This video discusses the structure and function of the cell membrane. The membrane is made up of a double layer of lipids with proteins intercalated between them. The lipids are antipatic, meaning they have a polar hydrophilic head and two nonpolar hydrofobic chains. The proteins can be classified as periferal or extra-cellular, and they attach temporarily to the membrane layer either through water-phase or lipid-phase interactions. Active and passive transport across membranes are also covered, as well as the cell's role in signal transduction. Finally, the cell's identity is conferred via antigenic recognition.