Write the structures of fragments produced on complete hydrolysis of $DNA$? How are they linked in $DNA$ molecule? Draw the diagram to show pairing of nucleotide bases in double helix of $DNA$?

(N/A) Complete hydrolysis of $DNA$ yields three types of fragments:
$1$. $A$ pentose sugar $(2-deoxy-D-ribose)$.
$2$. Phosphoric acid $(H_3PO_4)$.
$3$. Nitrogenous bases: Adenine $(A)$,Guanine $(G)$,Cytosine $(C)$,and Thymine $(T)$.
In a $DNA$ molecule,these fragments are linked as follows:
- The nitrogenous base is attached to the $C1'$ position of the $2-deoxy-D-ribose$ sugar via a $\beta-N-glycosidic$ linkage to form a nucleoside.
- The phosphoric acid is attached to the $C5'$ position of the sugar via a phosphodiester linkage to form a nucleotide.
- Nucleotides are linked together by $3'-5'$ phosphodiester bonds to form the polynucleotide chain.
Base pairing in the $DNA$ double helix occurs via hydrogen bonds:
- Adenine $(A)$ pairs with Thymine $(T)$ via two hydrogen bonds $(A=T)$.
- Guanine $(G)$ pairs with Cytosine $(C)$ via three hydrogen bonds $(G\equiv C)$.