Unique Structure of DNA
DNA is a polymer. The monomer units of DNA are nucleotides, and the polymer is known as a "polynucleotide." Each nucleotide consists of a 5-carbon sugar (deoxyribose), a nitrogen containing base attached to the sugar, and a phosphate group. There are four different types of nucleotides found in DNA, differing only in the nitrogenous base. The four nucleotides are given one letter abbreviations as shorthand for the four bases./nA is for adenine G is for guanine C is for cytosine T is for thymine/nReff: http://www.blc.arizona.edu/molecular_graphics/dna_structure/dna_tutorial.html
