AP Biology ยท all 8 units

Free AP Biology lessons, worked step by step

Start with the 8 free topics, taken from all 8 units of the course and with no account needed: read the idea, follow the worked examples, then practise. Every practice question brings new numbers each time, so you learn the method, not the answer.

Start the first free lesson See AP Biology Prep The formula sheet

Chemistry of Life

7 topics, 1 free

  1. Structure of Water and Hydrogen Bonding Free
  2. Elements of Life AP Biology Prep
  3. Introduction to Macromolecules AP Biology Prep
  4. Carbohydrates AP Biology Prep
  5. Lipids AP Biology Prep
  6. Nucleic Acids AP Biology Prep
  7. Proteins AP Biology Prep

Cell Structure and Function

10 topics, 1 free

  1. Cell Structure and Function AP Biology Prep
  2. Cell Size AP Biology Prep
  3. Plasma Membrane Free
  4. Membrane Permeability AP Biology Prep
  5. Membrane Transport AP Biology Prep
  6. Facilitated Diffusion AP Biology Prep
  7. Tonicity and Osmoregulation AP Biology Prep
  8. Mechanisms of Transport AP Biology Prep
  9. Cell Compartmentalization AP Biology Prep
  10. Origins of Cell Compartmentalization AP Biology Prep

Cellular Energetics

5 topics, 1 free

  1. Enzymes Free
  2. Environmental Impacts on Enzyme Function AP Biology Prep
  3. Cellular Energy AP Biology Prep
  4. Photosynthesis AP Biology Prep
  5. Cellular Respiration AP Biology Prep

Cell Communication and Cell Cycle

6 topics, 1 free

  1. Cell Communication AP Biology Prep
  2. Introduction to Signal Transduction AP Biology Prep
  3. Signal Transduction Pathways AP Biology Prep
  4. Feedback AP Biology Prep
  5. Cell Cycle Free
  6. Regulation of Cell Cycle AP Biology Prep

Heredity

5 topics, 1 free

  1. Meiosis Free
  2. Meiosis and Genetic Diversity AP Biology Prep
  3. Mendelian Genetics AP Biology Prep
  4. Non-Mendelian Genetics AP Biology Prep
  5. Environmental Effects on Phenotype AP Biology Prep

Gene Expression and Regulation

8 topics, 1 free

  1. DNA and RNA Structure AP Biology Prep
  2. DNA Replication AP Biology Prep
  3. Transcription and RNA Processing AP Biology Prep
  4. Translation Free
  5. Regulation of Gene Expression AP Biology Prep
  6. Gene Expression and Cell Specialization AP Biology Prep
  7. Mutations AP Biology Prep
  8. Biotechnology AP Biology Prep

Natural Selection

12 topics, 1 free

  1. Introduction to Natural Selection AP Biology Prep
  2. Natural Selection AP Biology Prep
  3. Artificial Selection AP Biology Prep
  4. Population Genetics Free
  5. Hardy-Weinberg Equilibrium AP Biology Prep
  6. Evidence of Evolution AP Biology Prep
  7. Common Ancestry AP Biology Prep
  8. Continuing Evolution AP Biology Prep
  9. Phylogeny AP Biology Prep
  10. Speciation AP Biology Prep
  11. Variations in Populations AP Biology Prep
  12. Origins of Life on Earth AP Biology Prep

Ecology

7 topics, 1 free

  1. Responses to the Environment AP Biology Prep
  2. Energy Flow Through Ecosystems AP Biology Prep
  3. Population Ecology Free
  4. Effect of Density on Populations AP Biology Prep
  5. Community Ecology AP Biology Prep
  6. Biodiversity AP Biology Prep
  7. Disruptions in Ecosystems AP Biology Prep