The AP Biology exam is one of the most challenging AP science tests, covering molecular biology, ecology, evolution, and more. A high score can earn you college credit and demonstrate strong STEM readiness.
This AP Bio study guide will walk you through the exam structure, core units, essential skills, and proven strategies — plus how RevisionDojo can help you prepare smarter, not harder.
AP Biology Exam Structure
The exam is 3 hours long, split into two sections:
Section I: Multiple Choice (MCQ)
- 60 questions, 90 minutes
- 50% of total score
- Questions often include charts, experimental data, and graphs
Section II: Free Response (FRQ)
- 6 questions total:
- 2 long free-response (one lab-based, one conceptual)
- 4 short-answer questions
- 90 minutes
- 50% of total score
AP Biology Units & Weighting
The College Board organizes AP Bio into 8 units:
- Chemistry of Life (8–11%)
- Cell Structure & Function (10–13%)
- Cellular Energetics (12–16%)
- Cell Communication & Cell Cycle (10–15%)
- Heredity (8–11%)
- Gene Expression & Regulation (12–16%)
