A fatty insulating material that surrounds some nerve fibers is called a

A fatty insulating material that surrounds some nerve fibers is called a

• A. Myelin Sheath
• B. Neurilemma
• C. Peripheral Nerves
• D. Muscle Tissue

Answer: (A)

The fatty insulating material around some nerve fibers is the myelin sheath. It wraps around axons and is rich in lipids, which helps speed up electrical impulses by allowing them to jump from one node of Ranvier to the next (saltatory conduction). In the peripheral nervous system, Schwann cells form this insulation; in the central nervous system, oligodendrocytes do. Neurilemma is the outer layer of Schwann cells around the myelin sheath and the nerve fiber, not the fatty insulation itself.

The fatty insulating material around some nerve fibers is the myelin sheath. It wraps around axons and is rich in lipids, which helps speed up electrical impulses by allowing them to jump from one node of Ranvier to the next (saltatory conduction). In the peripheral nervous system, Schwann cells form this insulation; in the central nervous system, oligodendrocytes do. Neurilemma is the outer layer of Schwann cells around the myelin sheath and the nerve fiber, not the fatty insulation itself.