Myelination is the answer.
Myelin is an insulating layer or sheath formed around nerves, including the brain and spinal cord. It is composed of protein and fat. This myelin sheath allows electrical impulses to be transmitted quickly and efficiently along nerve cells. When myelin is damaged, these impulses slow down.
CNS myelin is produced by a special cell called oligodendrocytes. PNS myelin is produced by Schwann cells. Although the two types of myelin are chemically different, they both perform the same function and enable the efficient transmission of nerve impulses down axons
Myelin is formed by the innermost sheet-like glial process that contacts axons in the PNS (peripheral nervous system) and CNS. Axons spiral around the axons and spin out several layers of overlapping membranes.
Learn more about myelin sheath here:https://brainly.com/question/690266
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