Voltage-gated Na+ channels are recovering from their refractory state, in a voltage-dependent way.

Voltage-gated Na⁺ channels are recovering from their refractory state, in a time-dependent way.

Voltage-gated Na+ channels are recovering from their refractory state, in a threshold-dependent way.

Voltage-gated Na+ channels are recovering from their refractory state, in a stimulus-dependent way.

Voltage-gated Na+ channels are recovering from their refractory state, in a step fashion way. from all being refractory to all being open.

Decreasing the axon diamater to conserve the current

Increasing the number of voltage-gated Na+ channels and decreasing the number of voltage-gated K+ channels

Increasing the length of the axon to allow for current to flow further

Increasing axon diameter and myelination of the axon

Shortening the le ngth of the axon to allow current to activate voltage-gated Na+ channels

During the ARP, although some voltage-gated Na+ channels can open, this is counterbalanced by an increased conductance to K⁺ ions across the membrane.

During the ARP, all voltage-gated Na⁺ channels are refractory and closed.

Neurons never receive a second very strong stimulus during the ARP to allow all the voltage-gate channels to open..

During the ARP, the Na⁺/K⁺ pump is too active to allow Na⁺ to depolarise the membrane to threshold for an AP.

During the ARP, only some voltage-gated Na⁺ channels are refractory and closed but these are the ones specifically responsible for APs.

Activation of both the K⁺ and Cl^- conductances.

Inactivation of both the Na⁺ and Cl^- conductances.

Inactivation of the Na⁺ conductance.

Activation of the K⁺ conductance.

Inactivation of the Cl^- conductance.