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DNB Physiology Previous Year Questions

These are the DNB Physiology theory questions asked by NBEMS in the December 2025 and June 2025 exams, listed paper by paper as they appeared. The Prep DNB app has all 17 DNB sessions from December 2014 to December 2025 — 670 questions in total — with repeat-question tracking, examiner keywords and MCQs.

Jump to: December 2025 · June 2025 · Important topics · Older papers

DNB Physiology December 2025 Question Paper

Paper 1

  1. Osmolar movement in oedematous and inflammatory disorders: a) Definition of osmolarity, tonicity and effective osmoles. [3] b) Explain the physiological basis of cell swelling and shrinkage. [4] c) Describe clinical applications of concepts of osmolality in intravenous fluid therapy. [3]
  2. Ion transport in cellular electrophysiology & pathophysiology: a) Explain the Nernst equation and its assumptions. [3] b) Describe Goldman-Hodgkin-Katz equation in detail. [4] c) Give the limitations of Nernst and Goldman-Hodgkin-Katz equations. [3]
  3. Voltage-gated Na+ channel in cardiac & muscular diseases: a) Structure of voltage-gated Na+ channels. [3] b) Activation and inactivation mechanisms of voltage-gated Na+ channels. [4] c) Discuss Na+ channel-related genetic channelopathies. [3]
  4. Structural muscle contraction: a) Describe structural organization of skeletal muscle fibres. [3] b) Explain cross-bridge cycling with ATPase activity. [4] c) Genetic disorders affecting contractile proteins. [3]
  5. Cellular junction & intercellular transport: a) Define cell junctions and their types. [3] b) Explain molecular composition and functions of tight junctions. [4] c) Discuss diseases related to junctional defects. [3]
  6. a) Define second messengers. [2] b) Explain cAMP and IP3-DAG pathways. [4] c) Describe genetic mutations affecting second messenger pathways. [4]
  7. a) Describe the functions of the cytoskeleton. [2] b) Explain the structure and functions of microtubules, microfilaments and intermediate filaments. [6] c) Discuss the clinical disorders related to cytoskeleton defects. [2]
  8. a) Explain DNA replication initiation. [3] b) Describe leading and lagging strand synthesis. [4] c) Discuss telomere maintenance. [3]
  9. a) Discuss the historical development of genetics. [3] b) Explain the central dogma including exceptions. [4] c) Describe role of non-coding RNAs in gene regulation. [3]
  10. a) Describe DNA repair mechanisms. [3] b) Explain mismatch repair and its molecular basis. [4] c) Give the clinical relevance of defective repair systems. [3]

Paper 2

  1. a) Define cardiac output and discuss Fick principle. [3] b) Explain the factors regulating stroke volume. [4] c) Compare fetal vs adult cardiac output distribution. [3]
  2. a) Describe determinants of blood flow (Poiseuilles law). [3] b) Explain the mechanism of autoregulation of blood flow. [4] c) Compare laminar vs turbulent flow. [3]
  3. a) Discuss structure & function of RBC membrane. [3] b) Explain the factors affecting oxygen transport mechanism by hemoglobin. [4] c) Describe differences between fetal hemoglobin and adult hemoglobin. [3]
  4. a) Describe migrating motor complex. [3] b) Explain the mechanism of gastric acid secretion. [4] c) Discuss the pathophysiology of gastric ulcers. [3]
  5. a) Describe the various determinants of GFR. [3] b) Explain the countercurrent mechanism in nephron. [4] c) Add a note on urea cycling. [3]
  6. a) Describe lung compliance & hysteresis. [3] b) Explain ventilation-perfusion ratio. [4] c) Discuss the various pressure-volume changes in the alveoli and pleural space during respiration. [3]
  7. a) Innervation of urinary bladder. [3] b) Micturition reflex and cystometrogram in normal human. [4] c) Explain the effects of deafferentation, denervation and spinal cord transection on urinary bladder functioning. [3]
  8. a) Enterohepatic circulation. [3] b) Mechanism of absorption and metabolism of fats. [4] c) Role of dietary fibres. [3]
  9. a) Describe platelet activation pathways. [3] b) Explain the mechanism of coagulation. [4] c) Use of anticoagulants in various clinical conditions. [3]
  10. a) Describe the role of J receptors present in lungs. [3] b) Explain the mechanism of neural control of respiration. [4] c) Describe the various non-chemical stimuli / afferents affecting the respiratory centre. [3]

