# A student suggests that homeostasis is only needed when a person is exercising. Evaluate this statement, using your knowledge of how the body monitors and responds to changes in its internal environment.

> Pearson Edexcel A-Level Biology A (9BI0) — 4.6 Homeostasis · Evaluate · 5 marks

> During a biology lesson, a student states: 'The body only needs to regulate its internal conditions during exercise, because that is when conditions change the most.'

## Mark scheme (5 marks)

1. Homeostasis is the maintenance of a constant internal environment
2. Homeostasis operates continuously / at rest as well as during exercise
3. Correct named example of a variable that is regulated at rest, e.g. blood glucose concentration / core body temperature / water content
4. Explanation of why the named variable must be kept constant — linked to cells / enzymes / metabolic reactions
5. Reasoned conclusion that the student's statement is incorrect / partially correct — e.g. acknowledging exercise increases the challenge to homeostasis but does not cause it to start

## Key terms

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

## Related

- [Revision notes for Pearson Edexcel A-Level Biology A (9BI0)](https://www.gradenine.co.uk/learn)
- [How to answer "Evaluate" 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-student-suggests-that-homeostasis-is-cb10bca2) · Published by Druglandscape Ltd.