Which component insulates axons and boosts action potential conduction speed?

Which component insulates axons and boosts action potential conduction speed?

• A. Myelin sheath
• B. Cell body (soma)
• C. Terminal buttons
• D. CSF

Answer: (A)

Insulating the axon with a myelin sheath speeds up how signals travel along the nerve fiber. Myelin wraps the axon in segments, with small gaps called Nodes of Ranvier. The electrical signal hops from node to node in a process called saltatory conduction, making transmission much faster than if the axon were unmyelinated. This insulation also raises membrane resistance and lowers capacitance, reducing ion leakage and allowing depolarization to reach the next node quickly. In the central nervous system, myelin is produced by oligodendrocytes; in the peripheral nervous system, by Schwann cells. The soma, terminal buttons, and cerebrospinal fluid don’t provide this insulating, speed-enhancing function.

Insulating the axon with a myelin sheath speeds up how signals travel along the nerve fiber. Myelin wraps the axon in segments, with small gaps called Nodes of Ranvier. The electrical signal hops from node to node in a process called saltatory conduction, making transmission much faster than if the axon were unmyelinated. This insulation also raises membrane resistance and lowers capacitance, reducing ion leakage and allowing depolarization to reach the next node quickly. In the central nervous system, myelin is produced by oligodendrocytes; in the peripheral nervous system, by Schwann cells. The soma, terminal buttons, and cerebrospinal fluid don’t provide this insulating, speed-enhancing function.