function 843
Methods of Localisation of Functions in the Cerebral
Cortex 843
Areas and Centres in the Cerebral Cortex 844
Frontal Lobe 844
Precentral Cortex (Areas 4, 6, 8, 44) 844
Prefrontal Cortex (Areas 9, 10, 11, 12, 32) 845
Connections of the Prefrontal Lobes 846
Connections between Different Lobes 846
Functions of the Prefrontal Lobes 846
Applied Physiology: Effects of Removal of the Prefrontal
Lobes 847
Frontal Lobe and the Seat of Intelligence 847
Parietal Lobe 848
Sensory Areas (Areas 3, 1 and 2) 848
Motor Area (Adversive) 848
Temporal Lobe 849
Sensory Area (Auditosensory) 849
Association Area (Auditopsychic) 849
Motor Area (Adversive) 849
Applied Physiology: Temporal lobe Syndrome 849
Occipital Lobe 849
Sensory Area (Visuosensory) 849
Association Area (Visuopsychic) 849
Motor Areas 850
Functions of the Cerebrum 850
Motor Functions 850
Seat of Conditioned Reflex 850
Sensory Functions 850
Intellectual Functions 851
Electrical Activity of the Cerebral Cortex 851
Electroencephalography 851
Applied Physiology: Electroencephalogram (EEG) 851
Electroencephalogram (EEG) 851
Conclusion 855
Physiological Basis of EEG 856
Evoked Cortical Potentials 856
Other Types of Electrical Activity in the Cerebral
Cortex 856
Applied Physiology 857
Brain Death 858
Introduction 858
Exam-oriented Questions 859
xiiiContents
xivHuman Physiology
105. Limbic Lobe and Limbic System 860
Introduction 860
Afferent and Efferent Connections of Limbic System 860
Interconnection 860
Functions of the Limbic System 860
Applied Physiology 861
Exam-oriented Questions 861
106. Speech 862
Introduction 862
Centre 862
Development of Speech 862
Applied Physiology: Aphasia 862
Classification of Aphasia 863
Head’s Classification of Aphasias 864
Exam-oriented Questions 864
107. Neurophysiology of Learning and Memory 865
Introduction 865
Learning 865
Classical Conditioning of Pavlov 865
Development of Conditioned Reflexes 866
Classifications 867
Conditioned Excitatory Reflexes 867
Conditioned Inhibitory Reflexes 867
Functions of Conditioned Reflexes 868
Effects of Drugs upon Conditioned Reflexes 868
Operant Conditioning 868
Condition Avoidance or Avoidance Conditioning 868
Instrumental Conditioning or Learning 868
Discrimination Learning 868
Physiological Basis of Conditioned Reflexes and
Learning 869
Memory and its Neurophysiological Basis 869
Experimental Evaluation: Memory Consolidation and
Storage 870
Mechanism of Memory Encoding, Consolidation and
Storage 870
Applied Physiology 871
Exam-oriented Questions 871
108. Sleep 972
Introduction 872
Sleep Rhythm 872
Sleep Requirement 872
Depth of Sleep 872
Physiological Changes during Sleep 872
Behavioural and EEG Changes during Sleep 873
Types of Sleep 873
Normal Sleep 873
Role of Neuronal System in Sleep-Wakefulness
Cycle 873
Theories of Sleep 874
Feedback Theories of Wakefulness and Sleep 874
Applied Physiology 874
Exam-oriented Questions 875
109. Emotion 876
Introduction 876
Behavioural Changes in Emotion 876
Neural Control of Emotion 876
Hypothalamus 876
Thalamus 877
Cerebral Cortex and Limbic System 877
Papez Circuit: Physiological Basis of Emotion 877
Applied Physiology 878
Exam-oriented Questions 878
110. Cerebrospinal Fluid 879
Introduction 879
Character 879
Composition 879
Formation of Cerebrospinal Fluid 879
Rate of Formation 879
Circulation 880
Nervous and Humoral Factors Controlling the
Formation and Circulation of the Cerebrospinal
Fluid 880
Absorption 880
Mechanism of Absorption 880
Functions of Cerebrospinal Fluid 881
Applied Physiology: Lumbar Puncture 881
Ventriculography 881
Hydrocephalus 881
Blood–CSF and Brain Barrier 881
Blood–Cerebrospinal Fluid Barrier 881
Blood–Brain Barrier 882
Cerebrospinal Fluid–Brain Barrier 882
Exam-oriented Questions 882
111. Autonomic Nervous System 883
Introduction 883
General Considerations 883
General Arrangement 883
Dual Supply 885
Sympathetic (Thoracolumbar) System 885
Sympathetic Ganglia 885
Sympathetic Outflow 886
Gastrointestinal Tract 888
Parasympathetic (Craniosacral) System 888
Parasympathetic Outflow 888
Spinal Parasympathetic 890
Higher Autonomic Centres 891
Functions of Sympathetic and Parasympathetic
Systems 891
