# Explain how blood clotting protects the body when a blood vessel is damaged.

> Eduqas A-Level Biology — 2.1 Classification and biodiversity · Explain · 5 marks

> When a blood vessel is broken due to injury, a series of events takes place to prevent blood loss and stop pathogens from entering the body.

## Mark scheme (5 marks)

1. Platelets are involved in/responsible for blood clotting
2. Platelets stick to the broken vessel wall / clump together at the site of injury
3. This blocks the cut / forms a scab
4. Blood clotting prevents pathogens from entering the blood vessel / prevents infection
5. This allows the blood vessel to heal

## Key terms

- [blood clotting](https://www.gradenine.co.uk/glossary/blood-clotting)
- [blood vessel](https://www.gradenine.co.uk/glossary/blood-vessel)

## Related

- [Revision notes for Eduqas A-Level Biology](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)

---
Source: [GradeNine](https://www.gradenine.co.uk/q/explain-how-blood-clotting-protects-the-c5d20b0a) · Published by Druglandscape Ltd.