3 configurations of the secondary structure of a protein. 1. Random Walk –stretched out 2. Beta Pleated Sheet-spider web, nails 3. Alpha Helix-cylindrical spiral can be stretched (hair) As a polypeptide chain, the molecule had no special properties, but as a 3 dimensional protein, the molecule is capable of performing an astonishing variety of feats. Globular proteins catalyze chemical reactions, others act as antibodies in the immune system, & violent bodily reactions in the blood system.