Describe the sequence of events which allows information to pass from one neurone to the next neurone across a cholinergic synapse. (6 marks)
(1) An impulse causes calcium ions to enter the axon. (2) Vesicles fuse with the presynaptic membrane. (3) This causes the release of acetylcholine. (4) Acetylcholine diffuses across the synaptic cleft. (5) It binds with receptors on the postsynaptic membrane. (6) Sodium ions enter the neurone, causing depolarisation of the postsynaptic membrane. (7) If above threshold, a nerve impulse is produced.Note: there are 7 mark points for 6 available marks, if you put any 6 of the above you will get full marks!
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