# Describe how the immune system responds when a pathogen enters the body for the first time.

> WJEC GCSE Biology (Wales) — 2.8 Disease, defence and treatment · Describe · 4 marks

## Mark scheme (4 marks)

1. White blood cells / lymphocytes detect the antigen on the surface of the pathogen
2. Antibodies are produced that are specific / complementary to the antigen
3. Antibodies bind to / destroy / neutralise the pathogen
4. Memory cells are produced so the response is faster if the same pathogen is encountered again

## Key terms

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

## Related

- [Revision notes for WJEC GCSE Biology (Wales)](https://www.gradenine.co.uk/learn)
- [How to answer "Describe" questions](https://www.gradenine.co.uk/tools/command-word-cheatsheet)
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Source: [GradeNine](https://www.gradenine.co.uk/q/describe-how-the-immune-system-responds-5996d990) · Published by Druglandscape Ltd.