HISTOLOGY
NERVOUS TISSUE
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Na+ flooding into the cell; Na+ flooding out of the cell.
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K+ flooding into the cell; K+ flooding out of the cell.
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Na+ flooding into the cell; K+ flooding out of the cell.
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K+ flooding into the cell; Na+ flooding out of the cell.
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Detailed explanation-1: -Depolarization is caused by a rapid rise in membrane potential opening of sodium channels in the cellular membrane, resulting in a large influx of sodium ions. Membrane Repolarization results from rapid sodium channel inactivation as well as a large efflux of potassium ions resulting from activated potassium channels.
Detailed explanation-2: -Phase three is repolarization, involving the closing of Ca2+ channels, blocking the flow of Ca2+ ions. Voltage-gated K+ channels open, allowing for efflux of K+ ions. This efflux of cation contributes to a rapid decrease of membrane potential from +10 mV to-60mV.
Detailed explanation-3: -The depolarization is brought about by the entry of sodium and calcium ions that results from the opening of membrane channels.