# Genetic engineering can be used to produce human insulin in bacteria. Explain how bacteria are modified to produce human insulin.

> Pearson Edexcel A-Level Biology A (9BI0) — Topic 8 Use of Biological Resources · Explain · 5 marks

> Before genetic engineering was developed, insulin for treating diabetes was extracted from the pancreases of pigs and cattle. Scientists can now use genetically engineered bacteria to produce large quantities of human insulin.

## Mark scheme (5 marks)

1. The gene for human insulin production is identified / located in human DNA
2. The gene is cut out using enzymes (restriction enzymes)
3. A bacterial plasmid is cut open using (restriction) enzymes
4. The human insulin gene is inserted into the plasmid / the plasmid is sealed using ligase enzyme
5. The plasmid (now containing the human insulin gene) is inserted into a bacterium / the bacterium expresses the gene and produces insulin

## Key terms

- [genetic engineering](https://www.gradenine.co.uk/glossary/genetic-engineering)

## 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/genetic-engineering-can-be-used-to-6b40b96d) · Published by Druglandscape Ltd.