# Explain how the structure of a triglyceride is related to its function as an energy storage molecule.

> IB DP Biology Higher Level (2023 syllabus) — B1.1 Carbohydrates and lipids · Explain · 4 marks

## Mark scheme (4 marks)

1. Triglycerides contain three fatty acid chains (and a glycerol backbone), providing a large number of C–H bonds
2. The high proportion of C–H bonds means triglycerides have a higher energy yield per gram than carbohydrates (approximately twice)
3. Triglycerides are non-polar / hydrophobic, so they do not associate with water molecules and are stored anhydrously
4. The long, largely saturated hydrocarbon tails pack closely together in adipose tissue, allowing dense storage of energy in a small volume

## Key terms

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

## Related

- [Revision notes for IB DP Biology Higher Level (2023 syllabus)](https://www.gradenine.co.uk/learn)
- [How to answer "Explain" questions](https://www.gradenine.co.uk/tools/command-word-cheatsheet)
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Source: [GradeNine](https://www.gradenine.co.uk/q/explain-how-the-structure-of-a-75fc6541) · Published by Druglandscape Ltd.