Question

Adenosine is an example of :

• A. nucleotide
• B. purine base
• C. pyrimidine base
• D. nucleoside

Answer 1

Answer: (D)

nucleoside

Nucleosides are glycosylamines that can be thought of as nucleotides without a phosphate group. A nucleoside consists simply of a nucleobase (also termed a nitrogenous base) and a five-carbon sugar (either ribose or deoxyribose), whereas a nucleotide is composed of a nucleobase, a five-carbon sugar, and one or more phosphate groups. In a nucleoside, the anomeric carbon is linked through a glycosidic bond to the N${}_9$ of a purine or the N${}_1$ of a pyrimidine. Examples of nucleosides include cytidine, uridine, adenosine, guanosine, thymidine and inosine.

Hence, the correct option is$D$