# Describe the route taken by a red blood cell as it travels from the vena cava to the aorta, naming the chambers and valves it passes through in the correct order.

> Cambridge International IGCSE Biology (0610) — 9.1 Circulatory systems · Describe · 4 marks

## Mark scheme (4 marks)

1. Blood enters the right atrium from the vena cava and passes through the tricuspid valve into the right ventricle.
2. Blood leaves the right ventricle through the semilunar valve into the pulmonary artery and travels to the lungs.
3. Oxygenated blood returns from the lungs via the pulmonary vein into the left atrium and passes through the bicuspid valve into the left ventricle.
4. Blood leaves the left ventricle through the semilunar valve into the aorta; the left ventricle wall is thicker than the right as it must pump blood at higher pressure around the whole body.

## Key terms

- [vena cava](https://www.gradenine.co.uk/glossary/vena-cava)
- [aorta](https://www.gradenine.co.uk/glossary/aorta)

## Related

- [Revision notes for Cambridge International IGCSE Biology (0610)](https://www.gradenine.co.uk/learn)
- [How to answer "Describe" questions](https://www.gradenine.co.uk/tools/command-word-cheatsheet)
- [Practice this with AI marking (free)](https://www.gradenine.co.uk/start)

---
Source: [GradeNine](https://www.gradenine.co.uk/q/describe-the-route-taken-by-a-f15416f6) · Published by Druglandscape Ltd.