# Describe how oxygen produced during photosynthesis is removed from a flowering plant as a waste product of metabolism.

> Pearson Edexcel International GCSE Biology (4BI1) — 2.12 Excretion: flowering plants · Describe · 4 marks

> Flowering plants carry out photosynthesis, producing oxygen as a waste product. This oxygen must be removed from the plant body.

## Mark scheme (4 marks)

1. Oxygen diffuses out of the leaf (through the stomata)
2. Diffusion occurs down a concentration gradient, from higher concentration inside the leaf to lower concentration outside
3. Stomata are pores / openings found mainly on the lower surface of the leaf
4. Some oxygen is used in respiration within the plant (so only the excess / net surplus is removed as waste)

## Key terms

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

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Source: [GradeNine](https://www.gradenine.co.uk/q/describe-how-oxygen-produced-during-photosynthesis-a1ab6b43) · Published by Druglandscape Ltd.