Na+/K+-ATPase pump uses what type of transport?

• A. Passive diffusion
• B. Facilitated diffusion
• C. Active transport
• D. Endocytosis

Answer: (C)

The main concept is that this pump uses energy from ATP to move ions against their gradients, which is active transport. It hydrolyzes ATP to drive conformational changes that push three Na+ out of the cell and two K+ in, maintaining the membrane potential. This energy-dependent movement distinguishes it from passive diffusion (which occurs down a gradient without energy) and facilitated diffusion (which uses a protein but still travels with the gradient). Endocytosis involves engulfing material into vesicles, not pumping ions across the membrane.