What keeps a nerve action potential from flowing "backward" in a neuron?
A)Schwann cells keep action potentials flowing one direction
B)Sodium ions can only move toward a synapse
C)Chemical synapse receptors form a one-way gate and there is a refractory period after sodium ions are pumped back out
D)The axon and dendrite have completely different membrane structures
E)All of the choices are correct

Question

Quizplus · Accepted Answer

Chemical synapse receptors form a one-way gate and there is a refractory period after sodium ions are pumped back out. This means that once an action potential reaches the end of the axon and enters a synapse, the receptors on the next neuron or muscle fiber can only be activated by neurotransmitters released from the first neuron. After the neurotransmitters are released, there is a brief period of time where the sodium channels on the first neuron are closed and unable to open again, ensuring that the action potential can only continue in one direction.

What Keeps a Nerve Action Potential from Flowing "Backward" in a Neuron