# Explain how MRSA becomes resistant to antibiotics and why MRSA poses a particular danger to patients in hospitals.

> Cambridge International IGCSE Biology (0610) — 15.1 Drugs · Explain · 4 marks

> MRSA (methicillin-resistant Staphylococcus aureus) is a type of bacterium commonly found in hospitals that is resistant to almost all antibiotics.

## Mark scheme (4 marks)

1. A mutation occurs in a bacterial cell that makes it resistant to an antibiotic
2. When the antibiotic is used, non-resistant bacteria are killed but the resistant bacterium survives
3. The resistant bacterium reproduces, passing on resistance to offspring / producing more resistant bacteria
4. MRSA is resistant to almost all antibiotics, so infections are very difficult or impossible to treat

## Key terms

- [antibiotic](https://www.gradenine.co.uk/glossary/antibiotic)
- [MRSA](https://www.gradenine.co.uk/glossary/mrsa)

## Related

- [Revision notes for Cambridge International IGCSE Biology (0610)](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/explain-how-mrsa-becomes-resistant-to-5703c615) · Published by Druglandscape Ltd.