[Campbell Biology P.1125] Which of the following statements correctly describes a characteris... | Practice Question
Which of the following statements correctly describes a characteristic of action potential propagation and information encoding in neurons?
A: Action potentials propagate backward due to the sustained activation of voltage-gated sodium channels.
B: The strength of an input signal is primarily encoded by the amplitude of the action potential.
C: During the refractory period, the axon membrane is temporarily unresponsive, preventing action potentials from traveling backward toward the cell body.
D: Neurons encode stronger signals by decreasing the frequency of action potentials.
Explanation
The refractory period ensures unidirectional propagation of action potentials by making the membrane temporarily unresponsive. The frequency, not the amplitude, of action potentials encodes the strength of a signal.