Which listing correctly identifies the three components of a nucleotide?

Which listing correctly identifies the three components of a nucleotide?

• A. Pentose sugar, nitrogen base, phosphate
• B. Amino acid chain, side chain
• C. Glycerol, fatty acids
• D. Ribose only

Answer: (C)

Nucleotides are the building blocks of nucleic acids, and each one has three parts: a five-carbon sugar (pentose), a nitrogenous base, and a phosphate group. The sugar provides the backbone, the base carries genetic information (A, T/U, C, G), and the phosphate group links nucleotides together to form the sugar-phosphate backbone of DNA or RNA. This is why the listing that includes a pentose sugar, a nitrogen base, and a phosphate is correct. The other options describe different biomolecules or are incomplete: amino acid chains relate to proteins, glycerol and fatty acids relate to lipids, and a sugar alone (ribose only) isn’t enough because a nucleotide also needs a base and a phosphate.

Nucleotides are the building blocks of nucleic acids, and each one has three parts: a five-carbon sugar (pentose), a nitrogenous base, and a phosphate group. The sugar provides the backbone, the base carries genetic information (A, T/U, C, G), and the phosphate group links nucleotides together to form the sugar-phosphate backbone of DNA or RNA. This is why the listing that includes a pentose sugar, a nitrogen base, and a phosphate is correct. The other options describe different biomolecules or are incomplete: amino acid chains relate to proteins, glycerol and fatty acids relate to lipids, and a sugar alone (ribose only) isn’t enough because a nucleotide also needs a base and a phosphate.