Question

which statement best describes how active transport differs from passive transport? a. only active transport requires atp. b. only active transport moves small particles. c. only active transport relies on a plasma membrane. d. only active transport allows substances to leave a cell.

Explanation:

To solve this, we analyze each option:

• Option A: Active transport needs ATP (energy) to move substances against concentration gradient. Passive transport (like diffusion, osmosis) doesn’t require ATP. This matches the key difference.
• Option B: Both active and passive transport move small particles (e.g., ions, small molecules). Eliminate B.
• Option C: Both rely on the plasma membrane (as transport occurs across it). Eliminate C.
• Option D: Both allow substances to leave a cell (e.g., passive: CO₂ diffusion out; active: some ions pumped out). Eliminate D.

Answer:

A. Only active transport requires ATP.