A process or organisms that does not require oxygen

Anaerobic

Explanation:

Anaerobic is a term that refers to the absence of oxygen during a process (biological or chemical) OR in an living organism. For instance: living organisms that break down complex substances in the absence of oxygen are called Anaerobes, and undergo a anaerobic respiration.

the sugar-phosphate backbone forms the structural framework of nucleic acids, including dna and rna. this backbone is composed of alternating sugar and phosphate groups, and defines directionality of the molecule.