The backflow of an action potential in the direction of initiation is prevented by ___________.
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the efflux of potassium at the Node of Ranvier; |
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a decrease in the threshold of excitation at the Node of Ranvier; |
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a shift in the threshold of excitation underneath the myelin sheath; |
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the influx of sodium underneath the myelin sheath; |
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none of the alternatives is correct; |
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