NEET2008ZoologyNeural Control and CoordinationActual
During the propagation of a nerve impulse, the action potential results from the movement of
Options
- ANa ⁺ ions from extracellular fluid to intracellular fluid
- BKa ⁺ ions from extracellular fluid to intracellular fluid
- CNa ⁺ ions from intracellular fluid to extracellular fluid
- DKa ⁺ ions from intracellular fluid to extracellular fluid
Correct answer
A. Na ⁺ ions from extracellular fluid to intracellular fluid
Step-by-step solution
When the threshold stimulus is applied, the permeability of the membrane for sodium ions will change. Voltage gated sodium ion channels open and Na ⁺ ion flows form extracellular fluid to intracellular fluid, the outside becomes negative and inside positive. The membrane is depolarised & when the two ends of this membrane is connected to oscilloscope a potential difference of +30 mv , called as action potential is generated.