# Explain how vaccination protects a person from becoming seriously ill when they are later infected by a pathogen.

> Eduqas GCSE Biology — 3.3 Treating, curing and preventing disease · Explain · 4 marks

## Mark scheme (4 marks)

1. The vaccine contains a weakened, dead or harmless form of the pathogen (or its antigens)
2. The immune system produces antibodies in response to the antigens in the vaccine
3. Memory cells are produced that remain in the body long-term
4. On re-exposure to the same pathogen, memory cells allow a faster/greater antibody response so the pathogen is destroyed before serious illness develops

## Key terms

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

## Related

- [Revision notes for Eduqas GCSE 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)

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Source: [GradeNine](https://www.gradenine.co.uk/q/explain-how-vaccination-protects-a-person-711619e2) · Published by Druglandscape Ltd.