Why are action potentials usually conducted in one direction?
A) The nodes of Ranvier conduct potentials in one direction.
B) The brief refractory period prevents reopening of voltage-gated Na+ channels.
C) The axon hillock has a higher membrane potential than the terminals of the axon.
D) Ions can flow along the axon in only one direction.
E) Voltage-gated
Answer: B
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