At resting stage nerve cell has

Options

A. Low `K^(+)` outside and high `Na^(+)` inside
B. High `K^(+)` inside and high `Na^(+)` outside
C. High `K^(+)` inside and low `Na^(+)` outside
D. High `K^(+)` outside and low `Na^(+)` inside

Answer

B

Explanation

When a neuron is not conducting any impulse, i.e. resting, the axonal membrane is comparatively more permeable to potassium ions `(K^(+))` and nearly impermeable to sodium ions (`Na^(+)`). Similarly, the membrane is impermeable to negatively charged proteins present in the axoplasm.
Consequently, the axoplam inside the axon contains high concentration of `K^(+)` and negatively charged proteins and low concentration of `Na^(+)`.
In contrast, the fluid outside the axon contains a low concentration of `K^(+)`, a high concentration of `Na^(+)` and thus form a concentration gradient.