What membrane molecule is responsible for aiding passage of polar molecules into and out of the cell?

            AS we know that the composition of plasma membrane is solely composed of phospholipids and protein molecules. lipid bilayer made up of phospholipid acts as differential permeable membrane because it allow only the transport of non polar molecules. however, there are some proteins known as carrier proteins that help in the transport of polar molecules through facilitated diffusion.

a

explanation:

"a.) well–developed vascular system."