LIPIDS & MEMBRANE STRUCTURE Lipids differ from the other macromolecules: not formed by linear polymerization however, they do have a high molecular weight they contribute to important cellular structures (membranes) What are they? Heterogeneous category of cellular components that are insoluble in water (hydrophobic) Lipids are typically rich in nonpolar hydrocarbon regions with relatively few polar groups Lipids have 3 main cellular functions: 1. Energy storage (fat to sugar) Lipids have about 6 times more energy than the same weight of a polysaccharide 2. Membrane structure 3. Transmission of chemical signals There are six main classes of lipids (FAMILIARIZE WITH THE FIRST 3) Fatty acids are the building blocks for several other kinds of lipids