Answer: Oligodendrocytes and schawn cells.
Step-by-step explanation:
Oligodendrocytes are form of gilial cells that is found in the Central nervous system. Oligodendrocytes secrete Myelin sheath around the axon of nerve fibres. They provide support and insulation to the Central nervous system.
Schawn cells are types of gilial cells found in the peripheral nervous system. They are also called neurilimma. They produce myelin sheath around the axon of neurons. They support nerve regeneration .