# A footballer suffers a serious knee injury that destroys cartilage cells. A doctor explains that adult stem cells from the patient's own body could be used to repair the damaged tissue. Explain why adult stem cells from the patient's own body are used in this treatment rather than embryonic stem cells, and describe the process by which the stem cells would produce new cartilage cells.

> Edexcel GCSE Biology (1BI0) — 2.2 Cell differentiation, growth and stem cells · Explain · 4 marks

## Mark scheme (4 marks)

1. Adult stem cells are less likely to be rejected because they come from the patient's own body (genetically identical to the patient)
2. Using embryonic stem cells raises ethical concerns / embryos are destroyed to obtain them
3. Cell differentiation — the undifferentiated stem cells differentiate / become specialised
4. The stem cells divide by mitosis (before or during differentiation) to produce new cells / increase the number of cells available

## Key terms

- [adult stem cells](https://www.gradenine.co.uk/glossary/adult-stem-cells)
- [embryonic stem cells](https://www.gradenine.co.uk/glossary/embryonic-stem-cells)

## Related

- [Revision notes for Edexcel GCSE Biology (1BI0)](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/a-footballer-suffers-a-serious-knee-c0b27022) · Published by Druglandscape Ltd.