# Explain how the phenotype of an organism is determined by both its genotype and the environment. Use examples in your answer.

> WJEC GCSE Biology (Wales) — 2.4.1 Variation · Explain · 4 marks

## Mark scheme (4 marks)

1. The phenotype is the physical characteristics / observable features of an organism
2. The genotype (the alleles present) influences the phenotype
3. Environmental factors can also affect the phenotype
4. A valid, relevant example of environmental influence on phenotype

## Key terms

- [phenotype](https://www.gradenine.co.uk/glossary/phenotype)
- [genotype](https://www.gradenine.co.uk/glossary/genotype)
- [environment](https://www.gradenine.co.uk/glossary/environment)

## 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-how-the-phenotype-of-an-b3ce4a05) · Published by Druglandscape Ltd.