Question

Which of the following statements about ATP-powered pumps is NOT true? All ATP-powered pumps contain at least one transmembrane domain. F-class and V-class pumps transport the same ion but in opposite directions. Only P-, F-, and V-class pumps transport ions. ABC transporters are found in organisms ranging from bacteria to humans.

Answer 1

Answer:

Only P-, F-, and V-class pumps transport ions.

Explanation:

The distinct classes of ATPases include:

1) Only the P-type ATPase actively transports ions across biological membranes. P-ATPases (also named E1-E2 ATPases) are found both in plasma and organelle membranes. These ATPases serve to transport ions and phospholipids by hydrolyzing ATP to ADP and phosphate.

2) A- and F-ATPases synthesize ATP by transforming the energy from a gradient of ions across the cell membrane.

3) V-ATPase (also known as Vacuolar-H+ ATPases) acidifies vacuole, lysosome, endosome and Golgi membranes. This type of ATPase couples the hydrolysis of ATP to the active transport of protons across biological membranes.

4) E-ATPases hydrolyze extracellular ATP.