Another example of a synthesis reaction is the formation of sodium chloride (table salt). Because of the very high reactivities of sodium metal and chlorine gas, this reaction releases a tremendous amount of heat and light energy.
Schwann cells make myelin in the peripheral nervous system (PNS: nerves) and oligodendrocytes in the central nervous system (CNS: brain and spinal cord). In the PNS, one Schwann cell forms a single myelin sheath (Figure 1A).
Oligodendrocytes-neuroglial cells of ectodermal origin that myelinate axons in the central nervous system, and forms the white matter of the central nervous system (unmyelinated axons are grey matter). Plexus-networks of nerves or blood vessels formed before nerves are distributed to the muscles.