# Explain why it is important for the human body to maintain a constant internal environment.

> Eduqas GCSE Biology — 4.3 Homeostasis in humans · Explain · 4 marks

## Mark scheme (4 marks)

1. Enzymes work best at a specific/optimum temperature (or pH)
2. If conditions change, enzyme activity decreases / enzymes may denature
3. This would slow down or stop metabolic reactions / chemical reactions in cells
4. Maintaining constant conditions allows cells/organs to function correctly / ensures survival

## Key terms

- [internal environment](https://www.gradenine.co.uk/glossary/internal-environment)

## Related

- [Revision notes for Eduqas GCSE Biology](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-it-is-important-for-0baf9176) · Published by Druglandscape Ltd.