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Synapses

Cells and control · Neurones and reflexes · note 3 of 5

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SynapsesSpec 2.13

A synapse is a gap between two neurones. The electrical impulse cannot cross the gap, so a chemical is used instead.

  1. An electrical impulse arrives at the end of the first neurone.
  2. The neurone releases a chemical called a neurotransmitter into the synapse.
  3. The neurotransmitter diffuses across the gap.
  4. It binds to receptors on the membrane of the next neurone.
  5. This triggers a new electrical impulse in the next neurone.
A synapse: an electrical impulse arrives at the end of the first neurone, vesicles release neurotransmitter into the gap, the neurotransmitter diffuses across and binds to receptors on the next neurone, which starts a new impulse.Tap to enlarge
At a synapse the neurotransmitter diffuses across the gap and binds to receptors on the next neurone.