Biology
Biology covers a full year of introductory college biology, from molecules and cells through organisms to populations and ecology. It is one of the larger science exams and is widely accepted for laboratory-free science credit.
Start practice testAbout this exam
The exam divides into three roughly equal parts: molecular and cellular biology, organismal biology, and population biology including genetics, evolution and ecology.
Questions test understanding of process. You should be able to follow energy through a cell, trace inheritance through a cross, and predict what happens to a population under selection pressure.
It is a substantial exam, but the material is cumulative and rewards steady work rather than last-minute cramming.
Topic breakdown
Topic weights published by College Board.
How to study for this exam
- Start with cellular respiration and photosynthesis, which anchor much of the molecular section.
- Practise genetics problems until Punnett squares and probability feel routine.
- Learn the major organ systems at the level of function, not anatomical detail.
- Work through ecology and evolution last; they tie the earlier material together.
How the practice test works
- Choose all units or a single unit to focus on.
- Set the number of questions and a time limit, or practise untimed.
- Filter by difficulty to warm up or push yourself.
- Retake as many times as you like — every attempt is free.
- Your recent sessions stay on this device so you can review them.
Common questions
Is there a laboratory requirement?
The exam itself has no lab component. Some colleges award lab credit separately, so check before assuming it covers both.
How much chemistry do I need?
Basic chemistry helps for the molecular section, but the exam does not test chemistry directly.
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