Phosphodiester linkages: repeating, sugar-phosphate backbone of the polynucleotide chain CH 3 N一HNA CH HO 2 G-H DNN C CH? CH2 CH2 N CH? H… cN…HNG CH2 3 DNA polarity: is defined by the asymmetry of the 5.nucleotides and the way they are joinedDNA polarity: is defined by the asymmetry of the nucleotides and the way they are joined. Phosphodiester linkages: repeating, sugar-phosphate backbone of the polynucleotide chain