# A plant is kept in darkness for 48 hours and then moved into bright light. Explain what happens to the rate of photosynthesis in the plant immediately after it is moved into the light, and describe how the products of photosynthesis are used once the rate has increased.

> Edexcel A-Level Biology A: Salters-Nuffield (9BN0) — 3.1 Photosynthesis · Explain · 5 marks

> Plants require specific conditions to carry out photosynthesis. The rate of photosynthesis can change rapidly when environmental conditions change.

## Mark scheme (5 marks)

1. Photosynthesis requires light as a source of energy, so moving the plant into bright light provides the energy needed to drive the reaction
2. The rate of photosynthesis increases (after exposure to light)
3. Glucose produced by photosynthesis is used in respiration to release energy for the plant
4. Glucose is converted into starch for storage in the plant
5. Glucose is used to make cellulose for cell walls, or combined with nitrates to make amino acids / proteins for growth and repair

## Key terms

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

## Related

- [Revision notes for Edexcel A-Level Biology A: Salters-Nuffield (9BN0)](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-plant-is-kept-in-darkness-2825a1ac) · Published by Druglandscape Ltd.