# Explain how the body produces antibodies following a vaccination, and explain why a vaccinated person is protected if they later encounter the same pathogen.

> AQA A-Level Biology (7402) — 3.2.4 Cell Recognition and the Immune System · Explain · 5 marks

## Mark scheme (5 marks)

1. The vaccine contains antigens (from the pathogen / dead or weakened pathogen)
2. White blood cells / lymphocytes detect the antigens and produce antibodies complementary to / specific to those antigens
3. Memory cells are produced / remain in the body after the initial immune response
4. If the same pathogen enters the body again, memory cells recognise the antigens and respond rapidly
5. Antibodies are produced in large quantities / before the person becomes ill, so the pathogen is destroyed before symptoms develop

## Key terms

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

## Related

- [Revision notes for AQA A-Level Biology (7402)](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-the-body-produces-antibodies-85c68ae8) · Published by Druglandscape Ltd.