Paper 3

  1. a) Describe folliculogenesis. [3] b) Explain hormonal control of ovarian and endometrial cycle. [4] c) Discuss pathophysiology of anovulatory cycles. [3]
  2. a) Describe placental transport mechanisms. [3] b) Explain fetal circulation shunts. [4] c) Discuss causes of fetal growth restriction. [3]
  3. a) Describe sarcomere and sarco-tubular system. [3] b) Compare the mechanism of muscle contraction in skeletal and smooth muscle. [4] c) Discuss pathophysiology of Lambert Eaton syndrome. [3]
  4. a) Describe portal circulation of pituitary. [3] b) Regulation of growth hormone secretion. [4] c) Discuss the pathophysiology of acromegaly. [3]
  5. a) Describe thyroid hormone synthesis. [3] b) Explain the various thyroid function tests and the regulation of thyroid hormone synthesis. [4] c) Discuss Graves' disease. [3]
  6. a) Describe the various hearing tests. Differentiate between air conduction and nerve conduction types of deafness. [4] b) Explain mechanisms of sound transduction. [4] c) Discuss pathophysiology of Meniere's disease. [2]
  7. a) Describe types of brain waves. [3] b) Explain physiological basis of EEG generation. [4] c) Discuss the various neurotransmitters involved in sleep and wakefulness. [3]
  8. a) Describe nuclei of hypothalamus. [3] b) Explain the mechanism of temperature regulation. [4] c) Discuss the pathophysiology of fever. [3]
  9. a) Describe the dorsal column system. [3] b) Explain pain modulation pathways. [4] c) Discuss neuropathic pain. [3]
  10. a) Describe sympathetic outflow. [3] b) Explain mechanisms of neurotransmitter release at ANS synapses. [4] c) Discuss autonomic dysreflexia. [3]

Paper 4

  1. a) Define mean arterial pressure and its determinants. [3] b) Explain physiological basis of measuring blood pressure using oscillometric method. [4] c) Mention recent advances in wearable blood pressure monitoring. [3]
  2. a) Define renal plasma flow. [2] b) Explain the role of clearance of PAH in measuring RPF and creatinine in measuring GFR. [5] c) Name two modern imaging modalities estimating renal perfusion. [3]
  3. a) Define evoked potentials. [2] b) Explain the physiology of sensory evoked potential. [5] c) Mention two recent clinical uses of evoked potentials. [3]
  4. a) Define VO2 max. [2] b) Explain cardiovascular adaptations to endurance training. [5] c) Modern tools for home-based exercise monitoring. [3]
  5. a) Define gastric emptying time. [2] b) Explain factors affecting gastric emptying. [5] c) Recent advances in gastric motility monitoring. [3]
  6. a) Define acclimatization. [2] b) Discuss the various cardio-respiratory responses during high altitude exposure. [5] c) Mention any two recent prophylactic strategies for acute mountain sickness. [3]
  7. a) Define circadian rhythm. [2] b) Explain physiology of REM and NREM sleep. [5] c) State two modern tools for sleep monitoring. [3]
  8. a) Define Heart Rate variability (HRV). Describe various time domain parameters of HRV. [3] b) Physiology of sympathetic and parasympathetic effects on HR. [4] c) Name two modern HRV-based clinical uses. [3]
  9. a) Describe the process of innate immunity. [3] b) Explain role of cytokines in inflammation. [4] c) Mention modern cytokine measurement tools. [3]
  10. a) Define sarcopenia. [3] b) Explain mechanisms of age-related muscle loss. [4] c) Mention recent advances in monitoring muscle mass. [3]

