Diffusion

Diffusion: the gradual movement of particles from a high concentration to a low concentration, natuarally spreading out 

Diffusion is the net movement of particles from an area of a high concentration to a low concentration 

happens in both liquids and gases because particles are free to move around 

cell membranes hold the cell together but also let substances move in and out of the cell, ,meaning it is a partially permeable membrane 

only…