(a)[4]
Describe how the arrival of an action potential at a presynaptic neurone can lead to acetylcholine being released into the synaptic cleft.
(b)[2]
Lidocaine is a local anaesthetic drug that blocks voltage-gated $\text{Na}^+$ channels in the postsynaptic membrane of a synapse. Explain the effect of lidocaine on the postsynaptic neurone.
(c(i))[3]
Using Fig. 8.1, name structures A, B and C.
(c(ii))[2]
Outline the role of structure A in the transmission of nerve impulses.
(c(iii))[4]
Explain why the structures labelled C are required in a neuromuscular junction.