DNB Physiology June 2025 Question Paper

Paper 1

  1. a) Discuss the basic structure of the cell membrane. [4] b) Add a note on the membrane glycoproteins. [4] c) Add a note on cell glycocalyx. [2]
  2. a) What is positive feedback control system. [2] b) Discuss its role in health and disease. [6] c) Add a note on feed forward and adaptive control mechanisms. [2]
  3. Describe the mechanism of Potassium homeostasis. [10]
  4. a) Micro RNA (miRNA) and Small interfering RNA (siRNA)'. [4] b) Role of promoter in control of gene expression. [3] c) Stem cells. [3]
  5. a) Contribution of William Einthoven in the field of Cardiology. [3] b) Contribution of Robert F. Furchgott. [3] c) Cilia and ciliary movements. [4]
  6. a) Secondary active transport mechanisms. [4] b) Gap junctions. [3] c) Patch clamp technique. [3]
  7. a) List the major theories of aging in humans and elaborate any two. [8] b) What is the 'Blue Zone' phenomenon? [2]
  8. a) Physio-clinical significance of Molecular motors. [3] b) Physio-clinical significance of JAK-STAT pathway. [3] c) Physio-clinical significance of Acute Phase Proteins. [4]
  9. a) Discuss the physiological basis of the genesis and propagation of action potential in nerve fibers. [7] b) Add a note on phenomenon of plateau in some action potentials. [3]
  10. a) Implementation of Self-Directed Learning in Phase 1 MBBS students. [5] b) ANOVA. [5]

Paper 2

  1. a) Describe mechanism of erythroblastosis fetalis. [3] b) Describe clinical features of erythroblastosis fetalis. [3] c) Discuss physiological basis of prevention and treatment of erythroblastosis fetalis. [4]
  2. a) Discuss the effects of bronchial asthma on lung mechanics and lung functions. [5] b) Discuss the effects of pulmonary fibrosis on lung mechanics and lung functions. [5]
  3. a) Describe the various types of motility patterns observed in gastrointestinal tract. [8] b) Add a note on Achalasia cardia. [2]
  4. a) Urinary buffers. [3] b) Thalassemia. [3] c) Pulse wave analysis. [4]
  5. a) Discuss the physiological basis of the circulatory dynamics in compensated heart failure. [4] b) Discuss the physiological basis of the circulatory dynamics in decompensated heart failure. [4] c) Add a note on mechanism of action of cardiotonic drugs. [2]
  6. a) Cardiovascular responses in isometric and isotonic exercise. [4] b) Static and dynamic lung compliance. [3] c) Hypoxic and histotoxic hypoxia. [3]
  7. a) Discuss the physiological basis of growth and development. [6] b) Draw a normal growth chart in humans and explain the various phases. [4]
  8. a) Physio-clinical significance of Reticulocyte response. [3] b) Physio-clinical significance of Baroreflex sensitivity. [3] c) Physio-clinical significance of Gut brain axis. [4]
  9. a) Discuss the role of kidney in regulating the acid base balance. [8] b) What is anion gap? [2]
  10. a) Autologous transfusion. [4] b) Interstitial cells of Cajal. [3] c) Activated plasma thromboplastin time. [3]

Paper 3

  1. a) Describe the mechanism of transmission and perception of pain. [6] b) Add a note on central analgesia system. [4]
  2. Discuss the interplay of cerebellum and basal ganglia in regulating movement. [5+5]
  3. a) Describe the sequence of physiological events associated with occurrence of ovulation. [6] b) Add a note on feedback regulation of hypothalamic-pituitary-ovarian axis in females. [4]
  4. a) Cryptorchidism. [3] b) Bone remodeling. [3] c) Heat stroke. [4]
  5. a) Describe the regulation of secretion of glucocorticoids. [4] b) Add a note on their physiological actions. [6]
  6. a) Decerebrate rigidity. [4] b) True and Pseudo hermaphrodite. [3] c) Respiratory adjustments in infant to extrauterine life upon birth. [3]
  7. a) Describe the physiological mechanism of phasic and tonic stretch reflexes. [4] b) Describe the clinical significance of phasic and tonic stretch reflexes. [3] c) Add a note on alpha-gamma linkage. [3]
  8. a) Physio-clinical significance of Synaptic plasticity. [3] b) Physio-clinical significance of Mirror neurons. [3] c) Physio-clinical significance of Evoked Potentials. [4]
  9. Discuss the events occurring during excitation contraction coupling in smooth muscle. [10]
  10. a) Audiometry. [3] b) Transduction of gustatory stimuli. [3] c) Visual cortex. [4]

