Which of the Following Statements Regarding the Movement of Molecules

Multiple Choice

Which of the following statements regarding the movement of molecules across cell membranes is correct?

A) The diffusion of molecules across a cell membrane occurs at a rate that is influenced by the surface area of the membrane and the magnitude of the concentration difference across it
B) The net flux of molecules that cross cell membranes by diffusion is always from regions of lower concentration to regions of higher concentration
C) Molecules that enter a cell by diffusion must directly permeate the lipid portion of the plasma membrane, whereas those that enter by facilitated diffusion utilize membrane-bound proteins
D) Both the diffusion of molecules across a cell membrane occurs at a rate that is influenced by the surface area of the membrane and the magnitude of the concentration difference across it and the net flux of molecules that cross cell membranes by diffusion is always from regions of lower concentration to regions of higher concentration are correct
E) Both the diffusion of molecules across a cell membrane occurs at a rate that is influenced by the surface area of the membrane and the magnitude of the concentration difference across it and molecules that enter a cell by diffusion must directly permeate the lipid portion of the plasma membrane, whereas those that enter by facilitated diffusion utilize membrane-bound proteins are correct