# Explain how the nervous system controls the secretion of adrenaline and describe two effects that adrenaline has on the body to prepare a person for sudden physical activity.

> Pearson Edexcel International GCSE Biology (4BI1) — 2.15 Coordination and response: humans · Explain · 4 marks

> During a sudden emergency, such as narrowly avoiding a collision whilst cycling, a person's heart rate increases rapidly and they feel a surge of energy. This response is triggered by a hormone released into the bloodstream.

## Mark scheme (4 marks)

1. The nervous system (via nerve impulses) stimulates the adrenal glands to release adrenaline
2. Adrenaline travels in the bloodstream to target organs
3. Adrenaline increases heart rate (accept: increases the rate and force of heartbeat)
4. Adrenaline causes one further correct effect: e.g. dilates the pupils / increases blood glucose concentration / diverts blood to muscles / causes faster / deeper breathing / inhibits digestive activity

## Key terms

- [adrenaline](https://www.gradenine.co.uk/glossary/adrenaline)
- [nervous system](https://www.gradenine.co.uk/glossary/nervous-system)

## Related

- [Revision notes for Pearson Edexcel International GCSE Biology (4BI1)](https://www.gradenine.co.uk/learn)
- [How to answer "Explain" questions](https://www.gradenine.co.uk/tools/command-word-cheatsheet)
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Source: [GradeNine](https://www.gradenine.co.uk/q/explain-how-the-nervous-system-controls-b063789a) · Published by Druglandscape Ltd.