Important Topics in Physiology for NEET-PG 2025

Physiology is an important subject from Medical PG Entrance Exams perspective. It yields a high weightage in the exams. According to the recent official subject-wise marks distribution for NEET-PG, around 17 MCQ’s are expected from this subject.

To make your NEET PG preparations more effective, here’s a list of important Physiology topics that are likely to be asked in the exam.

Here's a list of the Physiology important topics that you must prepare thoroughly for the exam.

Important Topics in Physiology for NEET PG 

Homeostasis

• Control System
• Feedback Control System
• Negative Feedback Control System 
• The Feed forward Control System 

Body Fluids : Distribution and Management

• Body Water Percentage in the Body
• Transcellular Fluid
• Body Water Changes Along with Age
• Total Body Water
• Measurement of Body Water 
• The Shift of Body Water Between Different Compartments 
• Tonicity
• How is Plasma osmolality Calculated?
• Darrow-Yannet Diagram

Cell Physiology

• Cell Membrane 
• Composition of Cell/ Plasma Membrane
• Cell Cytoskeleton
• Drugs and Cytoskeleton
• Intercellular Junction
• Cell-to-cell interaction
• Cell to Basement Interaction 
• Structure of Gap Junction
• Connexins in disease
• Intercellular Junctions 

Transport Across Cell Membrane

• Transporter Molecules
• Kinetics of Carrier Protein
• Types of Transport
• Structure of Na-K-ATPase
• Secondary Active Transport 
• Passive Transport
• Osmosis
• Diffusion
• Non-Ionic Diffusion 
• Endocytosis
• Exocytosis

Neuron And Nerve

• Nerve
• Blood Neuron Barrier
• Blood-Brain Barrier (BBB)
• Structure of a Single Neuron
• Functional Areas of the Neuron
• Different Types of Neurons
• Axonal Transportation 

Resting Membrane Potential

• Arrangement of Resting Membrane Potential
• Origin of Resting Membrane Potential 
• Donnan's Effect 
• Donnan Equation
• Leak Channels
• Nernst Equation 
• Application of Nernst Equation
• Equilibrium Potential of Ions in Various Mammalian Cells 
• RMP of Various Cells

Action Potential in Neuron

• Resting Membrane Potential (RMP)
• Action Potential 
• Different Parts of Action Potential 
• Permeability of different ions during Action Potential 
• Sodium Channel
• Potassium Channel
• Refractory Period
• Different Stages of Voltage-Gated Sodium Channel

Nerve Fibre Classification

• Conduction of Action Potential 
• Classification of Nerve Fibres 
• Conduction Velocity of nerve fibres
• Diameter of the Nerve Fibres
• Compound Action Potential
• Stimulus Parameters
• Excitability of the Tissue
• Strength-Duration Curve
• Finding out the Rheobase, utilization time and the Chronaxie from the curve

Functional Anatomy of Skeletal Muscle 

• Muscle Physiology 
• Skeletal Muscle
• Sarcolemma
• Sarcotubular System
• Excitation - contraction coupling of skeletal muscle and cardiac muscle
• Revision of Previous Topics
• Myofibril Structure
• Structure of Sarcomere 
• Regulatory Protein 
• Molecular Mechanism 
• Anchoring Protein
• Electron microscopic structure of sarcomere
• Cross-Bridge formation
• Length-Tension Relationship 

Motor Unit

• Introduction
• Recruitment & Derecruitment
• Force Production by Skeletal Muscles
• Multiple Stimulations
• Multiple stimulations with different Frequency
• Increased Frequency of Stimulus
• Tetanizing Frequency (TF) 
• Applied aspect of Motor Unit
• Fasciculation
• Fibrillation
• Classification of the Skeletal Muscle Fibre

Smooth Muscle

• Features of Smooth Muscles
• Sources of Ca++ For Smooth Muscle Contraction
• Mechanism of Smooth Muscle Contraction

Conducting System of the Heart

• Muscles of the Heart
• Features of Myocardium
• Myosin
• Single Nucleus
• Intercalated Disc and Desmosome
• Gap Junction
• Functions of Gap Junction
• Syncytial tissue
• Presence of branching in the myocardium at regular intervals
• Comparison Between Myocardium and Skeletal Muscles
• Features of Modified Myocardium
• Heart Rate of a Transplanted Heart
• Complete Heart Block
• Conducting System of the Heart
• Comparison of the SA Node and the AV Node 
• AV Nodal Delay
• HIS Bundle Delay
• Conduction Velocity of Impulses in Different Parts of the Heart
• Reasons for High Conduction Velocity of Purkinje Fiber
• Depolarization and Repolarization 

Action Potential on Heart

• Electrical activity of the heart
• Resting Membrane Potential of Heart Muscles
• Fast Type of Action Potential
• Ionic Basis of Fast Type Action Potential 
• Ionic Basis of Relaxation of Myocardium Cells

ECG : Basic Concepts

• The Basics of ECG 
• Action Potential and ECG: Differences and Similarities
• Generation of the P wave
• Types of Leads
• Standard Bipolar Limb Leads
• Voltage Calculation
• Augmented Limb Leads
• Direction of Leads
• Chest (Precordial) Leads
• The Function of Leads
• Generation of The QRS Complex
• Schematic Diagram of the Ventricle with Leads
• Precordial Leads (Horizontal Plane)
• Precordial Leads (Horizontal Plane)
• Calculation of the Heart Rate from ECG
• Cardiac Axis Calculation
• His Bundle Electrogram

