# Describe the roles of bile in the chemical digestion of fats in the duodenum.

> Cambridge International IGCSE Biology (0610) — 7.4 Chemical digestion · Describe · 4 marks

## Mark scheme (4 marks)

1. Bile neutralises the acidic contents entering the duodenum from the stomach
2. This provides a suitable / optimum pH for lipase to work in the small intestine
3. Bile emulsifies fats / oils into smaller droplets
4. Emulsification increases the surface area of fats for lipase to act upon, speeding up digestion

## Key terms

- [bile](https://www.gradenine.co.uk/glossary/bile)
- [duodenum](https://www.gradenine.co.uk/glossary/duodenum)

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Source: [GradeNine](https://www.gradenine.co.uk/q/describe-the-roles-of-bile-in-9721d7db) · Published by Druglandscape Ltd.