DNA is the nucleic acid that forms the genetic material in all organisms. The structure of deoxyribose nucleic acid was elucidated by Watson and Crick. The DNA is a double helical structure having two anti-parallel strands of polynucleotide chains joined to each other by hydrogen bonding [B] formed between the N-bases. The backbone of the structure is constituted by the sugar-phosphate linked by the phosphodiester bond[C]. N-bases from double and triple H-bonds where Adenine always binds to Thymine (2 bonds) and Guanine binds to Cytosine (3 bonds). The N-bases are joined to the sugar structure by forming N-glycosidic bond[A] .