# Describe the role of bile in the digestion of lipids in the human digestive system.

> Pearson Edexcel International GCSE Biology (4BI1) — 2.6 Nutrition: humans · Describe · 4 marks

> Lipids are a group of large molecules made from fatty acid chains and glycerol. Before lipase can act efficiently on lipids, bile plays an important preparatory role in the duodenum.

## Mark scheme (4 marks)

1. Bile is produced in the liver (and stored in the gallbladder)
2. Bile emulsifies fats / lipids
3. Emulsification increases the surface area of lipid droplets available for lipase to act on
4. Bile neutralises stomach acid in the duodenum, providing a suitable pH for lipase to work

## Key terms

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

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- [Revision notes for Pearson Edexcel International GCSE Biology (4BI1)](https://www.gradenine.co.uk/learn)
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Source: [GradeNine](https://www.gradenine.co.uk/q/describe-the-role-of-bile-in-70394286) · Published by Druglandscape Ltd.