Control of the Autonomic Nervous System 893
Nervous Control 893
Applied Physiology 896
Exam-oriented Questions 896
112. Hypothalamus 897
Introduction 897
Nuclei of Hypothalamus 897
Connections of Hypothalamus 897
Afferent Connections 897
Functions of Hypothalamus 899
Controls the Autonomic Nervous System 899
Takes Part in Regulation of Body Temperature 899
Controls Emotions 899
Related to Hunger Feeding, Obesity and Thirst 900
Controls Circadian Rhythm 900
Controls Sleep Wakefulness Cycle 900
Maintenance of Homeostasis 900
Regulation of Water Balance 900
Regulation of Posterior Pituitary Gland Activity 901
Regulation of Pituitary Gland Activity 901
Cardiovascular Regulation 902
Relation with Stress through Neurohormonal
Mediation 902
Applied Physiology 902
Hypopituritarism 902
Common Causes of Hypothalamic Dysfunction 902
Recent Advances 902
Hypothalamus and Odour Response 902
Exam-oriented Questions 903
113. Neurosecretion 904
Introduction 904
Modern Concept of Neurosecretion 904
Nature of Neurosecretory Cells 904
Significance of Neurosecretory Cells 904
Exam-oriented Questions 904
114. Cranial Nerves 905
Introduction 905
Applied Anatomy and Physiology 909
Other Disorders of CNS 909
Exam-oriented Questions 910
Clinical Case Scenario 911
Central Nervous System 911
Section XI Special Senses
115. Senses of Taste 914
Introduction to Special Senses 914
General Characters 914
Taste (Gustation) 914
Primary Taste Sensations 914
Tongue 915
Papillae and Histology of Tongue 915
Taste Buds 915
Histology 915
Distribution 915
Varieties 915
Nature of Stimuli 915
Receptor Stimulation 915
Basic Modalities of Taste 916
Chemical Constitution Related to Taste 916
Threshold of Primary Taste Sensations 916
Factors Influencing Taste Sensations 916
Path of Taste Impulses 917
Applied Physiology 918
Exam-oriented Questions 918
116. Sense of Smell (Olfaction) 919
Introduction 919
Olfactory Mucous Membrane 919
Olfactory Epithelium 919
Olfactory Receptors 920
Olfactory Bulb 921
Olfactometer 921
Physiology of Olfaction 921
Olfactory Discrimination 921
Olfactory Adaptation 922
Chemical Compounds and their Relation to Olfactory
Sensation 922
Relation of Odorous Substances 922
Pathways of Olfactory Impulses 922
Olfactory System: Primitive and New Olfactory
System 922
Pathophysiology of Altered Smell Sensation 923
Exam-oriented Questions 924
117. Physiology of Vision 925
Introduction 925
Tunics 925
Conjunctiva 925
Lacrimal Apparatus 925
Eyeball 926
Refractive Media of the Eyeball 926
Optical Arrangement of the Eye 928
Cornea 928
Functions 928
Histology 928
Nutrition of Cornea 929
Aqueous Humour 929
Composition of Aqueous Humour 929
Flow of Aqueous Humour 930
Functions 930
Aqueous Veins 930
Crystalline Lens 930
Histology 930
Function 931
Nutrition of Lens 931
Vitreous Humour (Vitreous Body) 931
Functions 931
Blood-Vitreous Barrier 932
Control of Eye Movement 932
Co-ordination of Eye Movements 932
Nervous Control 932
Intercommunication of the III, IV and VI Cranial
Nerve Nuclei 933
Effects of Section of III Cranial Nerve 934
Effects of Section of VI Cranial Nerve 935
Effects of Section of IV Cranial Nerve 935
Iris 935
Effects of Sections 936
Functions of Iris 936
Pupil 938
Functions of Pupil 938
Pupillary Reflexes 938
Argyll Robertson Pupil 940
Accommodation 940
Definition 940
Mechanism of Accommodation 940
Nerve Path for Accommodation Reflex 941
Common Errors of Refraction 941
Spherical Aberration 943
Chromatic Aberration 944
Applied Physiology: Contact Lens 944
Advantages of a Contact Lens 944
Retina 944
Anatomy 944
Histology 944
Regional Peculiarities of the Retina 946
Blood Supply of the Retina 947
Functions of the Retina 947
Rods and Cones 947
Fine Structure 947
Formation of an Image on the Retina 950
Effects of Light on the Retina 950
Phototransduction 950
Photochemical Changes 950
Neurophysiology of Vision 951
Electrical Activity in the Retina 951
Electrophysiological Changes 952
Spectral Sensitivity: Scotopic Vision and Photopic
Vision 953
Light and Dark Adaptation 953
Light Adaptation 954
Visual Acuity 954
Snellen’s Test Type 954
Ophthalmoscopy 955
Modern Ophthalmoscope 955
Retinoscopy 955
Field of Vision 955
