1.9 — proteins: structures

Question 1

what are the four types of protein structure?

Answer 1

primary, secondary, tertiary and quaternary

Question 2

what is the primary structure of a protein?

Answer 2

the unique sequence of amino acids in the polypeptide chain. it’s held together by peptide bonds. a change with one of the amino acids in the chain can result in a change to the protein’s structure and function.

Question 3

what is the secondary structure of a protein?

Answer 3

involves hydrogen bonds forming between the amino group of one amino acid and the carboxyl group of another milano acid further down the chain. this causes the polypeptide (amino acid) chain to coil into either an alpha-helix or a beta-pleated sheet structure

Question 4

what is the tertiary structure of a protein?

Answer 4

where the polypeptide chain folds and twists further to create a complex 3D structure

Question 5

what bonds are present in the primary structure?

Answer 5

peptide bonds

Question 6

what bonds are present in the secondary structure?

Answer 6

hydrogen bonds

Question 7

what bonds are present in tertiary structure

Answer 7

hydrogen and ionic bonds, disulphide bridges and hydrophobic/hydrophilic interactions

Question 8

what bonds are present in quaternary structure

Answer 8

hydrogen, ionic, disulphide, hydrophobic/hydrophilic