Where are nodes of Ranvier located?

Where are nodes of Ranvier located?

• A. Gaps in the myelin sheath along the axon
• B. In the dendrites
• C. At synapses
• D. In the soma

Answer: (A)

Nodes of Ranvier are gaps in the myelin sheath along the axon. These exposed regions are rich in voltage-gated sodium channels, so the action potential is regenerated at each node, allowing rapid, saltatory conduction along myelinated fibers. They occur along axons in both the CNS and PNS (between myelin segments produced by oligodendrocytes or Schwann cells). They are not located in dendrites, at synapses, or in the soma, which is why the correct location is along the axon between myelinated segments.

Nodes of Ranvier are gaps in the myelin sheath along the axon. These exposed regions are rich in voltage-gated sodium channels, so the action potential is regenerated at each node, allowing rapid, saltatory conduction along myelinated fibers. They occur along axons in both the CNS and PNS (between myelin segments produced by oligodendrocytes or Schwann cells). They are not located in dendrites, at synapses, or in the soma, which is why the correct location is along the axon between myelinated segments.