# A student places a green plant in a windowsill on a sunny day. After several hours, small bubbles are seen rising from the leaves when the plant is submerged in water. Explain what these bubbles are and why they are being produced.

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

## Mark scheme (4 marks)

1. The bubbles are oxygen
2. Oxygen is a product of photosynthesis
3. Light is required / the plant is photosynthesising because it is in sunlight
4. Carbon dioxide and water are converted into glucose (and oxygen) during photosynthesis

## 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/a-student-places-a-green-plant-50110987) · Published by Druglandscape Ltd.