AP Bio Unit 4 (Cell Communication; Feedback and Homeostasis; the Cell Cycle; Cancer and Apoptosis) Main Menu

Interactive tutorials are blue. Student Learning Guides (SLGs) are red. 

Note: The tutorials and student learning guides below have been updated to align with the College Board’s 2025 Course and Exam Description.

1. Topics 4.1 – 4.3: Cell Communication/Signal Transduction

Topics 4.1 – 4.3 (Cell Communication) Student Learning Guide

    1. Topic 4.1: Introduction to Cell Communication

    2. Topics 4.2 – 4.3, Part 1: Introduction to Signal Transduction

    3. Topics 4.2 – 4.3, Part 2: Reception

    4. Topics 4.2 – 4.3, Part 3: Signal Transduction

    5. Topics 4.2 – 4.3 Part 4: Signaling Hormones and Gene Regulation

    6. Topics 4-1 – 4.3: Cell Communication and Signal Transduction Cumulative Quiz

2. Topic 4.4: Feedback and Homeostasis

Topic 4.4 (Feedback and Homeostasis) Student Learning Guide

    1. Topic 4.4, Part 1: Homeostasis and Regulation (using thermoregulation as an illustrative example)

    2. Topic 4.4 Part 2: Feedback Loops

    3. Topic 4.4, Part 3: Blood Glucose Regulation (Illustrative Example)

    4. Topic 4.4, Part 4: Understanding Diabetes (Illustrative Example)

3. Topics 4.5 – 4.6: Mitosis, the Cell Cycle, and Cell Cycle Regulation

Topics 4.5 – 4.6 (Mitosis and the Cell Cycle; Cell Cycle Regulation; Cancer and Apoptosis) Student Learning Guide

    1. Topic 4.5: Mitosis and the Cell Cycle

    2. Topic 4.6, Part 1: Cell Cycle Regulation

    3. Topic 4.6, Part 2: Cancer and Apoptosis

4. Unit 4 Review Page: Objectives, Flashcards, and Quizzes