When a substance moves from an area of low concentration to an area of high concentration while using energy, the process is termed
A) diffusion.
B) osmosis.
C) facilitated diffusion.
D) pinocytosis.
E) active transport.

Question

Quizplus · Accepted Answer

Active transport is the only process that involves movement of a substance from an area of low concentration to an area of high concentration with the use of energy. Diffusion and osmosis both involve movement of substances from areas of high to low concentration without energy expenditure. Facilitated diffusion also moves substances from high to low concentration, but it does so with the help of specific transport proteins and does not require energy. Pinocytosis is a process by which cells engulf fluids or small particles, and is not directly related to the movement of substances across a concentration gradient.

When a Substance Moves from an Area of Low Concentration