AP BIOLOGY

Detailed explanation-1: -Diffusion refers to the process by which molecules intermingle as a result of their kinetic energy of random motion. It is the net movement of molecules or atoms from a region of high concentration to a region of low concentration. This is also referred to as the movement of a substance down a concentration gradient.

Detailed explanation-2: -Final answer: Movement of molecules from their higher concentration to their lower concentration is called diffusion.

Detailed explanation-3: -Passive transport is a naturally occurring phenomenon and does not require the cell to expend energy to accomplish the movement. In passive transport, substances move from an area of higher concentration to an area of lower concentration in a process called diffusion.