Answer:
D. both a and b
Step-by-step explanation:
Amino acids are the building blocks of proteins, and their properties are determined by the side chain or "R" group attached to the central carbon atom. When amino acids combine, they form peptide bonds, creating long chains of amino acids that fold into specific three-dimensional structures, such as the globular structure of enzymes.
The active site of an enzyme is the region where the substrate binds and the chemical reaction occurs. This region is typically a small cleft or pocket on the surface of the enzyme, and it is formed by the specific arrangement of amino acid residues that create a unique environment for the substrate to react. The shape and chemical properties of the active site are determined by the globular structure of the enzyme and the charges of the amino acid residues that line the active site.
Therefore, the active site of an amino acid is produced by the combination of the globular structure and charges of the amino acid residues that make up the enzyme.