# Explain how the endocrine system and the digestive system are integrated to regulate blood glucose concentration after a carbohydrate-rich meal.

> IB DP Biology Standard Level (2023 syllabus) — C3.1 Integration of body systems · Explain · 4 marks

## Mark scheme (4 marks)

1. Digestion of carbohydrates in the small intestine releases glucose, which is absorbed into the blood, causing blood glucose concentration to rise.
2. The rise in blood glucose is detected by beta cells in the islets of Langerhans in the pancreas, which is an endocrine gland.
3. Beta cells secrete insulin into the blood, which travels to target cells (liver, muscle, adipose tissue).
4. Insulin stimulates uptake of glucose by cells and promotes conversion of glucose to glycogen (glycogenesis) in the liver/muscle, lowering blood glucose back to the normal range.

## Key terms

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

## Related

- [Revision notes for IB DP Biology Standard Level (2023 syllabus)](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-endocrine-system-and-1b584bfc) · Published by Druglandscape Ltd.