Definition 955
Extent 955
Mapping of the Field of Vision (Perimetry) 956
xvContents
xviHuman Physiology
B

Nitin Ashok John MD,DIH,FPGDMLE,PGDHA is currently Professor and Head, Department of Physiology,and Dean (Examination),All India Institute of Medical Sciences, Bibinagar, Hyderabad. Earlier, he was Professor and Head, Department of Physiology, Dr Ram Manohar Lohia Institute of Medical Sciences, Lucknow, UP. He did his MBBS from Mahatma Gandhi Institute of Medical Sciences, Sewagram, Wardha, and MD from Indira Gandhi Government Medical College,Nagpur.In addition,he has received the Fellowship from Royal Society of Biology (London), Fellowship from Royal Society of Public Health (London) and Fellowship of Academy of Medical Educators (Cardiff). He has also completed his Post Graduate Diploma in Medical Law and Ethics from NLSU Bangalore, DIH from Annamalai University, Post Graduate Diploma in Hospital Administration from Algappa University and MA in Public Administration from Nagpur University. He has 27 years of standing experience in the medical profession which includes 23 years of experience as faculty and 4 years as medical officer/private practitioner.He has been the UG–PG assessors for Medical Council of India 2011–2019 and is the UG–PG assessor for National Medical Commission, New Delhi, 2019 onwards; President,Association of Physiologists of India,UP Chapter (2019-2020); Finance Secretary,Association of Physiologists of India (2014–2016); and member of various international and national scientific societies. He has conducted and supervised around 30 research projects including 8 funded projects and delivered more than 50 guest lectures at national and international levels at various scientific meetings. He has to his credit over 80 research papers published in national and international journals and written 8 textbooks in physiology. He is dedicated academician,excellent orator,excellent teacher and administrator,as well as author par excellence.

Prof Nitin John took the challenge of editing the eleventh edition to match the prescribed syllabus and twelfth edition of CC Chatterjee’s Human Physiology was brought out in 2018. As the Medical Council of India recommended the Competency Based Curriculum, the thirteenth edition was structured to match the newly designed curriculum. The inputs flowing in from the academicians across the country were taken into consideration and the fourteenth edition of the book has been written as per the Competency Based Curriculum now adopted by National Medical Commission.

Salient Features of the Fourteenth Edition
Text has been simplified and moulded into easy to understand and lucid language for a clear conceptual understanding of the subject.
Recent advances have been added and facts of applied physiology updated throughout the text.
Diagrams have been modified and simplified.
Exam-oriented questions have been introduced to serve the requirements of the students.
A number of new multiple choice questions has been added and others updated.
Topics of exercise physiology, hemoglobin, red blood cells, white blood cells, coagulation, immunity, cardiac output, regulation of blood pressure, hypoxia, regulation of respiration, renal function test, glomerular filtration rate, regulation of body temperature, growth hormones, calcium metabolism, thyroid hormones, adrenal gland, family planning methods, synapses,pain, sleep, hypothalamus,cerebellum,basal ganglia,autonomic function tests,eye and ear have been updated for quick understanding and recapitulation
Applied topics such as diabetes, obesity, pancreatic transplantation, types of exercises, dialysis, family planning methods and disorders associated with central nervous system has been restructured and made concise.
Clinical Case Scenarios,an important component of the latest curriculum adopted by National Medical Commission, shall be immensely helpful in excelling for the candidates preparing for PLAB UK examination, USMLE and examinations of the Medical Councils of the other South East Asian countries.
Historical features and scientific findings have been depicted in the text appropriately.