IGCSE Biology glossary
Relay neurone
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Definition
A short neurone found within the central nervous system (brain or spinal cord) that connects sensory neurones to motor neurones. In reflex arcs, the relay neurone transfers the impulse between the incoming sensory signal and the outgoing motor signal.
What to include in an exam answer
Relay neurones are only found in the CNS. They connect sensory neurones to motor neurones. Some sources call them interneurones. In a simple reflex arc, the relay neurone is in the spinal cord.
Example in context
State where relay neurones are found and their function (2 marks): Relay neurones are found in the central nervous system (brain or spinal cord). They connect sensory neurones to motor neurones, passing the impulse between them.
Related syllabus topic
Coordination & responseRelated terms
- Homeostasis
- Negative feedback
- Tropism
- Reflex arc
- ADH
- Insulin
- Glucagon
- Adrenaline
- Synapse
- Neurone
- Sensory neurone
- Motor neurone
- Receptor
- Effector
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- Iris
- Lens
- Retina
- Optic nerve
- Accommodation
- Type 1 diabetes
- Type 2 diabetes
- Hormones
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- Auxin
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- Vasoconstriction
- Vasodilation
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