Physiology for MBBS
Direct answer
Physiology explains how the body works and forms the conceptual base for every clinical subject. In the first professional examination it is tested through theory papers, practical experiments, chart interpretation and viva, and it rewards students who move fluently between a mechanism, its graph, and its clinical application.
What the subject covers in the MBBS curriculum
Under CBME, Physiology is taught through lectures, practicals and demonstrations, integrated with Anatomy and Biochemistry and with early vertical integration with clinical medicine. The syllabus covers general physiology; blood; nerve and muscle; cardiovascular, respiratory, renal, gastrointestinal and endocrine physiology; neurophysiology; special senses; reproductive physiology; and temperature regulation.
High-yield areas for university examinations
- General physiology and nerve-muscle: resting membrane and action potentials; saltatory conduction; neuromuscular junction and its blockers; comparison of skeletal, cardiac and smooth muscle.
- Blood: haemopoiesis and erythropoietin; iron and vitamin B12; coagulation cascade, natural anticoagulants and fibrinolysis; blood grouping and transfusion reactions; platelet function.
- Cardiovascular: cardiac cycle; pacemaker and conducting system; ECG basics and common abnormalities; cardiac output and its regulation; blood pressure regulation including the renin-angiotensin-aldosterone system; shock.
- Respiratory: mechanics of breathing and lung volumes; ventilation-perfusion ratio; oxygen and carbon dioxide transport; cyanosis and hypoxia; control of respiration; high-altitude physiology.
- Renal: glomerular filtration and its regulation; clearance; tubular transport; counter-current mechanism; acid-base handling; micturition.
- Gastrointestinal and endocrine: GI secretions and motility; hypothalamo-pituitary axis; thyroid; adrenal cortex and medulla; insulin and glucagon; calcium homeostasis; menstrual cycle and pregnancy tests.
- Neurophysiology and special senses: synapse and receptors; ascending and descending tracts; reflexes; cerebellum and basal ganglia; EEG and sleep; refraction errors and visual field defects; hearing and balance.
- Integrative topics: temperature regulation, exercise physiology and body fluid compartments — frequent short-essay favourites.
Theory preparation
Structure long answers as a physiological story: definition, mechanism step by step, a labelled graph or flow chart, regulation, and clinical correlation. Diagrams that repeatedly earn marks include cardiac cycle curves, the spirogram, the nephron with transport sites, the action potential with ionic changes, the menstrual cycle chart and thyroid hormone synthesis. For short answers, write the key value or decisive mechanism first, then explain. Maintain a master list of normal values — heart rate, cardiac output, GFR, lung volumes, blood counts — and revise it weekly.
Practicals and viva
The practical examination usually includes haematology experiments (haemoglobin, red cell and leucocyte counts, erythrocyte sedimentation rate, packed cell volume and indices, platelet count, bleeding and clotting time, blood grouping), clinical physiology (pulse, blood pressure, ECG recording, spirometry), clinical examinations of the cardiovascular, respiratory and nervous systems, demonstrated experiments and chart interpretation. For every chart — ECG, spirogram, glucose tolerance test, hormone profile — practise reading it aloud: title, axes and normal values, abnormality, and one mechanism. Viva often starts from your own experiment, so know the principle, sources of error and clinical importance of each test.
Preparation with PrepElephant
The PrepElephant app supports Physiology with previous-year-question-based practice, question banks, revision checklists and viva preparation, letting you test each system after studying it. Free notes on this website, including topic pages on the cardiac cycle and renal clearance, follow a direct-answer format that mirrors a good viva answer.
Frequently asked questions
Which topics are asked most often?
Cardiac cycle, blood pressure regulation, ECG, lung volumes and gas transport, glomerular filtration and the counter-current mechanism, action potential, coagulation, thyroid and insulin physiology, and the menstrual cycle recur across universities.
How should I prepare charts for the practical exam?
Learn each chart in a fixed pattern — title and axes, normal values, how the curve is produced, what shifts it, and one clinical example. Examiners often hand you an unlabelled ECG or spirogram.
What normal values must I know?
Core values include heart rate 60–100 per minute, cardiac output about 5 litres per minute, GFR about 125 ml per minute, tidal volume about 500 ml, and haemoglobin about 13–17 g/dL in adult men and 12–15 g/dL in adult women. Quote the set your university follows.
How much Biochemistry overlap is there?
Considerable — metabolism, hormones, vitamins and body fluids. Studying integrated topics together, such as insulin with carbohydrate metabolism, saves time and strengthens both subjects.
How is the Physiology viva conducted?
It usually begins with your experiment or chart, extends to its principle and clinical application, and ends with rapid short questions from theory. Definition, mechanism, one correlation is a reliable pattern.
Does PrepElephant help with Physiology practicals?
The app offers PYQ-based practice, question banks, revision checklists and viva preparation covering theory and practical-oriented questions; hands-on experiments must be learned in your laboratory.
Practise this in the PrepElephant app
Question banks, previous-year questions, mock tests and revision tools — for Physiology for MBBS. Free to start.