# A scientist is investigating DNA replication. Explain why it is important that DNA replication produces an exact copy of the original DNA, and describe the role of the nucleus in this process.

> Eduqas A-Level Biology — 1.5 Nucleic acids and DNA replication · Explain · 5 marks

> Before a eukaryotic cell can divide by mitosis, the DNA inside the cell must be replicated so that each daughter cell receives a complete set of genetic information.

## Mark scheme (5 marks)

1. DNA replication occurs in the nucleus
2. DNA contains all the genetic information / codes for proteins
3. Each daughter cell must receive an identical copy of the DNA so that they have the same genetic information as the parent cell
4. If the copy is not exact, the cell may not function correctly / mutations could occur
5. DNA is a polymer made of two strands twisted into a double helix, and replication ensures both new cells receive this complete double helix structure

## Key terms

- [DNA replication](https://www.gradenine.co.uk/glossary/dna-replication)
- [nucleus](https://www.gradenine.co.uk/glossary/nucleus)

## Related

- [Revision notes for Eduqas A-Level Biology](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-scientist-is-investigating-dna-replication-133e5690) · Published by Druglandscape Ltd.