# Describe how the structures found in a leaf are organised to allow the leaf to carry out photosynthesis efficiently. Refer to the levels of organisation in your answer.

> Edexcel GCSE Biology (1BI0) — 1.2 Levels of organisation · Describe · 4 marks

> A leaf is a complex structure made up of different types of cells that work together to carry out photosynthesis. Scientists use the concept of levels of organisation to describe how living things are built up from smaller components.

## Mark scheme (4 marks)

1. Cells are the basic unit of organisation; individual cells (e.g. palisade mesophyll cells) carry out photosynthesis
2. Similar cells are grouped together to form tissue (e.g. palisade mesophyll tissue / spongy mesophyll tissue)
3. Different tissues work together to form an organ — the leaf is the organ
4. Organs work together in an organ system / the leaf is part of the shoot system / plant organ system that transports materials needed for photosynthesis

## Key terms

- [organ](https://www.gradenine.co.uk/glossary/organ)
- [levels of organisation](https://www.gradenine.co.uk/glossary/levels-of-organisation)

## Related

- [Revision notes for Edexcel GCSE Biology (1BI0)](https://www.gradenine.co.uk/learn)
- [How to answer "Describe" 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-structures-found-in-9673f23d) · Published by Druglandscape Ltd.