Which term best describes the building blocks of proteins?

• A. Nucleotides
• B. Amino acids
• C. Monosaccharides
• D. Fatty acids

Answer: (B)

Proteins are built from amino acids linked together by peptide bonds into long chains that fold into specific shapes to perform their functions. Each amino acid has an amino group, a carboxyl group, a hydrogen, and a unique side chain (R group) that influences its chemical properties and how the chain folds. The sequence and properties of these side chains determine the protein’s structure and activity.

Nucleotides form nucleic acids like DNA and RNA; monosaccharides are the simple sugars that build carbohydrates; fatty acids are components of lipids. That’s why amino acids are the correct building blocks of proteins.