(a)[4]
Name the parts of the neurone marked A, B, C and D.
(b)[2]
Explain how the myelin sheath increases the speed of conduction of nerve impulses.
(c)[2]
Fig. 8.2 shows how the membrane potential of a sensory neurone changes when the receptor cells are stimulated. Fig. 8.3 shows the strengths of the stimuli applied to these receptor cells. Using Fig. 8.2 and Fig. 8.3, describe how the strength of the stimulus is related to the action potential produced.