# The Cell Cycle, Stage by Stage

> A dividing animal cell moves through a fixed order: interphase to prepare, then four stages of mitosis that share out the chromosomes, and finally cytokinesis that splits the cell in two. Step through the markers in order.

Web page: https://cellnaut.com/topics/cell-cycle-stages

![Teaching illustration: The Cell Cycle, Stage by Stage](https://cellnaut.com/topic-illustrations/cell-cycle-stages-teaching.jpg)

## Labelled parts

1. **1. Interphase**: The nucleus is intact and the DNA, loosely spread out, is copied before division.
2. **2. Prophase**: Chromosomes condense into X-shaped rods, the nuclear envelope breaks down and the spindle begins to form.
3. **3. Metaphase**: Chromosomes line up across the middle of the cell, each attached to spindle fibres from both poles.
4. **4. Anaphase**: The two copies of each chromosome are pulled apart toward opposite ends of the cell.
5. **5. Telophase**: New nuclear envelopes form around each set of chromosomes, which begin to spread out again.
6. **6. Cytokinesis**: The membrane pinches in at the middle, splitting the cell into two daughter cells.

## Key points

- Interphase is the longest part of the cycle; the DNA is copied before any visible division starts.
- Mitosis runs prophase, metaphase, anaphase, telophase, and each copy of a chromosome ends up in a different daughter nucleus.
- Cytokinesis divides the cytoplasm, so two separate cells result.

## Check yourself

**1. During which stage do the chromosomes line up in the middle of the cell?**

- A. Prophase
- B. Metaphase
- C. Anaphase
- D. Telophase

**Answer:** B. Metaphase - Metaphase means the chromosomes sit on the cell's equator, ready to be pulled apart.

**2. When is the DNA copied?**

- A. During interphase
- B. During anaphase
- C. During cytokinesis
- D. It is never copied

**Answer:** A. During interphase - The copying happens in interphase, so every chromosome is already doubled when mitosis begins.

## Related lessons

- [The Cell Cycle and Mitosis](https://cellnaut.com/learn/cell-division)

## See it in 3D

- [Stem Cell](https://cellnaut.com/studio/stem)
- [Animal Cell](https://cellnaut.com/studio/animal)

Explanations rewritten in our own words from Biology 2e, Chapter 10: Cell Reproduction (OpenStax), licensed CC BY-NC-SA 4.0. https://openstax.org/books/biology-2e/pages/10-introduction