What wraps themselves around axons to insulate them?

• A. Schwann cells wrap themselves around axons
• B. Myelin sheath
• C. Dendrites
• D. Nucleus

Answer: (A)

Schwann cells in the peripheral nervous system wrap themselves around axons to form the myelin sheath. This wrapping creates an insulating layer that reduces current leakage and speeds up nerve impulses, enabling saltatory conduction where the signal jumps between nodes of Ranvier. Dendrites are receptive extensions, not insulators; the nucleus is the cell’s control center. The myelin sheath is the insulating layer itself, produced by Schwann cells wrapping around the axon.