# A cell in the root tip of a pea plant completes the cell cycle and produces two daughter cells. Explain the roles of interphase and mitosis in ensuring that each daughter cell is diploid and genetically identical to the original parent cell.

> Pearson Edexcel A-Level Biology A (9BI0) — 2.2 Cell cycle and mitosis · Explain · 5 marks

## Mark scheme (5 marks)

1. During interphase, DNA replication occurs so that each chromosome is copied
2. This produces two chromatids per chromosome, so all the genetic information is present in duplicate
3. During metaphase, chromosomes align at the cell equator, and during anaphase, chromatids are pulled to opposite poles by spindle fibres
4. Each new nucleus therefore receives one copy of every chromatid / chromosome, giving the same genetic information as the parent cell
5. Cytokinesis then divides the cytoplasm to produce two diploid daughter cells, each with two copies of every chromosome

## Key terms

- [interphase](https://www.gradenine.co.uk/glossary/interphase)
- [mitosis](https://www.gradenine.co.uk/glossary/mitosis)
- [diploid](https://www.gradenine.co.uk/glossary/diploid)

## Related

- [Revision notes for Pearson Edexcel A-Level Biology A (9BI0)](https://www.gradenine.co.uk/learn)
- [How to answer "Explain" questions](https://www.gradenine.co.uk/tools/command-word-cheatsheet)
- [Practice this with AI marking (free)](https://www.gradenine.co.uk/start)

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Source: [GradeNine](https://www.gradenine.co.uk/q/a-cell-in-the-root-tip-acdc97d0) · Published by Druglandscape Ltd.