compare dna to a ladder the backbone is made of the rungs are made of

compare dna to a ladder the backbone is made of
the rungs are made of

Brief Explanations

The DNA backbone is composed of sugar - phosphate groups. The rungs are made of nitrogenous base pairs (adenine - thymine, cytosine - guanine).

Backbone: Sugar - phosphate groups; Rungs: Nitrogenous base pairs