CSIR-NET LIFE SCIENCES

Unit 7: System Physiology – Animal

Complete Topic-Wise Syllabus

Blood & Circulation • Cardiovascular System • Respiration • Nervous System • Sense Organs • Excretion • Thermoregulation • Stress • Digestion • Endocrinology • Microbiome • Energy Homeostasis

A. Blood and Circulation

🩸 1. Blood and Its Components

• Composition of blood
• Blood cells
• Plasma
• Red blood cells
• White blood cells
• Platelets
• Plasma proteins
• Electrolytes
• Nutrients and metabolites

🔴 2. Blood Corpuscles

• Erythrocytes
• Leukocytes
• Platelets
• Structure and function of RBCs
• Types of WBCs
• Neutrophils
• Eosinophils
• Basophils
• Monocytes
• Lymphocytes

🧬 3. Haemopoiesis

• Formation of blood cells
• Hematopoietic stem cells
• Bone marrow
• Myeloid lineage
• Lymphoid lineage
• Erythropoiesis
• Leukopoiesis
• Thrombopoiesis
• Role of erythropoietin

💧 4. Plasma Functions

• Transport
• Osmotic regulation
• Acid-base balance
• Protein transport
• Hormone transport
• Immune functions
• Blood clotting

📊 5. Blood Volume Regulation

• Normal blood volume
• Fluid balance
• Plasma volume
• Role of kidney
• Role of ADH
• Role of aldosterone
• Role of renin-angiotensin system

🩸 6. Blood Groups

• ABO blood group system
• Rh blood group system
• Antigens
• Antibodies
• Blood transfusion
• Hemolytic disease

🫁 7. Haemoglobin

• Structure of hemoglobin
• Heme group
• Oxygen binding
• Oxygen dissociation curve
• Bohr effect
• Cooperative binding
• Carbon dioxide transport
• Carbaminohemoglobin

🛡️ 8. Immunity

• Innate immunity
• Adaptive immunity
• Leukocyte functions
• Antibodies
• Complement system
• Inflammatory responses

🩹 9. Haemostasis

• Vascular response
• Platelet plug formation
• Blood coagulation
• Intrinsic pathway
• Extrinsic pathway
• Common pathway
• Thrombin
• Fibrin formation
• Fibrinolysis

🎯 Hemostasis Sequence:

Vascular injury → Vasoconstriction → Platelet plug → Coagulation cascade → Thrombin → Fibrinogen → Fibrin → Stable clot

B. Cardiovascular System

❤️ 1. Comparative Anatomy of Heart

• Fish heart
• Amphibian heart
• Reptilian heart
• Avian heart
• Mammalian heart
• Evolution of cardiac chambers

❤️ 2. Mammalian Heart Structure

• Atria
• Ventricles
• Valves
• Septum
• Coronary circulation
• Major blood vessels

⚡ 3. Myogenic Heart

• Intrinsic cardiac activity
• Pacemaker cells
• Sinoatrial node
• Atrioventricular node
• Bundle of His
• Purkinje fibers

📈 4. ECG

• Principle of electrocardiography
• P wave
• QRS complex
• T wave
• Electrical activity of heart
• Clinical significance of ECG

❤️ ECG Quick Revision:

P wave → Atrial depolarization
QRS complex → Ventricular depolarization
T wave → Ventricular repolarization

🔄 5. Cardiac Cycle

• Atrial systole
• Ventricular systole
• Diastole
• Heart sounds
• Valve movements
• Stroke volume
• Cardiac output

💓 6. Heart as a Pump

• Cardiac output
• Heart rate
• Stroke volume
• Preload
• Afterload
• Contractility

🩺 7. Blood Pressure

• Systolic pressure
• Diastolic pressure
• Mean arterial pressure
• Pulse pressure
• Peripheral resistance

🧠 8. Regulation of Cardiovascular System

• Autonomic nervous system
• Sympathetic regulation
• Parasympathetic regulation
• Baroreceptor reflex
• Chemoreceptor reflex
• Hormonal regulation
• Renin-angiotensin-aldosterone system
• Adrenaline and noradrenaline

C. Respiratory System

🫁 1. Comparative Respiration

• Respiration in aquatic animals
• Respiration in terrestrial animals
• Gills
• Tracheal system
• Skin respiration
• Lungs
• Comparative respiratory adaptations

🫁 2. Respiratory Anatomy

• Nasal cavity
• Pharynx
• Larynx
• Trachea
• Bronchi
• Bronchioles
• Alveoli
• Pulmonary circulation

