Questions
10–12 questions in NEET/CUET
Difficulty
Medium-Hard
Importance
Core high-yield topic with 20% weightage in Biology section
Overview
Human Physiology is a cornerstone of the biological sciences curriculum, focusing on the functional integration of organ systems to maintain homeostasis. It is a high-yield topic for competitive exams like NEET and CUET, requiring a deep understanding of metabolic pathways, gas exchange mechanisms, and hormonal feedback loops.
Digestion and Absorption
This section covers the enzymatic breakdown of macromolecules and their subsequent transport into the circulatory system. Focus on the chemical nature of digestive juices and the specific sites of absorption for different nutrients.
- Proteins: Pepsin in stomach, Trypsin/Chymotrypsin in small intestine
- Emulsification of fats by bile salts
- Absorption of glucose and amino acids via facilitated diffusion/Na+ coupled transport
- Chylomicrons transport fatty acids into lacteals
Breathing and Respiration
Master the physical mechanism of pulmonary ventilation and the chemical regulation of oxygen-hemoglobin dissociation. Questions often test the shift in the dissociation curve due to pH and CO2 levels (Bohr effect).
- Tidal volume: ~500 mL
- Oxyhemoglobin dissociation curve: Sigmoid shape
- Bohr effect: Right shift due to increased pCO2, H+, and temperature
- Haldane effect: Deoxygenated blood facilitates CO2 transport
Body Fluids and Circulation
Understand the cardiac cycle, the electrical conduction system of the heart, and blood clotting factors. Pay close attention to the P-QRS-T wave intervals in an ECG as these are frequently used in analytical problems.
- Cardiac output = Stroke volume x Heart rate
- Double circulation: Pulmonary and Systemic loops
- Intrinsic conduction: SA node to AV node to Bundle of His to Purkinje fibers
- Clotting factors: Fibrinogen to Fibrin via Thrombin
Excretory Products and Elimination
Focus on the functional unit of the kidney, the nephron, specifically the counter-current mechanism. This is a favorite area for complex multi-concept questions involving fluid osmolality.
- Glomerular Filtration Rate (GFR): ~125 mL/min
- Counter-current multiplier: Maintains medullary interstitial gradient
- ADH/Vasopressin: Increases water reabsorption in DCT and collecting duct
- Renin-Angiotensin-Aldosterone System (RAAS) regulates BP
Chemical Coordination
Study the endocrine system's role in long-distance signaling and metabolic regulation. Focus on the specific mechanisms of peptide versus steroid hormone action on target cells.
- Hypothalamus: Releasing and inhibiting hormones
- Peptide hormones: Act via second messengers (cAMP, IP3)
- Steroid hormones: Bind to intracellular receptors to regulate gene expression
- Negative feedback loops: Basis of thyroid and adrenal control
Exam Tip
Focus heavily on diagrams and flowcharts for metabolic and circulatory pathways, as many questions require visual identification of physiological stages.
Common Mistakes
- Confusing the direction of the Bohr shift (Right shift means decreased affinity for O2).
- Misinterpreting GFR values and filtration pressures in the renal corpuscle.
- Ignoring the distinction between peptide and steroid hormone signaling pathways.
More Revision Notes
Ready to test yourself?
Play topic-wise Human Physiology questions in Aspirant Arcade — gamified MCQ practice.
Download Free