All AP Courses

Unit 4

AP Biology Unit 4: Cell Communication and Cell Cycle

10–15% of the multiple-choice section · 6 topics

How cells signal one another, signal transduction, feedback, and the cell cycle and its regulation.

Topics

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

Unit check

10 questions drawn from every lesson in Unit 4. Each wrong answer links back to where the idea is taught.

Take the Unit 4 check