Molecular model of Glycine, the smallest and simplest of all proteinogenic amino acids, with only a single hydrogen forming its R-Group or side chain. Glycine has several important roles within the body. It is essential for the production of many different acids, including nucleic acids, bile acids, creatine phosphate and porphyrins. Atoms are represented as spheres and are colour-coded: carbon black hydrogen (white), nitrogen blue and oxygen (red). Illustration.