Which of the following is a purine derivative?

The number of hydrogen bonds between guanine and cytosine; and between adenine and thymine in $DNA$ is

Identify the carbon atom numbered from $C_1^{\prime}$ to $C_5^{\prime}$ of the monosaccharide unit of a $DNA$ nucleotide that lacks an oxygen atom from the $-OH$ group.

Which statement is correct for the nucleotides of $DNA$?

$RNA$ and $DNA$ are chiral molecules. Their chirality is due to the presence of:

Identify the nucleoside from the following: