May 23, 2017

The "rungs" of the DNA strand are made up of nitrogenous bases.

#### Explanation:

The "rungs" of the DNA strand are made up of nitrogenous bases which include

• $\textcolor{b l u e}{\text{Guanine (G)}}$

• $\textcolor{g r e e n}{\text{Cytosine (C)}}$

• $\textcolor{\pi n k}{\text{Adenine (A),}} \mathmr{and}$

• $\textcolor{\mathmr{and} a n \ge}{\text{Thymine (T)}}$

$\textcolor{w h i t e}{- - - - - - - -} \textcolor{b l u e}{\text{G}}$ pairs with $\textcolor{g r e e n}{\text{C}}$
$\textcolor{w h i t e}{- - - - - - - -} \textcolor{\pi n k}{\text{A}}$ pairs with $\textcolor{\mathmr{and} a n \ge}{\text{T}}$

By pairs I mean forms hydrogen bonds, which are a type of intermolecular force of attraction and one of the strongest of them all.