# Explain how collagen's structure is related to its function as a structural protein in connective tissue.

> IB DP Biology Standard Level (2023 syllabus) — B1.2 Proteins · Explain · 4 marks

## Mark scheme (4 marks)

1. Collagen consists of three polypeptide chains wound together into a triple helix
2. Hydrogen bonds (and/or cross-links) between the chains hold the triple helix together, giving tensile strength
3. Collagen triple helices aggregate into fibrils and fibres, creating an insoluble, rope-like structure
4. The resulting fibrous structure provides mechanical support / resists tension in connective tissues such as tendons, skin, or bone matrix

## Key terms

- [connective tissue](https://www.gradenine.co.uk/glossary/connective-tissue)
- [structural protein](https://www.gradenine.co.uk/glossary/structural-protein)

## 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-collagen-s-structure-is-related-5ecccb5d) · Published by Druglandscape Ltd.