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Myelin Sheath

APBIO-PEIZNR

A typical neuron has a myelin sheath insulating its axon. It is formed from cells known as Schwann cells. Some nervous system disorders, such as adrenoleukodystrophy, result from the deterioration of the myelin sheath.

Which of the following explains why the myelin sheath is important for the correct functioning of the neuron?

A

The surface of the myelin sheath carries many receptors for neurotransmitters, allowing the neuron to receive chemical signals.

B

Gaps in the myelin sheath allow for saltatory conduction, where electrical impulses jump from one covered area to another.

C

The myelin sheath blocks external signals that originate outside the neuron, preventing interference with nervous signal transmission.

D

The complete coverage of the axon by the myelin sheath channels all electrical impulses directly through the neuron, resulting in faster signal transmission.