Which glial cell forms the myelin sheath in the central nervous system and can wrap around multiple axons?

Which glial cell forms the myelin sheath in the central nervous system and can wrap around multiple axons?

• A. Schwann cells
• B. Oligodendrocytes
• C. Astrocytes
• D. Microglia

Answer: (B)

CNS myelination is carried out by oligodendrocytes, which can wrap multiple axons. A single oligodendrocyte extends several processes, each of which wraps around a segment of an axon to form a myelin sheath. This allows many axons in the central nervous system to be myelinated by a relatively small number of glial cells, speeding up signal transmission through saltatory conduction. In the peripheral nervous system, Schwann cells form myelin but each Schwann cell myelinates only a single axon segment. Astrocytes provide support and maintain the environment around neurons, while microglia act as immune cells within the CNS. Thus, the cell that forms the CNS myelin sheath and can wrap around multiple axons is the oligodendrocyte.

CNS myelination is carried out by oligodendrocytes, which can wrap multiple axons. A single oligodendrocyte extends several processes, each of which wraps around a segment of an axon to form a myelin sheath. This allows many axons in the central nervous system to be myelinated by a relatively small number of glial cells, speeding up signal transmission through saltatory conduction. In the peripheral nervous system, Schwann cells form myelin but each Schwann cell myelinates only a single axon segment. Astrocytes provide support and maintain the environment around neurons, while microglia act as immune cells within the CNS. Thus, the cell that forms the CNS myelin sheath and can wrap around multiple axons is the oligodendrocyte.