What is the primary benefit of the myelin sheath around axons?

The myelin sheath is primarily composed of lipid-rich material that surrounds the axons of many neurons. Its most significant function is to act as an insulator, which allows electrical impulses (or action potentials) to travel more rapidly along the axon. This increased speed of signal transmission is achieved through a process known as saltatory conduction, where the impulses jump between the gaps in the myelin sheath called nodes of Ranvier. This efficient transmission is critical for the proper functioning of the nervous system, enabling quicker communication between neurons and facilitating swift reflex responses and processing of sensory information.

While the myelin sheath does offer some level of protection to the axon and contributes to the overall health of neurons, its primary role is to enhance the speed at which signals are transmitted, making this choice the most accurate.