# Explain how the structure of a red blood cell is adapted for its function of carrying oxygen.

> Eduqas GCSE Biology — 1.4.1 Blood and circulation · Explain · 4 marks

## Mark scheme (4 marks)

1. Red blood cells have a biconcave disc shape
2. This increases the surface area for absorption / diffusion of oxygen
3. Red blood cells have no nucleus
4. This leaves more space / room for haemoglobin, which carries oxygen

## Key terms

- [red blood cell](https://www.gradenine.co.uk/glossary/red-blood-cell)

## Related

- [Revision notes for Eduqas GCSE Biology](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-b9c0d665) · Published by Druglandscape Ltd.