The Mediated Transport of a Substance Across a Plasma Membrane

The mediated transport of a substance across a plasma membrane

A) Depends upon the binding of that substance to a specific site on the membrane protein
B) Depends upon movement of proteins from one side of the membrane to the other
C) Always increases in direct proportion to the increasing concentration of the substance on one side of the membrane
D) Both depends upon the binding of that substance to a specific site on the membrane protein and depends upon movement of proteins from one side of the membrane to the other are correct
E) All of the choices are correct