PATHOLOGY MCQ
NERVOUS SYSTEM
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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To maintain temperature
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To improve conductivity
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To protect the axon
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To release neurotransmitters
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Detailed explanation-1: -By acting as an electrical insulator, myelin greatly speeds up action potential conduction (Figure 3.14). For example, whereas unmyelinated axon conduction velocities range from about 0.5 to 10 m/s, myelinated axons can conduct at velocities up to 150 m/s.
Detailed explanation-2: -Myelin has properties of low capacitance and high electrical resistance which means it can act as an insulator. Therefore, myelin sheaths insulate axons to increase the speed of electrical signal conduction. This allows myelinated axons to conduct electrical signals at high speeds.
Detailed explanation-3: -The purpose of the myelin sheath is to increase the speed of transmission by acting as an electrical insulator. In non-myelinated axons, the action potential must propagate continuously along the plasma membrane.