What is the term referring to how proteins on cell membranes control what goes through them? I know it's selective something... it's just at the tip of my tongue but this is where I need your help!

Question

anonymous · Answer

Not what goes through them but how they push molecules across a membrane against a concentration graident

anonymous · Answer

True I worded it wrong, but the specific term regarding this event is what I'm looking for.

anonymous · Answer

Never mind, I found it: selective permeability. But thanks!