What is the function of the myelin sheath?

The myelin sheath plays a crucial role in the nervous system by increasing the speed of signal conduction along neurons. This sheath is composed of lipids and proteins and wraps around the axons of certain neurons, forming an insulating layer.

Due to the myelin sheath's insulation, electrical impulses can jump between the gaps in the sheath, known as nodes of Ranvier, in a process called saltatory conduction. This allows the action potential to travel much faster compared to unmyelinated fibers, where the impulses must travel continuously along the entire length of the axon. As a result, myelinated neurons can transmit signals more efficiently and rapidly, which is essential for proper nervous system function.

While supporting neuron shape and structure is essential for overall neuron health, it is not the primary role of the myelin sheath. Similarly, initiating action potentials and transmitting neurotransmitters occur through different processes and structures within the neuron. Thus, the primary function of the myelin sheath is specifically aimed at enhancing the speed of signal conduction.