Proteins

• amino acids are the monomers of all polypeptides
• The primary structure of a polypeptide chain is the specific order of amino acids joined by peptide bonds in condensation reactions
• The secondary structure of a polypeptide chain is the folding of the chain into alpha helices and beta pleated sheets by hydrogen bonding between amine and carboxyl groups
• The tertiary structure of a polypeptide chain consists of hydrogen, ionic and disulphide bonding between R groups
• The tertiary structure is important as it provides a specific shape to the polypeptide chain exposing certain R groups to suit its function
• The quaternary structure of a protein can be globular or fibrous and made of multiple polypeptide chains
• Fibrous proteins are less susceptible to temperature change and are structural proteins
• Globular proteins can denature under extreme temperatures causing a change in shape and loss of function