Molecular Weight & Diffusion (quick question)

[Baron0805]

Sodium does not pass through easily.  There is not way ions can cross a
membrane due to the hydrophobic interior of the membrane.  I don't care how
small they are.  Like disolves like.  The only way that ions can cross are
through ion channels, pores, gap junctions (anything that forms a hydrophilic
channel) or carrier proteins (Ex. sodium potassium ATPase or calcium ATPase).


Question everything!!!!