AP BIOLOGY

Detailed explanation-1: -Diffusion is the movement of molecules from an area of high concentration of the molecules to an area with a lower concentration. For cell transport, diffusion is the movement of small molecules across the cell membrane.

Detailed explanation-2: -In passive transport, substances move from an area of higher concentration to an area of lower concentration in a process called diffusion. A physical space in which there is a different concentration of a single substance is said to have a concentration gradient.

Detailed explanation-3: -Simple diffusion refers to the movement of molecules from an area of higher concentration to an area of lower concentration. In the case of cells, molecules like gases can diffuse directly across the cell’s phospholipid bilayer.