Cardiac Cycle

• Duration of The Cardiac Cycle
• Example Problem
• Phases of The Cardiac Cycle
• Diastole and Systole

Isovolumic Contraction 

• Rapid Ejection Phase and Slow Ejection Phase
• Total Amount of Blood Going out of the Ventricular Cavity
• Generation of the 1st and 2nd Heart Sounds
• Correlation of Heart Sounds with the ECG
• First Heart Sound
• Second Heart Sound
• Third and Fourth Heart Sounds
• Changes in Pressure During Cardiac Cycle
• Ventricular Pressure Curve
• Aortic Pressure Curve
• Carotid Pressure Curve 
• Pressure Changes in the Atrium 
• Valvular Stenosis
• Aortic Valve Stenosis
• Mitral Valve Stenosis

Cardiac Output

• Measurement of Cardiac Output 
• Fick's Principle
• Dye Dilution Method
• Thermodilution Method
• Regulation of Cardiac Output 
• Preload
• Contractility
• Afterload
• The Frank-Starling Law (FSL)
• Changes in the Curve Upon Different Treatments
• P-VLoop of the Cardiac Cycle 
• Aortic Regurgitation and Mitral Regurgitation
• Cardiomyopathies

Hematopoiesis and Blood Cells

• Hematopoiesis
• Site of Hematopoiesis: Niche
• Stem Cells
• Types of Stem Cells
• Blood Cells 
• Platelets

Hemostasis

• Primary Platelet Plug Formation
• Definitive Plug (Secondary Hemostatic Clog) 
• Coagulation Pathway Investigation

Functional Anatomy of Renal Physiology

• Nephrons
• Types of Nephrons
• Differences Between Cortical and Juxtamedullary Nephrons
• Structure of Nephron 
• Comparison Between the Epithelial Cells of PCT and Collecting Duct (CD)

GFR and Its Regulation

• Glomerular Filtration Barrier 
• Substances at the Barrier
• Net Force for Filtration
• Glomerular Filtration Rate (GFR) 
• Regulators of GFR 
• Autoregulation
• Afferent Arteriole (AA) & Efferent Arterioles (EA) Resistance
• Mediators Responsible for Regulation of GFR

JG Apparatus

• Components of JuxtaglomerularApparatus 
• Mechanism of Action of Juxtaglomerular Cells 
• Mechanism of Action of Macula Densa Cells

Clearance

• Concept of Clearance 
• Creatinine Amount in Urine 
• Source of any Substance in the Urine
• Clearance of Inulin
• Clearance of a Substance Secreted at Nephron 
• Clearance of a Substance that is Reabsorbed at the Nephron
• Transport Maximum of PAH

Tubular Transport

• Glomerulo-Tubular Balance
• Reabsorption of Different Substances
• Na+ Reabsorption
• Proximal Tubule (Mainly PCT) 
• Thick Ascending Limb (TAL)
• Bartter's Syndrome
• Distal Convoluted Tubule (DCT)
• Mutation of NCC
• Collecting Duct (CD) 
• Mutation of ENAC Channel
• Glucose Transport in different parts of the nephron 
• Transport Maximum of Glucose
• Renal Threshold
• Splay effect
• Water Reabsorption
• Potassium Reabsorption

Acid Secretion in Kidney

• Acid Secretion at the Level of PCT
• Acid Secretion at the Level of PST and TAL
• Acid secretion at the level of DCT/CT
• Buffers in the urine
• Renal TubularAcidosis 

Counter Current System

• Counter-Current System in Kidney: Mechanism 
• Countercurrent Multiplier
• Countercurrent Exchanger: Mechanism

Respiratory system 

• Functional Anatomy of the Respiratory System
• Mechanics of Respiration
• Ventilation - Perfusion of Lungs
• Compliance of Lungs
• Lung Volume and Capacities
• Principles of Gas Diffusion
• Oxygen Transport
• Carbon Dioxide Transport
• Regulation of Respiration
• Hypoxia
• High Altitude Physiology
• Deep Sea Diving

Gastrointestinal System

• Motility of GIT
• GI Hormones
• Secretion and Absorption

Nervous System

• Synapse : Pre Synaptic Events
• Synapse : Post Synaptic Events
• Synaptic Inhibition
• Somatosensory Receptors
• Nociceptors
• Proprioceptors and Reflexes
• Ascending Tracts of Spinal Cord
• Descending Tracts of Spinal Cord
• Basal Ganglia and Cerebellum
• Special Senses Visual and Auditory Receptors
• Special Senses Smell and Taste Receptors
• Hypothalamus and Limbic System
• EEG and Sleep
• Learning and Memory

Endocrine System

• Mechanisms of Hormone Actions
• Pituitary Hormones
• Thyroid Hormones
• Endocrine Pancreas
• Hormonal Regulation of Calcium Balance
• Adrenal Physiology
• Male Reproductive Physiology
• Female Reproductive Physiology

Dr. Soumen Manna has a complete one year preparation guide for students who are targeting NEET PG. Watch him discussing the preparation strategy in the video below:

Besides the important topics for physiology for NEET PG, we have also prepare a list of all the high-yield topics for different subjects. Please refer to the table below -