# Explain why plants need both light and chlorophyll to carry out photosynthesis.

> WJEC GCSE Biology (Wales) — 1.5.2 Photosynthesis · Explain · 4 marks

## Mark scheme (4 marks)

1. Light provides the energy needed for photosynthesis
2. This energy is used to convert carbon dioxide and water into glucose (and oxygen)
3. Chlorophyll absorbs the light energy
4. Without chlorophyll, light energy cannot be absorbed / photosynthesis cannot occur

## Key terms

- [photosynthesis](https://www.gradenine.co.uk/glossary/photosynthesis)
- [chlorophyll](https://www.gradenine.co.uk/glossary/chlorophyll)

## Related

- [Revision notes for WJEC GCSE Biology (Wales)](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-plants-need-both-light-a3352f7e) · Published by Druglandscape Ltd.