Which part of the enzyme allows substrate specificity?

• A. Allosteric site
• B. Active site
• C. N-terminal domain
• D. Cofactor binding site

Answer: (B)

Verified step by step guidance

1. Understand the concept of substrate specificity: Substrate specificity refers to the ability of an enzyme to recognize and bind to a specific substrate, enabling the enzyme to catalyze a specific reaction.
2. Learn about the active site: The active site is the region of the enzyme where the substrate binds and the chemical reaction occurs. It has a specific shape and chemical properties that match the substrate, ensuring specificity.
3. Differentiate the active site from other parts of the enzyme: The allosteric site is a regulatory site that can bind molecules to modulate enzyme activity, but it does not directly interact with the substrate. Similarly, the N-terminal domain and cofactor binding site are not involved in substrate specificity.
4. Relate enzyme structure to function: The active site is typically formed by amino acid residues that create a unique environment for the substrate, including specific binding interactions such as hydrogen bonds, ionic bonds, and hydrophobic interactions.
5. Conclude that the active site is responsible for substrate specificity: Based on the structural and functional properties of enzymes, the active site is the part of the enzyme that allows it to recognize and bind to a specific substrate.