PHYSIOLOGY
SYNAPTIC PHYSIOLOGY
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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the previous piece of membrane is in relative refractory
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the next piece of membrane is in relative refractory
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the previous piece of membrane is in absolute refractory
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the next piece of membrane is in absolute refractory
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Detailed explanation-1: -Second, the action potential can only travel in one direction – from the cell body towards the axon terminal – because a patch of membrane that has just undergone one action potential is in a “refractory period” and cannot undergo another.
Detailed explanation-2: -But action potentials move in one direction. This is achieved because the sodium channels have a refractory period following activation, during which they cannot open again. This ensures that the action potential is propagated in a specific direction along the axon.
Detailed explanation-3: -Action potentials travel in only one direction down an axon because potassium channels in the neuron are refractory and cannot be activated for a short time after they open and close.
Detailed explanation-4: -Explanation: Absolute refractory period occurs because of the inactivation of sodium channels. Since the sodium channels are inactivated, the neuron can’t depolarize and initiate another action potential.
Detailed explanation-5: -Why does regeneration of the action potential occur in one direction, rather than in two directions? The inactivation gates of voltage-gated K+ channels close in the node, or segment, that has just fired an action potential.