What is the absolute refractory period? Choose the correct option
A) The period when the firing frequency is at about 1000 Hz.
B) The time period of 1 msec after one action potential is initiated and before the next one is initiated.
C) The period when it is difficult to initiate another action potential for several milliseconds due to sodium channel inactivation.
D) The period when the membrane potential stays hyperpolarized until the voltage-gated potassium channels close.
Ans: B
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