Forms the basic structural unit of nucleic acids such as DNA

Forms the basic structural unit of nucleic acids such as DNA

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

Answer: (A)

The basic unit of nucleic acids is the nucleotide. Each nucleotide contains a five‑carbon sugar (deoxyribose in DNA or ribose in RNA), a phosphate group, and a nitrogenous base. These nucleotides link together through phosphodiester bonds to form the sugar–phosphate backbone of DNA or RNA, with the bases extending outward to encode genetic information. The other molecules listed are building blocks for different biomolecules: amino acids make proteins, monosaccharides build carbohydrates, and fatty acids form lipids. So nucleotides are the specific monomers that compose nucleic acids like DNA.

The basic unit of nucleic acids is the nucleotide. Each nucleotide contains a five‑carbon sugar (deoxyribose in DNA or ribose in RNA), a phosphate group, and a nitrogenous base. These nucleotides link together through phosphodiester bonds to form the sugar–phosphate backbone of DNA or RNA, with the bases extending outward to encode genetic information. The other molecules listed are building blocks for different biomolecules: amino acids make proteins, monosaccharides build carbohydrates, and fatty acids form lipids. So nucleotides are the specific monomers that compose nucleic acids like DNA.