The AP® Biology textbook

8 units in framework order, then the skills the exam tests. Each topic is a notes page you can read on its own, free.

Units

Unit 1: Chemistry of Life

  1. Structure of Water and Hydrogen Bonding 1.1
  2. Elements of Life 1.2
  3. Introduction to Macromolecules 1.3
  4. Carbohydrates 1.4
  5. Lipids 1.5
  6. Nucleic Acids 1.6
  7. Proteins 1.7

Unit 2: Cell Structure and Function

  1. Cell Structure and Function 2.1
  2. Cell Size 2.2
  3. Plasma Membrane 2.3
  4. Membrane Permeability 2.4
  5. Membrane Transport 2.5
  6. Facilitated Diffusion 2.6
  7. Tonicity and Osmoregulation 2.7
  8. Mechanisms of Transport 2.8
  9. Cell Compartmentalization 2.9
  10. Origins of Cell Compartmentalization 2.10

Unit 3: Cellular Energetics

  1. Enzyme Structure 3.1
  2. Enzyme Catalysis 3.2
  3. Environmental Impacts on Enzyme Function 3.3
  4. Cellular Energy 3.4
  5. Photosynthesis 3.5
  6. Cellular Respiration 3.6

Unit 4: Cell Communication and Cell Cycle

  1. Cell Communication 4.1
  2. Introduction to Signal Transduction 4.2
  3. Signal Transduction Pathways 4.3
  4. Feedback 4.4
  5. Cell Cycle 4.5
  6. Regulation of Cell Cycle 4.6

Unit 5: Heredity

  1. Meiosis 5.1
  2. Meiosis and Genetic Diversity 5.2
  3. Mendelian Genetics 5.3
  4. Non-Mendelian Genetics 5.4
  5. Environmental Effects on Phenotype 5.5

Unit 6: Gene Expression and Regulation

  1. DNA and RNA Structure 6.1
  2. Replication 6.2
  3. Transcription and RNA Processing 6.3
  4. Translation 6.4
  5. Regulation of Gene Expression 6.5
  6. Gene Expression and Cell Specialization 6.6
  7. Mutations 6.7
  8. Biotechnology 6.8

Unit 7: Natural Selection

  1. Introduction to Natural Selection 7.1
  2. Natural Selection 7.2
  3. Artificial Selection 7.3
  4. Population Genetics 7.4
  5. Hardy-Weinberg Equilibrium 7.5
  6. Evidence of Evolution 7.6
  7. Common Ancestry 7.7
  8. Continuing Evolution 7.8
  9. Phylogeny 7.9
  10. Speciation 7.10
  11. Variations in Populations 7.11
  12. Origin of Life on Earth 7.12

Coming soon.

Unit 8: Ecology

  1. Responses to the Environment 8.1
  2. Energy Flow Through Ecosystems 8.2
  3. Population Ecology 8.3
  4. Effect of Density of Populations 8.4
  5. Community Ecology 8.5
  6. Biodiversity 8.6
  7. Disruptions to Ecosystems 8.7

Coming soon.

Skills

Statistics and math

  1. Mean, median, mode and range
  2. Graph construction
  3. Standard deviation and standard error
  4. Rates and percent change
  5. 95% confidence intervals and error bars
  6. Water potential calculations
  7. Chi-square test
  8. Hardy-Weinberg calculations
  9. Simpson's diversity index

Experimental design and argumentation

  1. Independent and dependent variables
  2. Controls and what they rule out
  3. Null and alternative hypotheses
  4. Claim, evidence and reasoning
  5. Prediction plus mechanism