Facilitated diffusion and active transport both require a transport protein in order to function. However, they also differ in how they transport molecules.

Question

Which one of the following BEST describes the difference in how they move molecules across a cell membrane?

Question 7 options:

Facilitated diffusion moves molecules with their concentration gradient, while active transport moves molecules against their concentration gradient.

Facilitated diffusion moves molecules against their concentration gradient, while active transport moves molecules with their concentration gradient.

Facilitated diffusion moves molecules equally across their concentration gradient, while active transport moves molecules with their concentration gradient.

Facilitated diffusion moves molecules with their concentration gradient, while active transport move molecules equally across their concentration gradient.

Answer 1

The option that BEST describes the difference in how facilitated diffusion and active transport move molecules across a cell membrane is:

Facilitated diffusion moves molecules with their concentration gradient, while active transport moves molecules against their concentration gradient.

This is because facilitated diffusion allows substances to move from an area of higher concentration to an area of lower concentration without the use of energy, while active transport requires energy (usually in the form of ATP) to move substances from an area of lower concentration to an area of higher concentration, which is against their concentration gradient.