molecule that contains a basic functional group]
Amino acid. Amino acid, any of a group of organic molecules that consist of a basic amino group (âNH2), an acidic carboxyl group (âCOOH), and an organic R group (or side chain) that is unique to each amino acid. The term amino acid is short for Î±-amino [alpha-amino] carboxylic acid. Each molecule contains a central carbon (C) atom, called the Î±-carbon, to which both an amino and a carboxyl group are attached. The remaining two bonds of the Î±-carbon atom are generally satisfied by a hydrogen (H) atom and the R group.