During the propagation of a nerve impulse, the action potential results from the movement of

Options

A. `K^(+)` ions from extracellular fluid to intracellular fluid
B. `NA^(+)` ions from intracellular fluid to extracellular fluid
C. `K^(+)` ions from intracellular fluid to extracellular fluid
D. `NA^(+)` ions from extracellular fluid to intracellular fluid

Answer

A

Explanation

During the nerve impulse when a stimulus of adequate strength is applied to a polarised membrane, the permeability of the membrane to `Na^(+)` is increased at the point of stimulation. As a result the sodium ion channels permit the influx of `Na^(+)` by diffusion into the intracellular fluid from extracellular fluid.