Question

Which of the following describes passive transport?

A) It does not require a concentration gradient.
B) It can only be used to move materials up a concentration gradient.
C) It does not require an expenditure of energy by the cell itself.
D) It requires energy from ATP.

Answer 1

Passive transport is the movement of substances across a cell membrane without using cellular energy and relies on diffusion from higher to lower concentration areas.

Step-by-step explanation:

Passive transport describes the movement of substances across a cell membrane without the expenditure of energy by the cell.

Unlike active transport, which requires energy in the form of ATP to move substances against a concentration gradient, passive transport relies on the natural motion of particles from an area of higher concentration to an area of lower concentration, a process known as diffusion.

Therefore, the best description of passive transport among the provided options is that it does not require an expenditure of energy by the cell itself.