Question

During the transmission of nerve imuplse, which of the following takes place?

• A. Flux of Na${}^{+}$ inwards and K${}^{+}$ outwards
• B. Flux of K${}^{+}$ inwards and Na${}^{+}$ outwards
• C. Flux of K${}^{+}$ inwards and Na${}^{+}$ inwards
• D. Flux of K${}^{+}$ outwards and Na${}^{+}$ outwards

Answer 1

The correct option is A Flux of Na${}^{+}$ inwards and K${}^{+}$ outwards

Nerve impulses are initiated by incoming chemical stimuli or excitatory signals, which decrease the membrane potential and depolarize the membrane. With depolarization of the membrane, there is an increase in its permeability to sodium ions. The positively charged sodium ions rush inwards into the interior of the cell, while potassium ions rush outwards to the exterior of the cell. This spike of electrical activity is called as the action potential and generates the nerve impulse. So, the correct answer is option A.