# Describe the roles of the central nervous system (CNS) and effectors in producing a response to a stimulus.

> WJEC GCSE Biology (Wales) — 2.5.1 The nervous system · Describe · 4 marks

## Mark scheme (4 marks)

1. The CNS is made up of the brain and spinal cord
2. The CNS receives / processes information (from receptors / sensory neurones)
3. The CNS sends impulses (via motor neurones) to effectors
4. Effectors (muscles or glands) carry out the response / produce the action

## Key terms

- [central nervous system](https://www.gradenine.co.uk/glossary/central-nervous-system)
- [effector](https://www.gradenine.co.uk/glossary/effector)
- [stimulus](https://www.gradenine.co.uk/glossary/stimulus)

## 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-the-central-1ff10a2b) · Published by Druglandscape Ltd.