HORTICULTURE

Detailed explanation-1: -During active transport, substances move against the concentration gradient, from an area of low concentration to an area of high concentration. This process is “active” because it requires the use of energy (usually in the form of ATP).

Detailed explanation-2: -Diffusion is a random movement of molecules down the pathway called the concentration gradient. Molecules are said to move down the concentration gradient because they move from a region of higher concentration to a region of lower concentration.

Detailed explanation-3: -In facilitated transport, also called facilitated diffusion, material moves across the plasma membrane with the assistance of transmembrane proteins down a concentration gradient (from high to low concentration) without the expenditure of cellular energy.