Bacteria and yeast need to prevent leakage of numerous small molecules through their cell membrane. Biochemists have studied how the composition of the membrane affects passive diffusion and the ...

Charged molecules, however, do not readily diffuse across a lipid bilayer membrane and they require additional assistance. In facilitated transport, membrane proteins assist the diffusion of ...

The permeability of biological membranes is a key determinant of drug pharmacokinetics. Historically, passive diffusion through the lipid bilayer portion of a biological membrane was suggested as ...

Learn how molecules move through membranes by passive diffusion, active transport and osmosis. BBC Bitesize Scotland SQA National 5 Biology revision.

However, does understanding a cell membrane's basic characteristics allow for consensus on how molecules actually pass in and out of these thin yet strong membranes? It is widely assumed that the ...

Learn how molecules move through membranes by passive diffusion, active transport and osmosis. BBC Bitesize Scotland SQA National 5 Biology revision.

Bacteria, fungi, and yeast are very good at excreting useful substances such as weak acids. One way in which they do this is through passive diffusion of molecules across the cell membrane. At the ...