The cell membrane is described as highly selective, because it bars the passage of most but not all substances. what structural feature of the membrane acts like gates that allow certain substances, including water, to pass through the membrane?

a. permanent gaps in the lipid bilayer
b. proteins that temporarily dissolve regions of the lipid bilayer
c. channels in transmembrane proteins embedded in the lipid bilayer
d. channels in phosphate groups at the outer edges of the lipid bilayer



Answer :