# Explain why a person who has received a transplanted organ may need to take immunosuppressant drugs for the rest of their life.

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

> Organ transplants save thousands of lives each year. However, recipients must take medication to prevent their immune system from attacking the transplanted organ.

## Mark scheme (5 marks)

1. The transplanted organ has different antigens (on its cell surface) to the recipient's own cells
2. The recipient's immune system recognises the organ's antigens as foreign / non-self
3. The immune system produces antibodies against / attacks the transplanted organ (rejection)
4. Immunosuppressant drugs reduce / suppress the immune response
5. The drugs must be taken continuously because the organ's foreign antigens are always present / the immune system would otherwise keep responding

## Key terms

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

## 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-why-a-person-who-has-25b5531c) · Published by Druglandscape Ltd.