Certain tumor cells are known to have a plasma membrane Na⁺ channel that is activated by acidic extracellular pH. In these cells, if acid is added to the extracellular medium, the: A) Membrane potential will hyperpolarize. B) Rate of ATP utilization will increase. C) Cells will shrink. D) Na⁺ K⁺-ATPase will become inactivated. E) K⁺ efflux will decrease.

Question

Quizplus · Accepted Answer

The activation of Na⁺ channels by acidic pH will lead to increased Na⁺ influx, which will require more ATP to be used by the Na⁺ K⁺-ATPase to pump Na⁺ out of the cell, thus increasing the rate of ATP utilization.

Certain Tumor Cells Are Known to Have a Plasma Membrane