(a)[4]
Explain how a haemoglobin molecule illustrates the four levels of organisation in protein molecules. You should refer to: primary structure, secondary structure, tertiary structure, and quaternary structure.
(b)[3]
Use the genetic dictionary to compare the similarities and differences between the two haemoglobin variants.
(c(i))[1]
State the function of collagen in arterial walls.
(c(ii))[1]
State one way in which the structure of collagen is different from the structure of haemoglobin.