________ processes move substances across a membrane regardless of concentration gradients.
A) Active transport
B) Filtration
C) Passive transport
D) Diffusion
E) Osmotic

Question

Quizplus · Accepted Answer

Active transport processes require the use of energy to move substances against their concentration gradients, whereas both filtration and diffusion processes move substances with their concentration gradients. Osmotic processes specifically move water molecules across a membrane in response to concentration gradients, but do not move other substances. Passive transport processes can include diffusion, as well as facilitated diffusion, in which substances are moved across a membrane through protein channels without the use of cellular energy. Therefore, only active transport processes move substances across a membrane regardless of concentration gradients.

________ Processes Move Substances Across a Membrane Regardless of Concentration