Beyond the ladder-like structure described above, another key characteristic of double-stranded DNA is its unique three-dimensional shape. The first photographic evidence of this shape was ...

DNA is negatively charged, due to the phosphate groups in its phosphate-sugar backbone, so histones bind ... irregular and not quite the uniform structure depicted in instructive drawings such ...

This diagram depicts the chemical structure of pyrimidine, a six-membered aromatic ring with two nitrogen atoms at positions 1 and 3 (highlighted in blue). The remaining positions are occupied by ...