Which of the following options illustrates the distribution of `Na^+ and K^+` ions in a section of non-myelinated axon which is at resting potentail ?

Options

A.
B.
C.
D.

Answer

A

Explanation

When a neuron is at resting potential, i.e., not conducting any impulse, the axonal membrane is comparatively more permeable to `K^+` ions and nearly impermeable to `Na^+` ions.Consequently, the axoplasm inside the axon contains high concentration of `K^+` ions.In contrast, the fluid outside the axon has a high concentration of `Na^+` ions and thus, forms a concentration gradient.