A nerve impulse is caused by
A) the movement of a sodium ion all the way from dendrite to axon tip.
B) the movement of a potassium ion all the way from dendrite to axon tip.
C) the movement of sodium ions from a dendrite to an axon tip and the movement of potassium ions from the an axon tip to a dendrite.
D) a change in the difference in positive and negative ions on the outer and inner surfaces of the neuron membrane, a change that opens adjacent channels and propagates its flow.
E) a change in the difference in sugar molecules on the outer and inner surfaces of the neuron membrane that opens adjacent channels.

Question

Quizplus · Accepted Answer

A nerve impulse is caused by a change in the difference in positive and negative ions on the outer and inner surfaces of the neuron membrane, which causes adjacent ion channels to open and allow the flow of ions, propagating the impulse down the axon. Sodium and potassium ions are involved in this process, but they do not move all the way from dendrite to axon tip.

A Nerve Impulse Is Caused by