How do substances like CO2 and water move in and out of the cell? Discuss.

Substances move in and out of the cell by diffusion. Diffusion is the spontaneous movement of particles in order to attain equilibrium in concentration. While the movement of water through a semi-permeable membrane is called osmosis. It is important to note that plasma membrane is a semi-permeable membrane. Water always moves from high water concentration to low water concentration.