All membranes are porous to some limited extent so that over time low volumes of leachate will cross the membrane.
Water can only pass through the endodermis by crossing the membrane of endodermal cells twice (once to enter and a second time to exit).
At some point they cross the basilar membrane into the fluid below and travel back to a point just beneath the oval window.
In the treatment with the host plant, the fungi crossed the membrane and always emerged within 800 m of the root.
This C-terminal tail contains an acidic region that is thought to aid in crossing the nuclear membrane.
Relatively few ions need to cross the membrane for the membrane voltage to change drastically.
It is an intrinsic membrane protein and is predicted to cross the membrane several times.
All previous models agreed that the first six putative membrane-spanning regions cross the membrane.
There is such a current associated with every type of ion that can cross the membrane.
Permeability: is simply a measure of how easily an ion can cross the membrane.