The movement of substances from lower to higher concentration across a semipermeable membrane via a specific protein carrier and cell expenditure of energy is called ______.

Question

Quizplus · Accepted Answer

Active transport involves movement of molecules or ions against their concentration gradient, which requires energy input from the cell. It occurs through specific protein carriers in the membrane. Osmosis is the movement of water molecules from higher to lower concentration across a semipermeable membrane, while diffusion is the movement of molecules from higher to lower concentration without the need for a protein carrier or energy expenditure. Endocytosis involves engulfment of substances by the cell membrane and facilitated diffusion involves movement of molecules across a membrane with the help of protein channels, but does not require energy.

The Movement of Substances from Lower to Higher Concentration Across