Paper 4

  1. a) Describe the sequential ECG changes seen in ST elevation -myocardial infarction, with suitable illustrations. [8] b) List the common complications associated. [2]
  2. a) Discuss the molecular mechanisms involved in encoding of memory. [8] b) Add a note on senile plaques. [2]
  3. Describe the Physiological principles underlying a) Bereitschafts potential. [5] b) Cardio pulmonary exercise testing. [5]
  4. a) Hypoglycemia. [3] b) Intention tremors. [3] c) Cochlear microphonics. [4]
  5. a) Define the term psycho neuroimmunology. [1] b) Discuss the pathophysiology of stress and its impact on the various organ systems. [9]
  6. a) Role of insulin resistance in diabetes mellitus. [3] b) Fever. [3] c) Neural centers involved in sleep. [4]
  7. a) Define infertility and discuss its pathophysiological basis. [8] b) Add a note on assisted reproductive techniques. [2]
  8. Explain the Physiological basis of a) Blood pressure variability. [3] b) Lateral inhibition and visual contrast mechanism in retina. [3] c) Physiological basis of Withdrawal reflex. [4]
  9. Discuss the recent advances in a) Interactive, online teaching tools. [5] b) Mechanism of circadian rhythm. [5]
  10. Explain the clinical relevance of a) Electroretinogram. [5] b) Ankle brachial index. [5]

High-Yield DNB Physiology Topics

A selection of 30 of the 44 important topics curated in the app from repeated DNB Physiology questions.

General and cell physiology — foundation

  • Homeostasis and feedback control (negative/positive feedback)
  • Cell membrane transport: diffusion, osmosis, active transport, resting membrane potential (Nernst/Goldman)
  • Action potential: ionic basis, refractory periods, propagation; graded potentials

Nerve and muscle

  • Neuromuscular junction: transmission, myasthenia gravis, Lambert-Eaton, NMJ blockers
  • Skeletal muscle: excitation-contraction coupling, motor unit, fiber types, muscle spindle
  • Smooth muscle: latch phenomenon, length-tension relationship

Blood and immunity

  • Hemostasis: platelet plug, coagulation cascade, fibrinolysis, PT/aPTT significance
  • Blood groups: ABO/Rh, erythroblastosis fetalis (pathophysiology, prevention)
  • Erythropoiesis regulation; anaemia and polycythaemia physiology

Cardiovascular system — high yield

  • Cardiac cycle: pressure-volume loops, heart sounds, cardiac output regulation
  • ECG: waves and intervals, arrhythmia basics, electrolyte effects (K+, Ca2+)
  • Frank-Starling mechanism; compensated vs decompensated heart failure

Respiratory system

  • Lung volumes and capacities; compliance and surfactant
  • Oxygen-haemoglobin dissociation curve: P50, Bohr effect, factors shifting curve
  • CO2 transport: Haldane effect; V/Q ratio, shunt, dead space

Renal and acid-base

  • Glomerular filtration: GFR regulation, clearance, RAAS
  • Tubular function: reabsorption/secretion, concentrating mechanism, ADH
  • Acid-base balance: Henderson-Hasselbalch, anion gap, renal compensation

GI and metabolism

  • GI motility: swallowing, gastric emptying, peristalsis; ENS
  • Digestion and absorption: carbohydrates, proteins, fats; bile and pancreatic enzymes
  • Liver functions: bilirubin metabolism, detoxification, synthetic functions

Endocrine system

  • Hypothalamic-pituitary axis: GH, ACTH, TSH, gonadotropins
  • Thyroid: synthesis, T3/T4 regulation, calcitonin; calcium-PTH-vitamin D axis
  • Adrenal cortex and medulla: cortisol, aldosterone, catecholamines

CNS and special senses

  • CSF production and circulation; blood-brain barrier
  • Vision: optics, phototransduction, colour vision, visual pathway lesions
  • Hearing: cochlear mechanics, auditory pathway, Weber/Rinne tests physiology

Environmental and integrative

  • Temperature regulation: heat loss mechanisms, fever, heat stroke physiology
  • Exercise physiology: VO2 max, anaerobic threshold, cardiovascular adaptation
  • Ageing physiology; pregnancy physiological changes (cardiovascular, respiratory, renal)

Older DNB Physiology Question Papers

The remaining 15 papers are available in the Prep DNB app, organized paper-wise with repeat-question tracking.

Get all 17 papers in the app

Previous Year Questions for Other DNB Subjects