🌬️ 3. Transport of Gases

• Oxygen transport
• Hemoglobin
• Oxygen dissociation curve
• Carbon dioxide transport
• Bicarbonate formation
• Carbaminohemoglobin
• Chloride shift

🔄 4. Gas Exchange

• Diffusion
• Partial pressure
• Alveolar gas exchange
• Ventilation-perfusion relationship
• Factors affecting gas exchange

🧠 5. Neural Regulation

• Respiratory centers
• Medulla
• Pons
• Chemoreceptors
• Central chemoreceptors
• Peripheral chemoreceptors

⚗️ 6. Chemical Regulation

• CO₂ regulation
• O₂ regulation
• Blood pH
• Carbon dioxide sensing
• Respiratory response to hypoxia

♻️ 7. Waste Elimination

• CO₂ elimination
• Water vapor loss
• Volatile substances

D. Nervous System

🧠 1. Neurons

• Neuron structure
• Cell body
• Dendrites
• Axon
• Myelin sheath
• Nodes of Ranvier

⚡ 2. Action Potential

• Resting membrane potential
• Depolarization
• Repolarization
• Hyperpolarization
• Voltage-gated Na⁺ channels
• Voltage-gated K⁺ channels
• Refractory period
• Saltatory conduction

⚡ Action Potential:

Resting state → Na⁺ channel opening → Depolarization → Na⁺ channel inactivation → K⁺ channel opening → Repolarization → Hyperpolarization → Resting state

🧠 3. Brain Organization

• Cerebrum
• Cerebellum
• Brainstem
• Hypothalamus
• Thalamus
• Medulla oblongata
• Pons
• Midbrain

🧬 4. Spinal Cord

• Gray matter
• White matter
• Dorsal root
• Ventral root
• Spinal nerves
• Reflex arcs

🔌 5. Central and Peripheral Nervous System

• CNS
• PNS
• Somatic nervous system
• Autonomic nervous system
• Sympathetic nervous system
• Parasympathetic nervous system

💪 6. Neural Control of Muscle

• Neuromuscular junction
• Acetylcholine
• Motor units
• Muscle tone
• Posture
• Spinal reflexes
• Motor control

E. Sense Organs

👁️ 1. Vision

• Eye structure
• Retina
• Rods
• Cones
• Photopigments
• Phototransduction
• Visual pathway
• Color vision
• Dark adaptation

👂 2. Hearing

• External ear
• Middle ear
• Inner ear
• Cochlea
• Organ of Corti
• Hair cells
• Auditory transduction
• Auditory pathway

✋ 3. Tactile Responses

• Touch receptors
• Pressure receptors
• Pain receptors
• Temperature receptors
• Mechanoreceptors
• Nociceptors
• Somatosensory pathways

👁️👂 Sense Organ Principle:

Environmental stimulus → Receptor activation → Electrical signal → Sensory neuron → CNS → Perception/response

F. Excretory System

♻️ 1. Comparative Excretion

• Ammonotelic animals
• Ureotelic animals
• Uricotelic animals
• Ammonia excretion
• Urea excretion
• Uric acid excretion

🫘 2. Kidney Structure

• Nephron
• Glomerulus
• Bowman's capsule
• Proximal tubule
• Loop of Henle
• Distal tubule
• Collecting duct

💧 3. Urine Formation

• Glomerular filtration
• Tubular reabsorption
• Tubular secretion
• Urine formation
• Renal clearance

🧂 4. Urine Concentration

• Counter-current mechanism
• Loop of Henle
• Vasa recta
• Medullary osmotic gradient
• ADH
• Water reabsorption

🚰 5. Water Balance

• Osmoregulation
• ADH
• Thirst mechanism
• Kidney function
• Osmoreceptors

🩺 6. Blood Pressure Regulation

• Renin
• Angiotensin
• Aldosterone
• Renin-angiotensin-aldosterone system
• Kidney-mediated blood pressure regulation

🧂 7. Electrolyte Balance

• Sodium
• Potassium
• Calcium
• Chloride
• Phosphate
• Electrolyte homeostasis

⚗️ 8. Acid-Base Balance

• Bicarbonate buffer
• H⁺ secretion
• Renal bicarbonate reabsorption
• Ammonium excretion
• Respiratory and renal regulation

🚻 9. Micturition

• Urinary bladder
• Detrusor muscle
• Internal sphincter
• External sphincter
• Micturition reflex
• Neural control

🎯 Urine Formation:

