AP BIOLOGY

Detailed explanation-1: -In passive transport, substances simply move from an area of higher concentration to an area of lower concentration, which does not require the input of energy. Concentration gradient, size of the particles that are diffusing, and temperature of the system affect the rate of diffusion.

Detailed explanation-2: -Diffusion. Diffusion is a passive process of transport. A single substance tends to move from an area of high concentration to an area of low concentration until the concentration is equal across the space.

Detailed explanation-3: -Passive transport is defined as a type of transport that moves substances from an area of greater concentration to an area of lesser concentration. Thus, the movement of substances is along a concentration gradient.

Detailed explanation-4: -If movement is with the concentration or gradient, it is passive. If movement is against the gradient, it is active and requires energy.