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The Nodes of Ranvier serve a critical role in the conduction of electrical impulses along myelinated neurons. These nodes are interruptions in the myelin sheath, which is an insulating layer that surrounds the axon of the neuron. One of the primary functions of the Nodes of Ranvier is to concentrate ion channels, particularly voltage-gated sodium channels.

When an action potential travels along a myelinated axon, it jumps from one Node of Ranvier to the next in a process called saltatory conduction. This jumping significantly increases the speed of signal transmission compared to unmyelinated fibers, where the action potential must propagate continuously along the entire length of the neuron. Although the presence of myelin is crucial for improving signal speed, the function of the Nodes of Ranvier is specifically tied to the concentration of ion channels that facilitate rapid depolarization and repolarization during the action potential.

Thus, while the Nodes of Ranvier contribute to the overall faster transmission of signals and the myelin insulates the neuron, their primary function centers around the concentration of ion channels that enable swift electrical signaling.