MDCAT Biology Syllabus 2026 — 81 MCQs (45%)
Biology is the single biggest subject on the MDCAT — 81 of 180 MCQs, 45% of the paper and nearly half of every mark on offer. It spans cell biology and biomolecules through genetics, evolution, and the full run of human physiology systems. Because it carries the most weight, a gap in any one chapter here costs more than the same gap anywhere else on the exam.
Acellular Life
- AIDS and HIV Infection
- Viruses
Bioenergetics
- ATP
- Cyclic and Non-Cyclic Photophosphorylation
- Fermentation
- Photosynthesis
- Pigments and Light Absorption
- Respiration
Biological Molecules
- Biological Importance of Water
- Biological Molecules (Definition and Classification)
- Biomolecules
- Carbohydrates
- Carotenoids
- Conjugated Molecules
- Lipids
- Nucleic Acids
- Proteins
- Ribonucleic Acid (RNA)
- Structure of DNA
- Water
Biotechnology
- Biotechnology
- Biotechnology and Health Care
- Cloning and Asexual Reproduction
- PCR and DNA Amplification
- Plant Tissue Culture
- Restriction Enzymes and Gene Isolation
- Vectors (Plasmids, Bacteriophages)
- cDNA Synthesis and Reverse Transcriptase
Cell Biology
- Cell Biology
- Cell Wall
- Chloroplasts
- Cytoskeleton
- ER
- Endosymbiotic Theory
- General
- Golgi
- Lysosomes
- Mitochondria
- Nucleus
- Ribosomes
Cell Cycle & Division
- Apoptosis
- Apoptosis (Programmed Cell Death)
- Cancer
- Cell Cycle
- Cell Cycle & Division
- General
- Interphase
- Meiosis
- Mitosis
- Regulation
Cell Membrane & Transport
- Aquaporins
- Cell Membrane & Transport
- Endocytosis
- Osmosis
- Structure
- Transport
Cell Structure and Function
- Cell Structure (Animal vs Plant)
- Chromosomes
- Cytoplasmic Organelles
- Prokaryotic and Eukaryotic Cell
Circulation
- Blood
- Blood Composition and Cells
- Blood Pressure
- Blood Vessels
- Blood Vessels (Arteries, Veins, Capillaries)
- Cardiac Cycle and Phases of Heartbeat
- Heart
- Human Heart
- Human Physiology - Circulation
- Lymphatic System
Classification & Diversity
- Animal Phyla
- Bacterial Reproduction
- Binomial Nomenclature
- Body Cavities (Coelom Classification)
- Classes of Fish (Agnatha, Chondrichthyes, Osteichthyes)
- Classification & Diversity
- Domains
- Kingdom Fungi
- Kingdom Prokaryotae (Bacteria)
- Kingdom Protista
- Kingdoms
- Phylum Arthropoda
- Phylum Chordata (Class Mammalia)
- Phylum Echinodermata
- Phylum Mollusca
- Phylum Nematoda
- Phylum Platyhelminthes
- Plants
- Taxonomy
Coordination and Control
- ANS
- Adrenal
- Animal Behaviour (Reflexes and Instincts)
- Brain
- CNS
- Disorders
- Endocrine System and Hormones
- Human Physiology - Nervous & Endocrine
- Hypothalamus
- Nerve Impulse and Reflexes
- Neurons
- Neurotransmitters
- Pancreas
- Parathyroid
- Pituitary
- Receptors
- Synapse
- Thyroid
Digestion
- Absorption
- Biological Importance of Water
- Eating Disorders
- Enzymes
- General
- Human Digestive System
- Human Physiology - Digestion
- Pancreas
- Small Intestine
- Stomach
- Vitamin Deficiency Diseases
Ecology
- Aquatic Zonation (Littoral, Profundal)
- Atmospheric Pollution (Ozone Depletion)
- Biological Control
- Biotic and Abiotic Components
- Ecology
- Energy Resources
- Eutrophication
- Food Chain and Food Web
- General
- Habitat and Niche
- Levels of Biological Organization
- Population Ecology
- Symbiotic Relationships
Enzymes
- Characteristics of Enzymes
- Classification
- Co-factors of Enzymes
- Enzyme Inhibitors
- Enzymes
- Factors Affecting Enzyme Action
- General
- Inhibition
- Kinetics
- Mechanism
- Mode of Enzyme Action
- Regulation
Evolution
- Concept of Evolution
- Darwinism
- Evidence
- Evolution
- Gene Linkage and Crossing Over
- Genetic Drift
- Hardy-Weinberg
- Lamarckism
- Selection
- Speciation
Homeostasis
- Disorders
- Excretion (Nitrogenous Compounds)
- Glomerular Filtration and Reabsorption
- Homeostasis
- Human Physiology - Excretion
- Kidney Stones and Failure
- Kidney Structure and Function
- Liver Functions
- Nephron
- Nitrogenous Wastes
- Osmoregulation
- Regulation
- Thermoregulation
Immunity
- Human Physiology - Immune System
- Non-Specific Defense Mechanism
- Specific Defense Mechanism
Inheritance
- Blood Groups
- Chromosomal Disorders
- Chromosome Number in Organisms
- Gene Interaction (Epistasis)
- Gene Linkage and Crossing Over
- Gene Location and Mapping
- Gene Mutation
- Genetics
- Hardy-Weinberg
- Human Disorders
- Incomplete Dominance and Codominance
- Mendel's Laws of Inheritance
- Mendelian
- Multiple Alleles
- Pedigree
- Polygenic inheritance
- Sex Determination
- Sex-linked
- X-linked Recessive Inheritance
- Y-linked Inheritance
Molecular Biology
- Chromosomal Mutations
- DNA Replication
- DNA Structure
- Gene Regulation
- Genetic Code
- Molecular Biology
- Mutations
- RNA
- Transcription
- Translation
Plant Biology
- Angiosperms vs Gymnosperms
- Classification of Plant Kingdom (Bryophyta, Pteridophyta)
- Economic Importance of Plants
- Nutrition
- Photoperiodism and Phytochrome
- Plant Biology
- Plant Hormones (Auxins, Gibberellins, etc.)
- Plant Movements (Tropic and Nastic)
- Plant Tissues (Parenchyma, Collenchyma, Sclerenchyma)
- Reproduction in Angiosperms (Double Fertilization)
- Stomata
- Transport
- Water Movement in Plants (Guttation, Transpiration)
Reproduction
- Development
- Female
- Germ Layers and Organogenesis
- Hormones
- Human Physiology - Reproduction
- Human Reproductive System
- Male
- Menstrual Cycle
- Sexually Transmitted Diseases
Respiration
- Anatomy
- Disorders
- Effect of Smoking
- Gas Exchange in Lungs
- Gas Transport
- Human Physiology - Respiration
- Human Respiratory System
- Lung Volumes
- Mechanism
- Regulation
- Respiratory Organs in Different Organisms
Support and Movement
- Arthritis
- Cartilages
- Disorders
- Human Skeleton (Cartilage, Muscle, Bone)
- Joints
- Muscle Contraction
- Muscles (Smooth, Cardiac, Skeletal)
- Skeletal Muscle Ultra-structure