# Explain how the body responds when blood glucose concentration falls below the optimum level. In your answer, name the hormone involved and describe the mechanism by which blood glucose concentration is returned to normal.

> WJEC A-Level Biology (Wales) — 4.2 Inheritance · Explain · 5 marks

## Mark scheme (5 marks)

1. The pancreas detects the fall in blood glucose concentration / low blood glucose is detected
2. Glucagon is released / secreted by the pancreas
3. Glucagon travels in the blood(stream) to the liver / glucagon is a chemical messenger carried in the blood
4. Glycogen is converted into glucose in the liver / glucagon stimulates the conversion of glycogen to glucose
5. Blood glucose concentration rises back to / returns to the optimum / normal level (negative feedback)

## Key terms

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

## Related

- [Revision notes for WJEC A-Level Biology (Wales)](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-the-body-responds-when-ce99ef31) · Published by Druglandscape Ltd.