Solution to PS 3 #5

The principal component of hair is the protein keratin which is made up of bundles of a-helices. These helices are held together by H-bonds along the axis which gives rise to hair's ability to stretch along the axis (without breaking any covalent bonds). Silk is made up of b-sheet structure which has all the polyeptide in a fully extended formation.  To stretch the structure further along the peptide chains in silk would involve breaking peptide bonds.



Return to Problem Set #3