---
title: "Cleavage Furrow — AP Bio Definition & Exam Guide"
description: "The cleavage furrow is the groove that pinches an animal cell in two during cytokinesis. Learn how it fits the cell cycle (Unit 4) and shows up on the AP Bio exam."
canonical: "https://fiveable.me/ap-bio/key-terms/cleavage-furrow"
type: "key-term"
subject: "AP Biology"
---

# Cleavage Furrow — AP Bio Definition & Exam Guide

## Definition

The cleavage furrow is a shallow groove in the cell membrane where cytoplasmic division will occur. It's the first sign of cytokinesis during cell division in an animal cell.

## Related Study Guides

- [4.6 Regulation of the Cell Cycle](/ap-bio/unit-4/cell-cycle/study-guide/4ztGMFvp0v4KAzL65pOP)

## Review

### Related Terms

- [Cytokinesis](/ap-bio/key-terms/cytokinesis): This is the process where one cell splits off from its sister cell. It usually follows mitosis and meiosis, which are types of nuclear division.
- [Cell Membrane](/ap-bio/key-terms/cell-membrane): This is a thin layer that surrounds every living cell, delimiting the cell from the environment around it. It plays a vital role in protecting the integrity of the interior of the cell by allowing certain substances into the cell while keeping other substances out.
- [Mitosis](/ap-bio/key-terms/mitosis): This is a part of cellular reproduction where the cell nucleus divides. The chromosomes separate into two identical sets in two separate nuclei.