The "backbone" of a nucleic acid molecule is made of
A) nitrogenous bases.
B) alternating sugar and phosphate groups.
C) purines.
D) pyrimidines.
E) nucleosides.

Question

Quizplus · Accepted Answer

The backbone of nucleic acid molecules, DNA and RNA, is made up of alternating sugar (deoxyribose or ribose) and phosphate groups. This creates a linear chain-like structure with the nitrogenous bases (purines and pyrimidines) attached to the sugar molecules. Nucleosides are made up of a nitrogenous base attached to a sugar molecule, but they do not contribute to the backbone structure.

The "Backbone" of a Nucleic Acid Molecule Is Made of