Question

Which one of these is NOT an example using facilitated diffusion?

A) Aquaporins facilitate the diffusion of water in the kidney tubules of many mammals.

B) A carrier protein moves sucrose across the membrane with the concentration gradient.

C) Using the sodium-potassium pump involves the hydrolysis of ATP and the release of Na+ to the outside of the cell.

D) Ca+2 moves from high cytoplasmic concentration to low concentration inside the cell using a membrane-spanning protein.

Answer 1

The correct answer is C) using the sodium potassium pump involves the hydrolysis of ATP and the release of Na+ to the outside of the cell.

Step-by-step explanation:

The movement of Na+ and K+ ions across the plasma membrane by the hydrolysis of ATP is an example of active transport because Na+ and K+ ions are transported in the uphill direction against their concentration gradient.

But in facilitated diffusion molecules are transported along their concentration gradient by the help of carrier protein or channel protein without requirement of addition energy from outside.