試題詳解

48. What would probably happen if a long neuron had one continuous myelin sheath down the length of the axon with no nodes of Ranvier?
(A)The action potential would be propagated nearly instantaneously to the synapse.
(B)There could be no action potential generated at the axon hillock.
(C) The signal would fade because it is not renewed by the opening of more sodium channels.
(D) Only potassium could move across the membrane, but not sodium.