Question

What makes up the backbone of DNA


Sugar-nitrogen base


sugar-phosphate


phosphate-nitrogen base

Answer 1

The backbone of DNA is made up of **sugar-phosphate**. Specifically, the backbone consists of alternating sugar (deoxyribose) and phosphate groups, which are connected by covalent bonds. The nitrogenous bases (adenine, thymine, cytosine, and guanine) attach to the sugar molecules and project inward, forming base pairs.