# Describe the role of red blood cells in transporting oxygen around the body.

> Pearson Edexcel International GCSE Biology (4BI1) — 2.11 Transport: humans · Describe · 4 marks

## Mark scheme (4 marks)

1. Red blood cells contain haemoglobin
2. Haemoglobin combines with / binds to oxygen (in the lungs) to form oxyhaemoglobin
3. Oxyhaemoglobin releases / dissociates to release oxygen at the tissues / body cells
4. Red blood cells are biconcave / have a large surface area (to volume ratio) to maximise oxygen uptake / diffusion of oxygen

## Key terms

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

## Related

- [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-red-blood-9b8c8279) · Published by Druglandscape Ltd.