What are the difference and similarities between osmosis and diffusion? Biology Movement In and Out of Cells Osmosis 1 Answer Rawda Eada Nov 16, 2015 Both go down concentration gradient. Osmosis is the movement of water molecules, but diffusion is for any molecule. Osmosis happens across a partially permeable membrane, while diffusion does not need a membrane, it happens directly in the fluid. Answer link Related questions How can osmosis be used in real life? How can osmosis affect a cell? Why is osmosis a unique form of diffusion? What are some examples of osmosis? What is osmosis? How do aquaporins facilitate the passage of water? How do jellyfish overcome osmosis? What are the differences between diffusion, osmosis, facilitated diffusion & active transport?... What happens to cells during osmosis? If a celery stick was placed in a beaker of water and another was placed in a beaker of salt... See all questions in Osmosis Impact of this question 7536 views around the world You can reuse this answer Creative Commons License