What is the purpose of the myelin sheath?
A) Protects the nerve from damage
B) Speeds electrical conduction
C) Produces Schwann cells
D) Secretes neurotransmitters
B
Feedback:
Long nerves are myelinated: They have a myelin sheath that speeds electrical conduction and protects the nerves from the fatigue that results from frequent formation of action potentials, not from damage. Although myelin sheaths have Schwann cells, they do not produce these cells and the myelin sheath does not secrete neurotransmitters.
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