# Explain how insulin and glucagon work together to maintain a stable blood glucose concentration when blood glucose concentration first rises above the normal level and then falls below it.

> Cambridge International IGCSE Biology (0610) — 14.3 Hormones · Explain · 4 marks

## Mark scheme (4 marks)

1. When blood glucose concentration is too high, the pancreas secretes insulin.
2. Insulin causes liver (and muscle) cells to take up glucose and convert it to glycogen, lowering blood glucose concentration.
3. When blood glucose concentration falls too low, the pancreas secretes glucagon.
4. Glucagon causes the breakdown of glycogen to glucose in the liver, raising blood glucose concentration back to normal — this is an example of negative feedback.

## Key terms

- [insulin](https://www.gradenine.co.uk/glossary/insulin)
- [glucagon](https://www.gradenine.co.uk/glossary/glucagon)
- [blood glucose concentration](https://www.gradenine.co.uk/glossary/blood-glucose-concentration)

## Related

- [Revision notes for Cambridge International IGCSE Biology (0610)](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-insulin-and-glucagon-work-3f1f36fc) · Published by Druglandscape Ltd.