# Adrenaline is a hormone released during the 'fight-or-flight' response. Explain how adrenaline reaches its target organs and describe the effects it produces in the body to prepare an organism for danger.

> Eduqas A-Level Biology — 4.4 Application of reproduction and genetics · Explain · 5 marks

## Mark scheme (5 marks)

1. Adrenaline is produced/secreted by the adrenal gland
2. Adrenaline travels in the bloodstream to target organs
3. Adrenaline increases heart rate / pulse rate
4. Adrenaline increases breathing rate / blood flow to muscles
5. Adrenaline causes glycogen to be converted into glucose, increasing blood sugar levels / providing energy for respiration

## Key terms

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

## Related

- [Revision notes for Eduqas A-Level 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/adrenaline-is-a-hormone-released-during-d56de4df) · Published by Druglandscape Ltd.