1
Chemistry of Life
The properties of water and the biological macromolecules, carbohydrates, lipids, proteins, and nucleic acids, and how molecular structure gives rise to function.
AP Biology Units
All eight units of the AP Biology course framework, with approximate exam weighting and what each covers. The course runs from the chemistry of life through cell structure, cellular energetics, cell communication, heredity, gene expression, natural selection, and ecology. Units 3, 6, and 7 tend to carry the heaviest weighting, so budget your study time toward them. Approximate weightings are from the College Board Course and Exam Description; exact weightings vary year to year.
Total units
8
Heaviest unit
Unit 7
Also heavy
Units 3 & 6
Weighting source
CED
2
Cell Structure and Function
Organelles, membrane structure and transport (osmosis, diffusion, active transport), cell size and surface-area-to-volume, compartmentalization, and the origin of cells.
3
Cellular Energetics
Enzymes, cellular respiration, photosynthesis, energy flow through living systems, and molecular stability. One of the most heavily weighted units.
4
Cell Communication and Cell Cycle
Signal transduction, feedback mechanisms, the cell cycle and its regulation, and mitosis.
5
Heredity
Meiosis, Mendelian genetics, patterns of inheritance, chromosomal inheritance, and environmental effects on phenotype.
6
Gene Expression and Regulation
DNA and RNA structure and replication, transcription and translation, gene regulation, mutations, and biotechnology. One of the most heavily weighted units.
7
Natural Selection
Evidence for evolution, natural selection, population genetics and Hardy-Weinberg, speciation, phylogeny, and the origin of life. The heaviest unit on the exam.
8
Ecology
Communication and behavior, energy flow, population ecology, community and ecosystem dynamics, biodiversity, and disruptions to ecosystems.
Weightings above are the College Board's approximate multiple-choice ranges and shift slightly year to year. For more on the test itself, see the exam overview, free-response guide, practice questions, formula sheet, score calculator, and is it hard?