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 ...

This way DNA can reproduce itself without changing its structure -- except for occasional errors, or mutations. The structure so perfectly fit the experimental data that it was almost immediately ...

But James Watson and Francis Crick's claim was a valid one, for they had in fact discovered the structure of DNA, the chemical that encodes instructions for building and replicating almost all ...