MCAT Biology Notes

Free MCAT Bio/Biochem notes organized by the AAMC content outline: biomolecules, amino acids and enzymes, genetics, metabolism, cells and viruses, and every major organ system. High-yield coverage for the Biological and Biochemical Foundations section.

Organized by the AAMC content outline: chapters are grouped under the three Bio/Biochem foundational concepts (FC1 to FC3), and each card shows its AAMC content category. Every page covers concept summaries, key definitions, common exam traps, and 5 worked MCQs.

FC1: Biomolecules (1A to 1D)

Amino acids, proteins and enzymes, nucleic acids and gene expression, genetics, and metabolism. The heaviest-weighted concept in Bio/Biochem.

Biomolecules: Proteins, Enzymes, Carbs and Lipids

AAMC 1A, 1B, 5D · amino acids, protein structure, enzymes, carbs, lipids, DNA, RNA

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DNA Replication and Gene Expression

AAMC 1B · replication, repair, transcription, translation, operons

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Biotechnology and Lab Techniques

AAMC 1B · recombinant DNA, PCR, electrophoresis, CRISPR

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Mendelian Genetics and Inheritance

AAMC 1C · Mendel, linkage, X-linked, Hardy-Weinberg

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Cellular Respiration and Glucose Metabolism

AAMC 1D · glycolysis, citric acid cycle, ETC, ATP yield

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Nutrition and Energy Metabolism

AAMC 1D, 3B · macronutrients, vitamins, energy flow (plant content low-yield)

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FC2: Cells, Prokaryotes and Viruses (2A to 2C)

Membranes and organelles, bacteria and viruses, and cell division.

Cell Structure, Membranes and Organelles

AAMC 2A, 2B, 2C · membranes, transport, organelles, prokaryote vs eukaryote

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Viruses, Retroviruses and Prions

AAMC 2B · viral structure, life cycles, HIV, prions

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Cell Cycle, Mitosis and Differentiation

AAMC 2C · cell cycle, mitosis, checkpoints, cancer, apoptosis, stem cells, embryogenesis

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FC3: Organ Systems (3A, 3B)

Nervous and endocrine control, then each major organ system and how it maintains homeostasis.

Neurons and the Nervous System

AAMC 3A · neurons, action potential, spinal cord

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Synapses, Brain and Endocrine System

AAMC 3A · synapse, brain regions, hormones, feedback

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Cardiovascular System

AAMC 3B · heart, vessels, cardiac cycle, lymphatics

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Blood, Gas Transport and Clotting

AAMC 3B · blood composition, O2 and CO2 transport, blood groups, clotting

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Respiratory System

AAMC 3B · airways, breathing mechanics, gas exchange

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Digestive System

AAMC 3B · GI tract, enzymes, absorption

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Renal System and Homeostasis

AAMC 3B · nephron, ADH, thermoregulation, acid-base

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Immune System

AAMC 3B · innate vs adaptive, B and T cells, antibodies

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Musculoskeletal System

AAMC 3B · skeleton, joints, muscle contraction

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Reproductive System and Development

AAMC 3B, 1C, 2C · meiosis, gametogenesis, menstrual cycle, development

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How to use these notes

Read the chapter notes to build the concept layer.
Take a timed practice test on the chapter to validate recall under pressure.
Review wrong answers and re-read the relevant subtopic section in the notes.
Once comfortable, attempt full-length mocks on Practice Test.