Molecular Basis of Inheritance — BIOLOGY STD 12 Science — Question

1. Adenosine

Explanation:

A nucleoside has a nitrogenous base and a 5-carbon sugar joined via a $\beta$-glycosidic linkage. nucleoside of DNA has deoxyribose sugar wheras that of RNA has ribose sugar. On the basis of different bases, there are five types of nucleoside; cytidine, uridine, adenosine, guanosine, thymidine. When a phosphate group is covalently linked at the 5' hydroxyl of adenosine, it is called as adenylic acid which is a nucelotide. Adenine is a purine base, found in both DNA and RNA, base pairs with thymine via two hydrogen bonds. Deoxyribose is a pentose sugar present in DNA.