Which term describes the fatty coating that insulates an axon?

Which term describes the fatty coating that insulates an axon?

• A. Myelin
• B. Neurolemma
• C. Synapse
• D. Golgi apparatus

Answer: (A)

Myelin is the fatty coating that insulates an axon. This insulating sheath, formed by glial cells (oligodendrocytes in the CNS and Schwann cells in the PNS), prevents electrical leakage and enables rapid transmission of nerve impulses through saltatory conduction, where signals jump between gaps called nodes of Ranvier. The neurolemma is the Schwann cell’s outer membrane around the axon and relates to regeneration, not the insulating sheath itself. The synapse is the junction between neurons, and the Golgi apparatus is an internal cell organelle involved in protein processing. So the fatty insulating coating of the axon is myelin.

Myelin is the fatty coating that insulates an axon. This insulating sheath, formed by glial cells (oligodendrocytes in the CNS and Schwann cells in the PNS), prevents electrical leakage and enables rapid transmission of nerve impulses through saltatory conduction, where signals jump between gaps called nodes of Ranvier. The neurolemma is the Schwann cell’s outer membrane around the axon and relates to regeneration, not the insulating sheath itself. The synapse is the junction between neurons, and the Golgi apparatus is an internal cell organelle involved in protein processing. So the fatty insulating coating of the axon is myelin.