AP Biology

You think you're in charge, but your cells are running the whole show with a four-billion-year-old script.

17 days — make them count.

Monday, May 4, 2026

Start Unit 1 — it's free →Explore the course ↓

50%Multiple Choice60q · 90 min · calculator

50%Free Response6q · 90 min · calculator

of students scored 4 or higher in 2025

287,232 test-takers

2,695 colleges grant credit

5 · 19%

4 · 24%

3 · 27%

2 · 21%

1 · 9%

3.2 avg

543 (passing)21

Evolution is not one unit in AP Biology.

It is the organizing principle behind every unit. Once you see that, the course stops being a collection of facts and becomes a single argument.

Natural Selection carries the heaviest exam weight — master it, and you've anchored your score in the course's central argument.

Natural Selection carries the most weight on the AP exam, reflecting its central role in understanding biological processes, while Cellular Energetics and Gene Expression also have significant emphasis due to their complexity and importance.

How the course builds

Evolution · Energetics · Information Storage and Transmission · Systems Interactions

Chemistry of LifeEstablishes foundational molecular interactions essential for life.

8–11% of exam

Cell Structure and FunctionIllustrates how molecules organize into complex cellular architectures.

10–13% of exam

Cellular EnergeticsHighlights dynamic processes that sustain life.

12–16% of exam

Cell Communication and Cell CycleExplains regulation of growth and cellular processes.

10–15% of exam

HeredityIntroduces mechanisms of information transfer and variation.

8–11% of exam

★ Hardest unitGene Expression and RegulationDetails how genetic information is expressed and regulated.“Students often struggle with understanding the complex biochemical pathways and energy transformations.”

12–16% of exam

Natural SelectionExplores genetic variation and environmental pressures driving evolution.

13–20% of exam

EcologyExamines interactions and environmental shaping by evolved organisms.

10–15% of exam

Cellular Energetics is where most students hit a wall.

Students often struggle with understanding the complex biochemical pathways and energy transformations.

Lack of a strong foundation in basic chemistry concepts.

What You Need

Basic chemistryGraphing and data interpretationExperimental design and variables

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Unit 1 free · Course Pass $15 · All-Access $45 through May 31 —

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