NEET2004ZoologyNeural Control and CoordinationActual
In the resting state of the neural membrane, diffusion due to concentration gradients, if allowed, would drive:
Options
- AK ⁺ into the cell
- BK ⁺ and Na ⁺ out of the cell
- CNa ⁺ into the cell
- DNa ⁺ out of the cell.
Correct answer
C. Na ⁺ into the cell
Step-by-step solution
In the resting nerve fibre, the cytoplasm inside the axon has a high concentration of K ⁺ and a low concentration of Na ⁺ in contrast to the fluid outside the axon. Thus, if diffusion occurs the through concentration gradient Na ⁺ enters the fibre. Related Theory The sodium-potassium pump is a mechanism of active transport that moves sodium ions out of cells and potassium ions into cells. The sodium-potassium pump moves both ions from areas of lower to higher concentration, using energy in ATP and carrier proteins