Synaptic cleft

Definition

The synaptic cleft is the small gap between the presynaptic neuron and the postsynaptic cell where neurotransmission occurs. It allows for the transfer of chemical signals via neurotransmitters to propagate nerve impulses.

5 Must Know Facts For Your Next Test

1. The synaptic cleft typically measures about 20-40 nanometers in width.
2. Neurotransmitters released from synaptic vesicles cross the synaptic cleft to bind with receptors on the postsynaptic cell membrane.
3. Enzymes in the synaptic cleft can break down neurotransmitters to terminate the signal transmission.
4. Calcium ions play a crucial role in triggering neurotransmitter release into the synaptic cleft.
5. The efficiency and speed of neurotransmission across the synaptic cleft are essential for proper nervous system function.

Review Questions

• What is the primary function of the synaptic cleft?
• How do neurotransmitters travel across the synaptic cleft?
• Why is it important for enzymes to break down neurotransmitters in the synaptic cleft?

Related terms

Neuron: A specialized cell that transmits nerve impulses.

Neurotransmitter: Chemical substances that transmit signals across a synapse.

Synapse: The junction between two neurons or between a neuron and a target cell, facilitating neural communication.