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Restoring Resting State


The nervous system carries electrical signals throughout the body. It brings afferent impulses in from the environment and sends efferent impulses out from the brain and spinal cord to effectors, such as muscles and glands. The chemical signals of neurotransmitters move across the synapses and are transformed into electrical signals as they pass through the neuron.

By Pearson Scott Foresman [Public domain], via Wikimedia Commons

After an electrical nerve impulse is produced by a neuron, which of the following returns the neuron to its resting state?


$Na^+/K^+$ pumps transporting ions across the membrane.


$Na^+$ channels producing local depolarization.


$K^+$ channels producing local hyperpolarization.


$Na^+/K^+$ pumps preventing ion transport.