Plasma Membrane and Transport
In cells where only the Na+/K+ pump and the Na+/glucose pump were functional, and where there were high concentrations of glucose and potassium outside the cell, what would you expect to happen?
|A||There would be a build up of sodium inside the cell.|
|B||There would be a build up of potassium inside the cell.|
|C||There would be an equilibrium of sodium inside and outside of the cell.|
|D||There would be an equilibrium of glucose inside and outside of the cell.|
Under these conditions, sodium transport out of the cell (by the Na+/K+ pump) and its import ( via the Na+/glucose pump) would not be affected, so both of these pumps would be functional, and there would be no build up of sodium inside the cell (choice A). Equilibrium of sodium and/or glucose (choices C and D, respectively) may occur, but this is unlikely as the pumps will continue to work. However, if no other pump is active, there would be a build up of potassium inside the cell.