Protein molecules are polymers (chains) of __________.

• A. DNA molecules
• B. fatty acid molecules
• C. sucrose molecules
• D. purines and pyrimidines
• E. amino acid molecules

Answer: (E)

Verified step by step guidance

1. Understand that proteins are large, complex molecules that play many critical roles in the body. They are made up of smaller units called amino acids.
2. Recognize that amino acids are organic compounds that combine to form proteins. They are the building blocks of proteins.
3. Recall that DNA molecules are composed of nucleotides, which include purines and pyrimidines, not amino acids.
4. Identify that fatty acids are components of lipids, not proteins.
5. Conclude that proteins are polymers of amino acids, as they are linked together in a chain to form a protein molecule.