DNA is a nucleic acid polymer composed of which repeating structural unit? a. nucleotides b. phosphate groups c. ribosomes d. proteins

DNA is composed of building blocks called nucleotides. In the structure of DNA, nucleotides are composed of codons which are made up of nitrogen bases: adenine, guanine, uracil and thymine. In this case, adenine and guanine are paired while uracil and thymine are on the other hand paired. The different combinations pertain to different DNA make-up