The answer is true.
The myelin sheath covers many axons in central nervous system (CNS) ( by oligodendrocytes) and in the peripheral nervous system (PNS) (by Schwann cells). Their function is to insulate axons and to increase the speed at which information travels from one nerve cell to another.
Nerve conduction velocity is specific to each individual and depend largely onboth an axon's diameter and the level to which that axon is myelinated.
