Question

what nucleic acid molecules composed of nitrogenous bases, sugar molecules, and phosphate units

Answer 1

DNA and RNA 

DNA has deoxiribose sugar, phosphate group and nitrogen bases of Adenine, Guanine, Cytosine and thymine

RNA has ribose sugar, Phosphate group and nitrogen bases of Uracil, Guanine, Cytosine and Adenine.

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