# Explain why a plant with damaged roots that cannot absorb magnesium ions will show reduced rates of photosynthesis.

> Pearson Edexcel International GCSE Biology (4BI1) — 2.5 Nutrition: flowering plants · Explain · 4 marks

## Mark scheme (4 marks)

1. Magnesium ions are needed to make chlorophyll
2. Without magnesium, less / no chlorophyll is produced
3. Chlorophyll absorbs light energy for photosynthesis
4. Less light energy absorbed means photosynthesis occurs at a lower rate

## Key terms

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

## Related

- [Revision notes for Pearson Edexcel International GCSE Biology (4BI1)](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-a-plant-with-damaged-a77becf9) · Published by Druglandscape Ltd.