# Explain why lipids are well suited as a long-term energy store in animals, compared to carbohydrates.

> AQA A-Level Biology (7402) — 3.1.3 Lipids · Explain · 5 marks

## Mark scheme (5 marks)

1. Lipids contain more energy per gram than carbohydrates
2. Lipids are insoluble in water
3. Being insoluble means lipids do not affect the water potential / osmotic balance of cells
4. Lipids are stored as fat / adipose tissue, which also provides insulation or protection
5. Carbohydrates (glycogen) are used for short-term / immediate energy needs, whereas lipids are used for long-term storage

## Key terms

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

## Related

- [Revision notes for AQA A-Level Biology (7402)](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-why-lipids-are-well-suited-efd8f4ac) · Published by Druglandscape Ltd.