Final answer:
The amino acid that exhibits a beta-branched side chain is threonine.
Step-by-step explanation:
Amino acids are the building blocks of proteins, and each amino acid has a unique side chain (R-group) that distinguishes it from others. Threonine is the amino acid that exhibits a beta-branched side chain. The term "beta-branched" refers to the branching of the side chain at the beta-carbon atom, which is the second carbon atom in the side chain.
The structure of threonine includes a methyl group (-CH₃) attached to the beta-carbon, creating a branched side chain. This branched structure contributes to the unique properties of threonine and its role in protein structure and function. The beta-branched side chain affects the spatial arrangement of amino acids in a protein, influencing its overall three-dimensional structure and function.
Understanding the structural features of amino acids, including the nature of their side chains, is fundamental in biochemistry and molecular biology. It provides insights into how proteins fold and interact, impacting their biological functions. In the case of threonine, the beta-branched side chain introduces specific steric and chemical properties that contribute to the diversity of amino acids and the complexity of protein structures.