# A student learns that a mutation in a gene can change the protein that a cell produces. Explain how a gene controls the production of a specific protein, and suggest how a mutation in the gene could affect the protein produced.

> OCR A-Level Biology B — Advancing Biology (H422) — 5.1 Genetic control of protein synthesis · Explain · 5 marks

> Proteins are made inside cells using genetic information stored in DNA. A change to this information can alter the protein that is made.

## Mark scheme (5 marks)

1. A gene is a section of DNA that codes for a specific amino acid sequence
2. mRNA carries the genetic information from the nucleus to the ribosomes (transcription)
3. At the ribosomes, the amino acids are joined together in the correct sequence to make a specific protein (translation)
4. A mutation is a random change in the DNA / base sequence of the gene
5. A mutation can change the amino acid sequence, so a different (non-functional / altered) protein may be produced — or the protein may be unchanged (neutral effect)

## Key terms

- [gene](https://www.gradenine.co.uk/glossary/gene)
- [mutation](https://www.gradenine.co.uk/glossary/mutation)

## Related

- [Revision notes for OCR A-Level Biology B — Advancing Biology (H422)](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-student-learns-that-a-mutation-83f98893) · Published by Druglandscape Ltd.