Substances are absorbed and retained against a concentration gradient, through the expenditure of energy, by _____________________.

Question

Quizplus · Accepted Answer

Active transport is the process by which substances are absorbed and retained against a concentration gradient, using energy to drive the movement of substances across a membrane. The other options do not involve the movement of substances against a concentration gradient or the expenditure of energy.

Substances Are Absorbed and Retained Against a Concentration Gradient, Through