What does the Node of Ranvier refer to?

The Node of Ranvier refers specifically to the gaps or interruptions that occur between the segments of myelin sheaths along an axon. Myelin, which is produced by cells such as oligodendrocytes in the central nervous system and Schwann cells in the peripheral nervous system, acts as an insulating layer around the axon, facilitating rapid transmission of electrical signals. The Nodes of Ranvier play a crucial role in saltatory conduction, where the action potential "jumps" from one node to the next, significantly increasing the speed of signal transmission along the neuron compared to unmyelinated fibers. This unique structural feature is key for efficient neuronal communication, enabling quick responses in the nervous system.