Secondary Structure

The secondary structure of a protein refers to the basic foldings of a protein the forms of:

1. an alpha helix

2. a beta-pleated sheet

These foldings are determined by hydrogen bonds. These hydrogen bond form between the N-H bond and the C=O bonds of adjacent amino acids. 

Tertairy Structure:

The tertiary structure of a protein refers to more extensive foldings of a protein giving it a more unique shape.

These folding are determined by the interations of R groups with other amino acids and its environment.

These interactions include:

o   Disulfide bridges

o   Ionic bonds

o   Hydrophillic anf hydrophobic interactions

o   Extra hydrogen bonds (formed by R groups only)