# Explain how a nerve impulse is transmitted across a synapse from one neurone to the next.

> Cambridge International IGCSE Biology (0610) — 14.1 Nervous control in humans · Explain · 4 marks

## Mark scheme (4 marks)

1. Nerve impulse arrives at the presynaptic neurone, causing synaptic vesicles to fuse with the membrane
2. Neurotransmitters are released into the synaptic cleft
3. Neurotransmitters diffuse across the synaptic cleft and bind to receptors on the postsynaptic neurone
4. This triggers / generates a new nerve impulse in the postsynaptic neurone, ensuring the impulse can only travel in one direction

## Key terms

- [synapse](https://www.gradenine.co.uk/glossary/synapse)

## Related

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Source: [GradeNine](https://www.gradenine.co.uk/q/explain-how-a-nerve-impulse-is-e7c337af) · Published by Druglandscape Ltd.