Filtration → Reabsorption → Secretion → Excretion

G. Thermoregulation

🌡️ 1. Body Temperature

• Core temperature
• Peripheral temperature
• Homeothermy
• Poikilothermy
• Endothermy
• Ectothermy

🌡️ 2. Comfort Zone

• Thermoneutral zone
• Environmental temperature
• Heat production
• Heat loss

🔥 3. Physical Regulation

• Radiation
• Conduction
• Convection
• Evaporation

⚡ 4. Chemical Regulation

• Metabolic heat production
• Shivering
• Non-shivering thermogenesis
• Brown adipose tissue
• Thyroid hormones

🧠 5. Neural Regulation

• Hypothalamus
• Thermoreceptors
• Heat-loss center
• Heat-production mechanisms
• Behavioral responses

🌍 6. Acclimatization

• Adaptation to heat
• Adaptation to cold
• Changes in sweating
• Changes in blood flow
• Metabolic adjustments

H. Stress and Adaptation

⚠️ 1. Stress

• Physiological stress
• Environmental stress
• Psychological stress
• Physical stress

🧠 2. Stress Response

• Hypothalamus
• Pituitary gland
• Adrenal gland
• HPA axis
• Cortisol
• Adrenaline

🔄 3. Adaptation

• Acclimation
• Acclimatization
• Physiological adaptation
• Behavioral adaptation
• Homeostatic responses

🧠 HPA Axis:

Hypothalamus → CRH → Pituitary → ACTH → Adrenal cortex → Cortisol

I. Digestive System

🍽️ 1. Digestion

• Ingestion
• Mechanical digestion
• Chemical digestion
• Gastrointestinal tract
• Digestive enzymes

🧪 2. Carbohydrate Digestion

• Salivary amylase
• Pancreatic amylase
• Disaccharidases
• Monosaccharide absorption

🥩 3. Protein Digestion

• Pepsin
• Trypsin
• Chymotrypsin
• Peptidases
• Amino acid absorption

🥑 4. Lipid Digestion

• Bile salts
• Emulsification
• Pancreatic lipase
• Micelle formation
• Fatty acid absorption
• Chylomicron formation

🚚 5. Absorption

• Small intestine
• Villi
• Microvilli
• Glucose transport
• Amino acid transport
• Lipid absorption
• Vitamin absorption

⚡ 6. Energy Balance

• Energy intake
• Energy expenditure
• Storage of energy
• Adipose tissue
• Metabolic regulation

🔥 7. Basal Metabolic Rate

• BMR definition
• Factors affecting BMR
• Age
• Sex
• Body composition
• Thyroid hormones
• Environmental temperature

J. Endocrinology and Reproduction

🧪 1. Endocrine Glands

• Hypothalamus
• Pituitary gland
• Thyroid gland
• Parathyroid glands
• Adrenal glands
• Pancreas
• Pineal gland
• Gonads

⚙️ 2. Mechanisms of Hormone Action

• Peptide hormones
• Steroid hormones
• Membrane receptors
• Intracellular receptors
• Second messengers
• cAMP pathway
• IP₃/DAG pathway
• Protein kinase signaling
• Gene regulation

🧬 3. Major Hormones

• Growth hormone
• Prolactin
• TSH
• ACTH
• FSH
• LH
• Insulin
• Glucagon
• Thyroxine
• Cortisol
• Aldosterone
• Adrenaline

🩺 4. Hormones and Diseases

• Diabetes mellitus
• Hypothyroidism
• Hyperthyroidism
• Cushing syndrome
• Addison disease
• Growth hormone disorders

♂️ 5. Male Reproduction

• Testis
• Spermatogenesis
• Sertoli cells
• Leydig cells
• Testosterone
• Androgen regulation

♀️ 6. Female Reproduction

• Ovary
• Oogenesis
• Follicular development
• Estrogen
• Progesterone
• Ovulation
• Corpus luteum

🔄 7. Reproductive Regulation

• Hypothalamic-pituitary-gonadal axis
• GnRH
• FSH
• LH
• Sex steroid feedback
• Menstrual/estrous cycle

♂️♀️ HPG Axis:

Hypothalamus → GnRH → Pituitary → FSH/LH → Gonads → Sex hormones → Feedback regulation

K. Concept of Metaorganisms / Holobionts

🦠 1. Metaorganism Concept

• Host organism + associated microorganisms
• Microbiota
• Microbiome
• Holobiont
• Host-microbe interactions
• Microbial metabolites

🦠 2. Gut Microbiome

• Composition of gut microbiota
• Bacterial diversity
• Gut microbial communities
• Microbial metabolites
• Short-chain fatty acids
• Vitamin production
• Immune regulation

