What is the conduction of an action potential at the Nodes of Ranvier called?

An action potential in a nerve fiber is generated when the outer surface is positive and the inner surface is negative,and the membrane potential is reversed because...

Select the correct option for the permeability of the axonal membrane in a resting state for $K^{+}$,$Na^{+}$,and negatively charged proteins.

The depolarization of nerve membrane takes place through influx of . . . . . . ions.

Given is the diagrammatic representation of impulse conduction through an axon (at points $A$ and $B$). View the diagram and arrange the steps of impulse conduction.
$I.$ The polarity of the membrane at site $A$ is reversed and depolarized,i.e.,the outer surface becomes negatively charged and the inner side becomes positively charged,generating a nerve impulse.
$II.$ $A$ stimulus causes a disturbance to the membrane at site $A$ of the nerve fibre,resulting in the leakage of $Na^+$ ions inside the nerve fibre.
$III.$ On the outer surface,current flows from site $B$ to site $A$ to complete the circuit of current flow. Hence,the polarity at the site is reversed,and an action potential is generated at site $B$. The impulse (action potential) generated at site $A$ arrives at site $B$. The sequence is repeated along the length of the axon and consequently,the impulse is conducted.
$IV.$ Immediately ahead,the axon (e.g.,site $B$) membrane has a positive charge on the outer surface and a negative charge on its inner surface. As a result,a current flows on the inner surface from site $A$ to site $B$.

The potential difference between the outside and inside of a nerve fiber before excitation is known as: