# Describe how white blood cells protect the body against pathogens, including the roles of both phagocytes and lymphocytes.

> Cambridge International IGCSE Biology (0610) — 9.4 Blood · Describe · 4 marks

## Mark scheme (4 marks)

1. Phagocytes engulf pathogens by phagocytosis
2. Phagocytes release enzymes to digest / break down the engulfed pathogen
3. Lymphocytes produce antibodies that are specific to the antigen on the pathogen
4. Antibodies bind to antigens on pathogens, causing them to clump together / rendering them harmless

## Key terms

- [phagocyte](https://www.gradenine.co.uk/glossary/phagocyte)
- [lymphocyte](https://www.gradenine.co.uk/glossary/lymphocyte)

## Related

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Source: [GradeNine](https://www.gradenine.co.uk/q/describe-how-white-blood-cells-protect-bd5fa786) · Published by Druglandscape Ltd.