Myelin speeds up neural transmission along which neural structure?

Myelin speeds up neural transmission along which neural structure?

• A. Slows it down
• B. Alters direction
• C. Stops it
• D. Speeds it up

Answer: (D)

Myelin speeds neural transmission along the axon by enabling saltatory conduction. The myelin sheath insulates the axon, produced by oligodendrocytes in the CNS and Schwann cells in the PNS, which increases membrane resistance and decreases membrane capacitance. This keeps depolarizing current from leaking across the membrane, so the action potential is regenerated mainly at the nodes of Ranvier and effectively “jumps” from node to node. That leapfrogging dramatically increases conduction speed on myelinated axons. So the neural structure involved is the axon, and its transmission is sped up.

Myelin speeds neural transmission along the axon by enabling saltatory conduction. The myelin sheath insulates the axon, produced by oligodendrocytes in the CNS and Schwann cells in the PNS, which increases membrane resistance and decreases membrane capacitance. This keeps depolarizing current from leaking across the membrane, so the action potential is regenerated mainly at the nodes of Ranvier and effectively “jumps” from node to node. That leapfrogging dramatically increases conduction speed on myelinated axons. So the neural structure involved is the axon, and its transmission is sped up.