Final answer:
Intermolecular side chain interactions maintain the tertiary protein structure, which is the three-dimensional folding pattern of a protein.
Step-by-step explanation:
The intermolecular side chain interactions maintain the tertiary protein structure. Tertiary structure refers to the three-dimensional folding pattern of a protein, and it is determined by interactions between amino acid residues that are far apart in the chain. These interactions include disulfide bridges, hydrogen bonds, ionic bonds, and hydrophobic interactions between nonpolar side chains.