a) Describe what is meant by the primary, secondary, tertiary and quaternary structure of Collagen, and relate these to the mechanical properties of this structural protein.

b) Describe how the ratio of collagen to apatite influences the strain response and toughness of boney structures using appropriate examples from the animal kingdom.

c) Write brief notes on the biosynthesis and degradation of collagen.

d) With the aid of appropriate diagrams, describe the composition and properties of the protein Elastin.