What role does the neurilemma play in the structure of the neuron?

• A. Protects the neuron’s nucleus
• B. Provides insulation for the axon
• C. Facilitates nerve impulse conduction
• D. Serves as the outer membrane of Schwann cells

Answer: (D)

The neurilemma, also known as the neurolemma, is a critical component of the peripheral nervous system. It serves as the outer membrane of Schwann cells, which wrap around the axons of peripheral neurons. This structure is essential for several reasons, including its protective role in allowing for the regeneration of axons after injury, which is a notable difference from central nervous system neurons. The Schwann cells themselves produce myelin, which segments the axon into myelinated sections that can significantly enhance the speed of nerve impulse conduction.

In the context of the other options, while the neurilemma contributes to aspects of neuron function, it specifically encapsulates the axons formed by Schwann cells rather than directly providing insulation or facilitating nerve impulse conduction on its own. In this sense, recognizing the neurilemma’s role as the outer membrane reinforces the understanding of both peripheral nerve structure and the distinct differences in neural regeneration between peripheral and central systems.