Cell membrane segment with channels and glycoproteins

Elementary cell membrane is composed of phospolipid molecules that form a bilayer that is in its care water repellent (hydrophobic) and on its periphery water friendly (hydrophilic). Through the membrane protrude membrane proteins like the membrane channels. They are hydrophobic in their middle part and hydrophillic on the periphery, where they face on one side the cell exterior and on the other side the cell interior.