Which glial cell type is primarily responsible for myelination in the central nervous system?

Which glial cell type is primarily responsible for myelination in the central nervous system?

• A. Schwann cells
• B. Oligodendrocytes
• C. Ependymal cells
• D. Retina

Answer: (B)

Oligodendrocytes are the cells in the central nervous system that provide the insulating myelin sheath around axons. They can extend their processes to wrap segments of multiple axons, creating the myelin layers that speed up electrical conduction through saltatory conduction. This is distinct from Schwann cells, which perform the same insulating role in the peripheral nervous system by wrapping myelin around a single axon segment. Ependymal cells line the brain ventricles and help produce and circulate cerebrospinal fluid, not myelination. The retina is neural tissue and not a source of myelinating glia in the CNS.

Oligodendrocytes are the cells in the central nervous system that provide the insulating myelin sheath around axons. They can extend their processes to wrap segments of multiple axons, creating the myelin layers that speed up electrical conduction through saltatory conduction. This is distinct from Schwann cells, which perform the same insulating role in the peripheral nervous system by wrapping myelin around a single axon segment. Ependymal cells line the brain ventricles and help produce and circulate cerebrospinal fluid, not myelination. The retina is neural tissue and not a source of myelinating glia in the CNS.