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)None of the above could happen.

Question

Quizplus · Accepted Answer

Without nodes of Ranvier, the signal would not be renewed by the opening of more sodium channels, which means it would fade over time. The myelin sheath would insulate the axon, preventing the entry of ions necessary for depolarization, so an action potential couldn't be generated at the axon hillock. Therefore, the action potential would not be propagated nearly instantaneously to the synapse.

What Would Probably Happen If a Long Neuron Had One