What makes up a nucleotide?

What makes up a nucleotide?

• A. A ribose sugar with a phosphate group and a nitrogenous base
• B. Only a phosphate group and a sugar
• C. A nitrogenous base and a sugar
• D. Phosphate group linked to a deoxyribose sugar and 1 of 4 nitrogenous bases

Answer: (D)

A nucleotide consists of three parts: a five-carbon sugar, a phosphate group, and a nitrogenous base. In DNA, the sugar is deoxyribose, not ribose, and the base can be one of four options: adenine, thymine, cytosine, or guanine. The phosphate attaches to the sugar, forming the backbone of the strand, while the base provides the genetic code through specific pairings. Therefore, the description that includes a phosphate group linked to a deoxyribose sugar and one of the four nitrogenous bases best captures the full structure of a DNA nucleotide. The other descriptions miss one essential component or specify the wrong sugar.

A nucleotide consists of three parts: a five-carbon sugar, a phosphate group, and a nitrogenous base. In DNA, the sugar is deoxyribose, not ribose, and the base can be one of four options: adenine, thymine, cytosine, or guanine. The phosphate attaches to the sugar, forming the backbone of the strand, while the base provides the genetic code through specific pairings. Therefore, the description that includes a phosphate group linked to a deoxyribose sugar and one of the four nitrogenous bases best captures the full structure of a DNA nucleotide. The other descriptions miss one essential component or specify the wrong sugar.