In proteins, what is the monomeric subunit that polymerizes to form a polypeptide chain?

• A. Monosaccharide
• B. Amino acid
• C. Fatty acid
• D. Nucleotide

Answer: (B)

Verified step by step guidance

1. Understand that proteins are polymers made up of repeating units called monomers.
2. Recall that the monomeric subunits of proteins are amino acids, which link together through peptide bonds.
3. Recognize that monosaccharides are the monomers of carbohydrates, not proteins.
4. Know that fatty acids are components of lipids, not protein monomers.
5. Identify nucleotides as the monomers of nucleic acids like DNA and RNA, not proteins.