🔬 3. Study of Gut Microbiome

• 16S rRNA sequencing
• Metagenomics
• Metatranscriptomics
• Metabolomics
• Microbiome diversity
• Alpha diversity
• Beta diversity

🧫 4. Germ-Free Animals

• Definition of germ-free animals
• Gnotobiotic animals
• Microbiome transplantation
• Role of microbiota in development
• Role of microbiota in immunity

🧠 5. Gut-Brain Axis

• Bidirectional gut-brain communication
• Neural signaling
• Hormonal signaling
• Immune signaling
• Microbial metabolites
• Neurotransmitter-related signaling

⚠️ 6. Dysbiosis

• Alteration of gut microbial composition
• Loss of microbial diversity
• Inflammation
• Metabolic disorders
• Immune disorders
• Gut barrier dysfunction

🩺 7. Microbiome and Disease

• Obesity
• Diabetes
• Inflammatory disorders
• Gastrointestinal diseases
• Immune-related diseases
• Neurological associations

🦠 Holobiont Concept:

Host + Microbiota + Microbial genes + Microbial metabolites = Integrated biological system

L. Interorgan Communication and Energy Homeostasis

🔄 1. Interorgan Communication

• Communication between organs
• Hormonal signals
• Neural signals
• Metabolic signals
• Cytokines
• Adipokines
• Myokines
• Hepatokines

🍽️ 2. Energy Homeostasis

• Energy intake
• Energy expenditure
• Energy storage
• Glucose homeostasis
• Lipid homeostasis
• Appetite regulation
• Satiety

🧠 3. Brain Control of Energy Balance

• Hypothalamus
• Appetite control
• Leptin
• Ghrelin
• Insulin signaling
• Satiety signals

🍬 4. Glucose Homeostasis

• Insulin
• Glucagon
• Glycogenesis
• Glycogenolysis
• Gluconeogenesis
• Glucose uptake

🥑 5. Lipid Homeostasis

• Lipogenesis
• Lipolysis
• Fat storage
• Fat mobilization
• Adipose tissue signaling

⚠️ 6. Metabolic Disorders

• Obesity
• Insulin resistance
• Type 2 diabetes
• Metabolic syndrome
• Dyslipidemia
• Fatty liver disease

🔥 Energy Homeostasis:

Food intake → Nutrient absorption → Metabolism → Energy production → Energy storage ↔ Energy expenditure

Major regulators include insulin, glucagon, leptin, ghrelin and hypothalamic pathways.

📚 Unit 7 – Animal Physiology Quick Revision Map

A → Blood & Circulation

B → Cardiovascular System

C → Respiratory System

D → Nervous System

E → Sense Organs

F → Excretory System

G → Thermoregulation

H → Stress & Adaptation

I → Digestive System

J → Endocrinology & Reproduction

K → Metaorganisms & Holobionts

L → Energy Homeostasis

🎯 Most Important CSIR-NET Topics

• Blood cells and haemopoiesis
• Hemoglobin and oxygen dissociation curve
• Bohr effect
• ABO and Rh blood groups
• Hemostasis and coagulation cascade
• Cardiac cycle
• ECG and its interpretation
• Cardiac output
• Blood pressure regulation
• Baroreceptor reflex
• Respiratory gas exchange
• Oxygen and CO₂ transport
• Chloride shift
• Respiratory regulation
• Action potential
• Saltatory conduction
• Synaptic transmission
• Brain and spinal cord organization
• Autonomic nervous system
• Phototransduction
• Auditory transduction
• Nephron structure and function
• Glomerular filtration
• Counter-current mechanism
• ADH and water balance
• Renin-angiotensin-aldosterone system
• Acid-base balance
• Thermoregulation
• HPA axis
• Digestive enzymes
• Nutrient absorption
• Basal metabolic rate
• Endocrine signaling
• Second messenger systems
• HPG axis
• Gametogenesis and ovulation
• Gut microbiome
• Germ-free animals
• Gut-brain axis
• Dysbiosis
• Interorgan signaling
• Insulin and glucagon
• Leptin and ghrelin
• Energy homeostasis
• Metabolic syndrome

📖 Recommended Study Sequence:

🩸 Blood → ❤️ Cardiovascular → 🫁 Respiration → 🧠 Nervous System → 👁️ Sense Organs → 🫘 Excretion → 🌡️ Thermoregulation → ⚠️ Stress → 🍽️ Digestion → 🧪 Endocrinology → 🦠 Microbiome → 🔥 Energy Homeostasis