# Explain how adrenaline prepares the body for the 'fight or flight' response during a stressful situation such as running from danger.

> Edexcel A-Level Biology A: Salters-Nuffield (9BN0) — 7 Run for your Life · Explain · 5 marks

> During a stressful situation, the adrenal glands release a hormone into the bloodstream. This hormone brings about several changes in the body within seconds.

## Mark scheme (5 marks)

1. Adrenaline is produced/released by the adrenal glands
2. Adrenaline increases heart rate
3. Adrenaline increases blood flow to the muscles / so muscles receive more oxygen and glucose
4. Adrenaline increases blood glucose levels / causes glycogen to be broken down to glucose
5. Adrenaline increases blood pressure / so oxygen and glucose are delivered more rapidly to muscles for respiration / enabling a faster response to the stressor

## Key terms

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

## Related

- [Revision notes for Edexcel A-Level Biology A: Salters-Nuffield (9BN0)](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-adrenaline-prepares-the-body-22dfd9c6) · Published by Druglandscape Ltd.