Which are the three parts of a nucleotide?

Which are the three parts of a nucleotide?

• A. Phosphate group
• B. 5-carbon sugar
• C. Nitrogen base
• D. Phosphate group, 5-carbon sugar, and nitrogen base

Answer: (D)

A nucleotide is built from three parts: a five-carbon sugar, a phosphate group, and a nitrogenous base. The sugar (deoxyribose in DNA or ribose in RNA) provides the attachment point for the base and for the phosphate group. The nitrogenous base attaches to the sugar and is the part that encodes genetic information through base pairing. The phosphate group links to the sugar and to the next nucleotide, forming the sugar–phosphate backbone of DNA or RNA via phosphodiester bonds. Because a nucleotide must include all three components to exist, the full trio—phosphate group, five-carbon sugar, and nitrogen base—is the correct description. The other options each name only one piece, but a nucleotide isn’t complete without all three parts.

A nucleotide is built from three parts: a five-carbon sugar, a phosphate group, and a nitrogenous base. The sugar (deoxyribose in DNA or ribose in RNA) provides the attachment point for the base and for the phosphate group. The nitrogenous base attaches to the sugar and is the part that encodes genetic information through base pairing. The phosphate group links to the sugar and to the next nucleotide, forming the sugar–phosphate backbone of DNA or RNA via phosphodiester bonds. Because a nucleotide must include all three components to exist, the full trio—phosphate group, five-carbon sugar, and nitrogen base—is the correct description. The other options each name only one piece, but a nucleotide isn’t complete without all three parts.