# A biotechnology company has produced a genetically modified (GM) bacterium that contains a human gene. The bacterium produces a useful protein that can be used as a medicine. Explain how the bacterium is able to produce this human protein, and evaluate one advantage and one disadvantage of using GM bacteria to produce medicines in this way.

> OCR A-Level Biology B — Advancing Biology (H422) — 5.4 Cloning and biotechnology · Explain · 5 marks

> Genetic modification involves inserting a gene from one organism into another. Bacteria can be modified to carry human genes and then grown in large fermenters to produce useful proteins such as insulin.

## Mark scheme (5 marks)

1. The human gene (section of DNA) codes for the specific protein / codes for a specific amino acid sequence
2. The human gene has been inserted into the bacterium's DNA / genome
3. The bacterium uses the gene to produce / synthesise the human protein
4. Advantage: large quantities of the protein / medicine can be produced quickly / cheaply (accept: bacteria reproduce rapidly so large amounts can be made)
5. Disadvantage: there are ethical concerns about genetic modification / there is a risk the GM bacterium could escape into the environment and have unpredictable effects (accept: concerns about safety or ethics of altering an organism's genome)

## Key terms

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

## 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-biotechnology-company-has-produced-a-3ea3aa1c) · Published by Druglandscape Ltd.