Which cell type forms the myelin sheath around peripheral nerves?

• A. Neurones
• B. Schwann Cells
• C. Oligodendrocytes
• D. Microglia

Answer: (B)

The cell type that forms the myelin sheath around peripheral nerves is the Schwann cell. In the peripheral nervous system, Schwann cells wrap themselves around axons in segments, laying down layers of membrane to create the myelin sheath. This insulation speeds up nerve impulses through saltatory conduction, where signals jump from one node of Ranvier to the next. Other options aren’t correct here: neurones are the nerve cells themselves, not the myelinating cells; oligodendrocytes form myelin in the central nervous system (brain and spinal cord) rather than in the periphery; and microglia are immune-support cells within the CNS. So, for peripheral nerves, Schwann cells are the responsible myelinating cells.