(a)[4]
Describe the nervous system parts that are shown in each diagram.
(b(i))[1]
Name the junction that is shown in Fig. 3.2.
(b(ii))[1]
Draw an arrow on Fig. 3.2 to indicate the direction in which an impulse will travel.
(b(iii))[1]
In Fig. 3.2, the separation between the two neurones is $0.00003\,\text{mm}$. State this distance in units of $\mu\text{m}$.
(c)[3]
Nicotine is a chemical found in cigarette smoke. A nicotine molecule has a similar shape to a neurotransmitter molecule. Suggest and explain the effect of nicotine at the junctions between neurones.