<P> Myelin is a lipid - rich ( fatty ) substance formed in the central nervous system ( CNS ) by glial cells called oligodendrocytes , and in the peripheral nervous system ( PNS ) by Schwann cells . Myelin insulates nerve cell axons to increase the speed at which information ( encoded as an electrical signal ) travels from one nerve cell body to another ( as in the CNS ) or , for example , from a nerve cell body to a muscle ( as in the PNS ) . The myelinated axon can be likened to an electrical wire ( the axon ) with insulating material ( myelin ) around it . However , unlike the plastic covering on an electrical wire , myelin does not form a single long sheath over the entire length of the axon . Rather , each myelin sheath insulates the axon over a long section and each axon comprises multiple long myelinated sections separated from each other by short gaps . Each myelin sheath is formed by the concentric wrapping of an oligodendrocyte or Schwann cell process around the axon . </P>
<P> Myelin is a lipid - rich ( fatty ) substance formed in the central nervous system ( CNS ) by glial cells called oligodendrocytes , and in the peripheral nervous system ( PNS ) by Schwann cells . Myelin insulates nerve cell axons to increase the speed at which information ( encoded as an electrical signal ) travels from one nerve cell body to another ( as in the CNS ) or , for example , from a nerve cell body to a muscle ( as in the PNS ) . The myelinated axon can be likened to an electrical wire ( the axon ) with insulating material ( myelin ) around it . However , unlike the plastic covering on an electrical wire , myelin does not form a single long sheath over the entire length of the axon . Rather , each myelin sheath insulates the axon over a long section and each axon comprises multiple long myelinated sections separated from each other by short gaps . Each myelin sheath is formed by the concentric wrapping of an oligodendrocyte or Schwann cell process around the axon . </P>
the part of peripheral nerve tissue that forms the myelin sheath is the
the part of peripheral nerve tissue that forms the myelin sheath is the
Schwann cells
Schwann cells