Question: Q45. Why do neurons generate an action potential, instead of simply relying on the opening of ion…

Q45. Why do neurons generate an action potential, instead of
simply relying on the opening of ion channels near the stimulus
site to transmit information?

Because without the action potential, changes in
V_m at the stimulus site might not reach the
axon terminal.Because without the action potential, the neuron
would not depolarize.Because action potentials help the body keep
ion concentrations at appropriate levels.Because without the action
potential, the neuron would not return to resting potential.

Q47. Why does Na⁺ enter the cell during the action
potential?

Because the Na⁺ channels are open and only let
Na⁺ move from outside to inside.Because the action
potential pulls positive ions into the cell while Na⁺
and K⁺ channels are open.Because Na⁺ channels
are open and allow Na⁺ ions to move down the length of
the axon to produce neurotransmitter at the axon terminal.Because
Na⁺ channels are open and there is a higher
concentration of Na⁺ outside of the neuron than
inside.

Q48. Which statement below is TRUE about the voltage-gated
Na⁺ channels during the action potential?

The voltage-gated Na⁺ channels are open the entire
time that the neuron is depolarized (when V_m is
above resting potential).The voltage-gated Na⁺ channels
open after the voltage-gated K⁺ channels.The
voltage-gated Na⁺ channels open to restore
V_m to the resting potential after the action
potential peak.The voltage-gated Na⁺ channels are open
when V_m is rapidly increasing during the action
potential.