Question

which phrase best defines diffusion? movement of water particles from an area of low concentration to an area of high concentration movement through a cell membrane using energy from atp movement of particles up a concentration gradient with the help of proteins movement of particles from an area of high concentration to an area of low concentration

Explanation:

Diffusion is the passive movement of particles from an area of high concentration to an area of low concentration down a concentration gradient without the use of energy (ATP) and not necessarily through a cell - membrane or with the help of proteins. Movement of water particles from low to high concentration is the opposite of the normal diffusion process and is osmosis when it comes to water. Movement through a cell membrane using energy from ATP is active transport. Movement of particles up a concentration gradient with the help of proteins is also active transport.

Answer:

movement of particles from an area of high concentration to an area of low concentration