Paul Andersen describes the four major biological molecules found in living things. He begins with a brief discussion of polymerization. Dehydration synthesis is used to connect monomers into polymers and hydrolysis breaks them down again. The major characteristics of nucleic acids are described as well as there directionality from 3' to 5' end. Protein structure is describes as well as the structure of its monomers; amino acids. The carboxyl and amino ends of a protein are described. The major groups of lipids are included with a brief discussion of saturated, unsaturated and trans fats. Finally carbohydrates and their sugar monomers are discussed.