Describe the events of the cholinergic synapse
Action potential reaches neurone.Voltage gated Ca²+ channels in the presynaptic membrane open.Calcium ions flow in, pushing acetylcholine filled vesicles to the presynaptic membrane.Vesicles fuse with the membrane.Acetylcholine enters synaptic cleft by exocytosis. Acetylcholine diffuses across synaptic cleft and attached to receptor protein on postsynaptic membrane .In response, postsynaptic membrane's permeability to Na+ ions increases. Sodium ions diffuse in, leading to the depolarisation of post synaptic membrane. Thus, action potential is generated.Acetylcholine is broken down by the enzyme acetylcholinesterase. Choline flows back into presynaptic neurone.
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