What is the difference between osomosis and diffusion? a.) osomosis moves molecules, such as water, through a semipermanent membrane, diffusion moves molecules, such as oxygen and carbon dioxide, through a permeable membrane. b.) osomosis allows all molecules to move from areas of higher concentration to areas of lower concentration, division allows only water molecules the move from areas of higher concentration to areas of lower concentration. c.)osomosis requires facilitation by a channal protein, defusion requires additional energy from and energy carrying molecule like atp. d.)osomosis i’ll cruise over an area called a concentration gradient, diffusion occurs over a membrane bilayer.