After a nerve impulse occurs, the neuron is temporarily less likely to fire because
A) the cell is still above its resting level.
B) potassium ions flow out of the neuron while the membrane gates are open.
C) acetylcholine acts as an inhibitor.
D) a positive after-potential has occurred.

Question

Quizplus · Accepted Answer

During a nerve impulse or action potential, sodium ions rush into the neuron, making the inside of the cell more positively charged relative to the outside. After the action potential, the neuron immediately begins to pump the excess sodium ions out while allowing potassium ions to flow out of the neuron through potassium channels. This results in the inside of the neuron becoming more negative again, known as a hyperpolarization. This after-potential makes the neuron temporarily less likely to fire again, which is known as the refractory period.

After a Nerve Impulse Occurs, the Neuron Is Temporarily Less