| Title/link | Description |
|---|---|
| The Cell: Passive Transport Osmosis | A Learning Object on Osmosis and how it affects the living cell, hosted at the Wisconsin Online Resource Center. |
| The Cell: Passive Transport Diffusion | Also at the Wisconsin Center, this learning object describes the process of diffusion in liquids and outlines the concept of a concentration gradient. |
| Concentration Gradients (RLO) | An RLO which describes the concept of concentration gradients in biological systems through analogy with gradients found in everyday life, and outlines passive and active transport across cell membranes. |
| Diffusion and Osmosis | A brief but clear tutorial on diffusion and osmosis, including osmotic pressure and membrane transport, from a Physics perspective. |
| BBC Education: Pathways into and out of the Cell | An animated tutorial on the passage of substances through the cell membrane, including the role of diffusion and osmosis. |