PHYSIOLOGY
MUSCLE CONTRACTION
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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calcium ions diffusing out of the cell
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sodium ions diffusion out of the cell
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potassium ions diffusing out of the cell
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None of the above
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Detailed explanation-1: -Depolarization is caused when positively charged sodium ions rush into a neuron with the opening of voltage-gated sodium channels. Repolarization is caused by the closing of sodium ion channels and the opening of potassium ion channels.
Detailed explanation-2: -During repolarization, potassium ions move out of the cell via potassium channels. This movement is down the concentration gradient to restore the charges across the cell membrane.
Detailed explanation-3: -In the nerve cells, this generates the electrical potential that allows the conduction of nerve impulses. When potassium leaves the cell, it restores repolarization to the cell, which allows the nerve impulse to progress. This electrical potential gradient helps generate muscle contractions and regulates the heartbeat.