What process increases insulation around axons to speed transmission?

• A. Pruning
• B. Neurons
• C. Myelination
• D. Cerebellum

Answer: (C)

Myelination speeds neural transmission by insulating axons. The myelin sheath, produced by glial cells (oligodendrocytes in the central nervous system and Schwann cells in the peripheral nervous system), wraps around axons to increase membrane resistance and decrease capacitance. This insulation prevents current from leaking out and allows the electrical signal to propagate quickly by jumping between gaps called nodes of Ranvier—a mechanism known as saltatory conduction. The result is much faster and more efficient communication along nerve fibers.

Pruning, on the other hand, removes excess synaptic connections during development to refine networks, which doesn’t speed up conduction along an axon. Neurons are the cells that transmit signals, not the process of insulation. The cerebellum is a brain region involved in coordination, not the process that insulates axons.