What is the function of the myelin sheath on a neuron's axon?
Answer and explanation
Correct answer: A. It insulates the axon so impulses jump between nodes of Ranvier
- Step 1: Myelin is a fatty insulating layer with gaps called nodes of Ranvier. Step 2. Impulses jump from node to node (saltatory conduction), which speeds transmission. Answer: It insulates the axon so impulses jump between nodes of Ranvier. Why not the others: Vesicles store transmitter; the Na/K pump is a membrane protein; the synaptic cleft is the gap.
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