Which $C$ atom of ribose sugar (numbered from $1^{\prime}$ to $5^{\prime}$) bonds with the phosphate group to form $AMP$ (in $^{\prime}$)?

The double-helical structure of $DNA$ is due to ....

For a double strand $DNA$,one strand is given below:
$5'-A-G-T-C-A-C-G-T-A-A-G-T-C-3'$
The amount of energy required to split the double strand $DNA$ into two single strands is $.... \ kcal \ mol^{-1}$.
[Given: Average energy per $H$-bond for $A-T$ base pair $= 1.0 \ kcal \ mol^{-1}$,$G-C$ base pair $= 1.5 \ kcal \ mol^{-1}$. Ignore electrostatic repulsion between the phosphate groups.]

Identify the linkage in backbone of single strand of DNA?

$RNA$ is different from $DNA$ because it contains ...

Which substance is not present in nucleic acid?