Biochemistry fundamentals — composition of enzymes From a biochemical standpoint, all classical enzymes are composed of which macromolecule class as their primary structural material?

Introduction / Context:
Enzymes are biological catalysts that accelerate reactions under mild conditions with high specificity. Knowing their chemical nature helps in understanding denaturation, pH effects, and active-site chemistry.

Given Data / Assumptions:

• Classical enzymes in cells are macromolecular catalysts built from polypeptide chains.
• Coenzymes or cofactors (metal ions, vitamins) may assist but are not the primary macromolecule.

Concept / Approach:
Proteins are polymers of amino acids. The three-dimensional structure (primary to quaternary) dictates catalytic function. While “amino acids” are the building blocks, the enzyme itself is a protein macromolecule, not free amino acids. Exceptions like ribozymes exist (RNA catalysts), but in standard curricula, enzymes are proteins.

Step-by-Step Solution:
Identify enzyme macromolecule → protein.Distinguish from building blocks (amino acids) and from other biomolecules (lipids, carbohydrates).Therefore, the correct choice is “Proteins.”

Verification / Alternative check:
Textbooks define enzymes as protein catalysts, with ribozymes taught as special RNA-based catalysts.

Why Other Options Are Wrong:

• Fats: function in membranes/energy storage, not catalytic proteins.
• Carbohydrates: structural/energy roles; not the enzyme scaffold.
• Amino acids: monomers, not the assembled macromolecule.

Common Pitfalls:

• Citing “amino acids” because they are components; the question asks about the macromolecule class.

Final Answer:
Proteins