What is a waste product of photosynthesis that organisms need for cellular respiration

Oxygen

Explanation:

A waste product of photosynthesis organisms need for cellular respiration is oxygen. We breathe out carbon dioxide and plants use carbon dioxide during photosynthesis and in return they give us oxygen which is their waste product.

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.