CK-12 Foundation
Ck 12: Facilitated Diffusion
[Free Registration/Login may be required to access all resource tools.] In this activity students will learn about facilitated diffusion and the role of transport proteins, channel proteins, and carrier proteins.
Biology Pages
Kimball's Biology Pages: Transport Across Cell Membranes
This site has information on how facilitated diffusion of ions takes place through proteins, or assemblies of proteins, embedded in the plasma membrane. Includes a helpful diagram.