# Explain how the body responds to a sustained rise in core body temperature, such as during prolonged exercise, to restore homeothermy.

> IB DP Biology Higher Level (2023 syllabus) — D3.3 Homeostasis · Explain · 4 marks

## Mark scheme (4 marks)

1. Thermoreceptors in the hypothalamus detect a rise in blood/core temperature above the set point
2. Vasodilation of superficial/skin arterioles increases blood flow to the skin surface, increasing heat loss by radiation and convection
3. Sweat glands are stimulated to secrete sweat; evaporation of sweat from the skin surface removes latent heat
4. These responses constitute negative feedback: as core temperature returns to the set point, the effector responses are reduced/switched off

## Key terms

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

## Related

- [Revision notes for IB DP Biology Higher Level (2023 syllabus)](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-the-body-responds-to-838102ca) · Published by Druglandscape Ltd.