If O2 is found in high concentration on the outside of the cell: a) energy will be expended to pump it inside the cell. b) it will move inside the cell through a protein channel. c) it will form a shell around the outside of the cell. d) it will passively diffuse out of the cell. e) none of the above. Solution b.it will move inside the cell through a protein channel. Oxygen enters cells by passing through the cell membrane in a process called diffusion, which is a transport process that does not require energy.Diffusion is the process in which a substance moves from an area of high concentration (the environment outside cells) to an area of low concentration (inside cells) through a semi-permeable mebrane.The cell is constantly using up oxygen in different processes within the cell.As a result,the concentration of oxygen is lower inside the cell than outside.Oxygen diffuses into the cell rather than out of it..