# Explain why micro-organisms such as bacteria and fungi are described as decomposers, and explain why this role is important in ecosystems.

> WJEC GCSE Biology (Wales) — 2.7 Micro-organisms and their applications · Explain · 4 marks

## Mark scheme (4 marks)

1. Decomposers break down dead organic material / dead organisms / waste material
2. They release nutrients / minerals into the soil
3. These nutrients can then be absorbed / taken up by plants
4. This recycles nutrients / allows nutrients to be reused in food chains / ecosystems

## Key terms

- [decomposers](https://www.gradenine.co.uk/glossary/decomposers)
- [ecosystems](https://www.gradenine.co.uk/glossary/ecosystems)
- [micro-organisms](https://www.gradenine.co.uk/glossary/micro-organisms)

## Related

- [Revision notes for WJEC GCSE Biology (Wales)](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-why-micro-organisms-such-as-bacteria-a221ee32) · Published by Druglandscape Ltd.