DNA structure

• polymer of many nucleotides
• 2 polynucleotide strands
• 2 strands run in opposite directions (antiparallel) - double helix
• a phosphate group, five carbon sugar (deoxyribose) and a nitrogenous base
• the bases are adenine, thymine, cytosine and guanine
• a phosphodiester bond is covalent
• has a sugar-phosphate backbone