PATHOLOGY MCQ
NERVOUS SYSTEM
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Ploarized
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Depolarized
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Repolarization
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Refractory Period
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Detailed explanation-1: -A neuron at rest is negatively charged: the inside of a cell is approximately 70 millivolts more negative than the outside (−70 mV, note that this number varies by neuron type and by species).
Detailed explanation-2: -The relative excess of positive charges outside and negative charges inside the membrane of a nerve cell at rest is maintained because the lipid bilayer acts as a barrier to the diffusion of ions, and give rise to an electrical potential difference, which ranges from about 60 to 70 mV.
Detailed explanation-3: -The inside of the neuron is more negatively charged than the outside. Figure 4.1. For a typical neuron at rest, sodium, chloride, and calcium are concentrated outside the cell, whereas potassium and other anions are concentrated inside. This ion distribution leads to a negative resting membrane potential.