Amino Acids Structures Tutor is an app to teach you the complete structure of each of the twenty amino acids. For ease of learning, the common structure between each of the twenty amino acids is presented to the left side of the picture in black and each unique side chain is presented to the right with most atoms displayed in different colors to help memorize each element in the side chain and their numbers. You will learn each structure that corresponds to each amino acid name. You will learn which structure and which amino acid full name corresponds to which three letter code for the amino acid. You will learn which structure and which amino acid full name corresponds to which one letter code for the amino acid. You will learn to associate the charge or polarity with each structure, full name, three letter code and one letter code. There is a review section which shows the structure, full name, three letter code and one letter code together as a refresher and memory aid.