試題詳解

23. Why are action potentials usually conducted in one direction?
(A) The axon hillock has a higher membrane potential than the terminals of the axon.
(B) Voltage-gated K+ channels cause membrane potential overshoot after the action potential.
(C) The brief refractory period prevents reopening of voltage-gated Na+ channels.
(D) Voltage-gated channels for both Nat and K+ open in only one direction.