This document summarizes the biosynthesis and degradation of porphyrin and heme. It discusses how glycine and succinyl CoA are condensed to form δ-aminolevulinate, the starting material for porphyrin synthesis. Four molecules of porphobilinogen then condense to form the porphyrin ring. A series of reactions incorporates iron to form heme. Heme is degraded through heme oxygenase to form biliverdin and bilirubin, which is transported to the liver bound to albumin.