Nucleic acids exhibit secondary structure. Describe through the Watson-Crick model.

(N/A) The Watson-Crick model of $DNA$ describes its secondary structure as a double helix.
Key features of the model include:
$1$. $DNA$ consists of two polynucleotide chains that run in an anti-parallel direction, meaning one chain runs in the $5' \rightarrow 3'$ direction and the other in the $3' \rightarrow 5'$ direction.
$2$. The backbone is formed by sugar-phosphate linkages. $A$ phosphate moiety links the $3'$-carbon of one sugar to the $5'$-carbon of the sugar of the succeeding nucleotide via phosphodiester bonds.
$3$. The two chains are held together by hydrogen bonds between nitrogenous bases. Adenine $(A)$ pairs with Thymine $(T)$ via two hydrogen bonds, and Guanine $(G)$ pairs with Cytosine $(C)$ via three hydrogen bonds.
$4$. The helix is right-handed. One full turn of the helical strand involves $10$ base pairs.
$5$. The pitch of the helix is $3.4 \text{ nm}$ $(34 \text{ Å})$, and the distance between two successive base pairs is $0.34 \text{ nm}$ $(3.4 \text{ Å})$.
$6$. This specific form of $DNA$ is known as $B-DNA$.