Which statement best describes nucleic acids?

Which statement best describes nucleic acids?

• A. Polymers of nucleotides.
• B. Monomers of nucleotides.
• C. Carbohydrates.
• D. Proteins.

Answer: (A)

Nucleic acids are polymers built from nucleotide units. Each nucleotide, comprising a sugar, a phosphate group, and a nitrogenous base, links to the next one through phosphodiester bonds to form a long sugar–phosphate backbone with bases sticking out. This polymeric structure is what stores, copies, and transmits genetic information in organisms. Saying nucleic acids are monomers of nucleotides would invert the relationship—the monomers are the nucleotides, while the polymer is the nucleic acid. Carbohydrates and proteins are different biomolecule classes, so they don’t describe the nature of nucleic acids.

Nucleic acids are polymers built from nucleotide units. Each nucleotide, comprising a sugar, a phosphate group, and a nitrogenous base, links to the next one through phosphodiester bonds to form a long sugar–phosphate backbone with bases sticking out. This polymeric structure is what stores, copies, and transmits genetic information in organisms. Saying nucleic acids are monomers of nucleotides would invert the relationship—the monomers are the nucleotides, while the polymer is the nucleic acid. Carbohydrates and proteins are different biomolecule classes, so they don’t describe the nature of nucleic acids.