# Describe the roles of producers and primary consumers in a food chain, and explain how energy is transferred between them.

> WJEC GCSE Biology (Wales) — 1.6.1 Ecosystems · Describe · 4 marks

> In a woodland ecosystem, oak trees are eaten by caterpillars, which are in turn eaten by blue tits.

## Mark scheme (4 marks)

1. Producers (oak trees) photosynthesise / use light energy to make glucose / organic molecules
2. Primary consumers (caterpillars) eat / feed on producers to obtain energy / nutrients
3. Energy is transferred along the food chain when one organism eats another
4. Not all energy is transferred / energy is lost at each stage (e.g. as heat through respiration, in waste / uneaten material)

## Key terms

- [producers](https://www.gradenine.co.uk/glossary/producers)
- [primary consumers](https://www.gradenine.co.uk/glossary/primary-consumers)
- [food chain](https://www.gradenine.co.uk/glossary/food-chain)

## Related

- [Revision notes for WJEC GCSE Biology (Wales)](https://www.gradenine.co.uk/learn)
- [How to answer "Describe" 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/describe-the-roles-of-producers-and-c9ea18cb) · Published by Druglandscape Ltd.