# Explain why aerobic respiration is described as an exothermic reaction, and state where in the cell aerobic respiration takes place.

> OCR GCSE Biology A: Gateway Science (J247) — B1.3 Respiration · Explain · 4 marks

> During exercise, a student's muscles require a large and continuous supply of energy. The student's body relies mainly on aerobic respiration to meet this demand.

## Mark scheme (4 marks)

1. Aerobic respiration releases energy (from glucose)
2. An exothermic reaction is one that releases energy (as heat/ATP/to the surroundings)
3. Therefore aerobic respiration is exothermic because it releases energy (linking the two points together)
4. Aerobic respiration takes place in the mitochondria

## Key terms

- [aerobic respiration](https://www.gradenine.co.uk/glossary/aerobic-respiration)
- [exothermic reaction](https://www.gradenine.co.uk/glossary/exothermic-reaction)

## Related

- [Revision notes for OCR GCSE Biology A: Gateway Science (J247)](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-why-aerobic-respiration-is-described-6872cd3b) · Published by Druglandscape Ltd.