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Myelin limits the movement of ions across the axon membrane, so the action potential "jumps" from node to node along the axon. This is an example of what type of propagation?

User Joe Doyle
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Final answer:

In myelinated neurons, the action potential jumps from node to node along the axon membrane, due to the presence of nodes of Ranvier and clustering of Na+ and K+ ion channels at these nodes.

Step-by-step explanation:

In myelinated neurons, ion flows occur only at the nodes of Ranvier. As a result, the action potential signal "jumps" along the axon membrane from node to node rather than spreading smoothly along the membrane, as they do in axons that do not have a myelin sheath.

This is due to a clustering of Na+ and K+ ion channels at the Nodes of Ranvier. Unmyelinated axons do not have nodes of Ranvier, and ion channels in these axons are spread over the entire membrane surface.

User Damian Schenkelman
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