# A leaf contains palisade mesophyll tissue and spongy mesophyll tissue. Explain how these tissues contribute to the leaf working as an organ.

> AQA GCSE Biology (8461) — 4.2.1 Principles of organisation · Explain · 4 marks

## Mark scheme (4 marks)

1. A tissue is a group of cells with a similar structure and function
2. Palisade mesophyll is specialised to carry out photosynthesis
3. Spongy mesophyll is specialised for gas exchange
4. An organ is an aggregation of tissues performing a specific function / different tissues work together so the leaf can perform its overall function

## Key terms

- [tissue](https://www.gradenine.co.uk/glossary/tissue)
- [organ](https://www.gradenine.co.uk/glossary/organ)
- [palisade mesophyll](https://www.gradenine.co.uk/glossary/palisade-mesophyll)
- [spongy mesophyll](https://www.gradenine.co.uk/glossary/spongy-mesophyll)

## Related

- [Revision notes for AQA GCSE Biology (8461)](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-leaf-contains-palisade-mesophyll-tissue-70f0e7a9) · Published by Druglandscape Ltd.