---
title: "AP Biology Key Terms"
description: "939 AP Biology key terms and definitions organized by AP® Course and Exam Description unit."
canonical: "https://fiveable.me/ap-bio/key-terms"
type: "key-terms-hub"
subject: "AP Biology"
---

# AP Biology Key Terms

## Overview

939 AP Biology key terms and definitions organized by AP® Course and Exam Description unit.

## Units

- [Unit 1: Unit 1 – Chemistry of Life](/ap-bio/key-terms/unit/1): 82 terms across 7 topics
- [Unit 2: Unit 2 – Cell Structure and Function](/ap-bio/key-terms/unit/2): 127 terms across 10 topics
- [Unit 3: Unit 3 – Cellular Energetics](/ap-bio/key-terms/unit/3): 113 terms across 5 topics
- [Unit 4: Unit 4 – Cell Communication and Cell Cycle](/ap-bio/key-terms/unit/4): 93 terms across 6 topics
- [Unit 5: Unit 5 – Heredity](/ap-bio/key-terms/unit/5): 80 terms across 5 topics
- [Unit 6: Unit 6 – Gene Expression and Regulation](/ap-bio/key-terms/unit/6): 146 terms across 8 topics
- [Unit 7: Unit 7 – Natural Selection](/ap-bio/key-terms/unit/7): 134 terms across 12 topics
- [Unit 8: Unit 8 – Ecology](/ap-bio/key-terms/unit/8): 164 terms across 7 topics

## Related Resources

- [AP Biology subject hub](/ap-bio)
- [All AP® key terms](/key-terms)

## About This Document

Canonical Fiveable pages are available as Markdown at the same path plus `.md`.

- [llms.txt](https://fiveable.me/llms.txt): index of Fiveable's sections and URL patterns
- [llms-full.txt](https://fiveable.me/llms-full.txt): complete subject and unit listing
- [MCP server](https://fiveable.me/mcp): call Fiveable as tools instead of fetching pages (`https://fiveable.me/api/mcp`)
- [MCP server for AP teachers](https://fiveable.me/mcp/teachers): a teacher's classes, assignments and AP-rubric grading (`https://fiveable.me/api/mcp/teacher`)