synaptic cleft
Quick Summary
The synaptic cleft is the tiny gap between two neurons, or between a neuron and a muscle or gland cell, where nerve impulses are transmitted. This transmission is typically chemical, involving the release of neurotransmitters from the presynaptic terminal of one neuron into the synaptic cleft.12
The presynaptic terminal contains vesicles filled with neurotransmitters and mitochondria for energy. When a nerve impulse arrives, these vesicles fuse with the presynaptic membrane, releasing neurotransmitters that diffuse across the synaptic cleft. On the other side, the postsynaptic membrane has receptors that bind these neurotransmitters, initiating a response in the receiving cell by opening ion channels. This can either excite the cell, potentially triggering a new nerve impulse (action potential), or inhibit it. Neurotransmitters are then quickly deactivated by enzymes or recycled by the presynaptic membrane.12
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neurotransmitterNeurotransmitter signaling…by a gap called the synaptic cleft. The synaptic cleft, presynaptic terminal, and receiving dendrite of the next cell together form a junction known as the synapse.
Read More…by a gap called the synaptic cleft. The synaptic cleft, presynaptic terminal, and receiving dendrite of the next cell together form a junction known as the synapse.
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nervous systemAxon…by a gap called the synaptic cleft, across which neurotransmitters diffuse when released from the vesicles. In nerve-muscle junctions the synaptic cleft contains a structure called the basal lamina, which holds an enzyme that destroys neurotransmitters and thus regulates the amount that reaches the postsynaptic receptors on the receiving cell.…
Read More…by a gap called the synaptic cleft, across which neurotransmitters diffuse when released from the vesicles. In nerve-muscle junctions the synaptic cleft contains a structure called the basal lamina, which holds an enzyme that destroys neurotransmitters and thus regulates the amount that reaches the postsynaptic receptors on the receiving cell.…
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