Axons insulated by a(n) are able to conduct impulses faster that those not so insulated.

Much like the insulation around the wires in electrical systems, glial cells form a membraneous sheath surrounding axons called myelin, thereby insulating the axon. This myelination, as it is called, can greatly increase the speed of signals transmitted between neurons (known as action potentials).

Explanation:

for more pls visit

https://www.nature.com/scitable/topicpage/myelin-a-specialized-membrane-for-cell-communication-14367205/

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