# Describe how the human body produces monoclonal antibodies and explain one way in which they can be used in medicine.

> WJEC A-Level Biology (Wales) — 3.4 Population size and ecosystems · Describe and Explain · 5 marks

## Mark scheme (5 marks)

1. A specific antigen is injected into an animal (such as a mouse) to trigger an immune response
2. Lymphocytes are taken from the animal; these produce antibodies complementary to the antigen
3. Lymphocytes are fused with tumour cells to form hybridoma cells
4. Hybridoma cells divide continuously to produce large quantities of identical (monoclonal) antibodies
5. Named valid medical use correctly explained — e.g. in diagnostic tests (such as for HIV or Chlamydia) the monoclonal antibody binds to a specific molecule only present when the patient is positive for that disease, indicating a positive result; OR used in cancer treatment where monoclonal antibodies bind to antigens on cancer cells whilst carrying chemotherapy drugs to target them specifically

## Key terms

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

## Related

- [Revision notes for WJEC A-Level Biology (Wales)](https://www.gradenine.co.uk/learn)
- [How to answer "Describe and 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/describe-how-the-human-body-produces-11e31674) · Published by Druglandscape Ltd.