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The Role of ATP in Maintaining Ionic Homeostasis

APBIO-DHKETQ

If ATP was unavailable to the cell, as would be the case when treated with an uncoupler of oxidative phosphorylation, the effects would be numerous. Among them, $Na^+/K^+$ ATPase function would be inhibited.

What would be a consequence of such an inhibitory action?

A

Inhibiting the $Na^+ / K^+$ pump would cause a cessation of all ion movement.

B

Sodium would leak into the cell, and potassium would leak out of the cell, down their electrochemical gradients.

C

The ion concentration in the cell would "drift" towards that of the intercellular fluid.

D

Water would flow out of the cell, leading to crenation.