proteins

• polymers of amino acids
• dipeptide is formed from two amino acids
• polypeptide is formed from more than two amino acids
• proteins are made up of one or more polypeptide
• general structure of amino acids - carboxyl group (COOH), amine group (NH2), and an R group, variable side group
• polypeptides are formed by condensation reactions
• amino acids are joined by peptide bonds which are formed by condensation reactions
• biuret test - add a few drops of sodium hydroxide solution to sample. add copper sulphate solution. positive test will be purple