Which term best describes a molecule that can join to form polymers, serving as a building block?

Which term best describes a molecule that can join to form polymers, serving as a building block?

• A. Protein
• B. Monomer
• C. Carboxyl Group
• D. Hydroxyl Group

Answer: (B)

A monomer is a molecule that can join with others to form polymers. Polymers are long chains built from repeating subunits, and these subunits are the monomers that connect through chemical bonds during polymerization. That makes the term best described as a building block for polymers. Proteins are actually polymers themselves, made from many amino acids. So they’re the result of monomers joining, not the building block unit described by the term in the question. Carboxyl and hydroxyl groups are functional groups—parts of molecules that participate in reactions—but they aren’t building-block molecules themselves. They help drive polymer formation, yet they aren’t the unit that repeatedly links to form a polymer. For example, amino acids serve as monomers for proteins, and glucose monomers form starch.

A monomer is a molecule that can join with others to form polymers. Polymers are long chains built from repeating subunits, and these subunits are the monomers that connect through chemical bonds during polymerization. That makes the term best described as a building block for polymers.

Proteins are actually polymers themselves, made from many amino acids. So they’re the result of monomers joining, not the building block unit described by the term in the question. Carboxyl and hydroxyl groups are functional groups—parts of molecules that participate in reactions—but they aren’t building-block molecules themselves. They help drive polymer formation, yet they aren’t the unit that repeatedly links to form a polymer. For example, amino acids serve as monomers for proteins, and glucose monomers form starch.