Changes

==Final moment of great insight==

==Final moment of great insight==

Watson and Crick worked in a office aggregating and integrating all the known knowledge that they could about what was then known about DNA chemistry. Watson had his great [[insight]] at their Cavendish office on February 28, 1953. He had constructed the flat cardboard models of the four base pairs. The [[base pair]]s consisted of purines adenine and guanine and the pyrimidines thymine and cytosine. He began trying different orientations of them, flipping them over and sliding them around on the office table. He saw a potential for hydrogen bonding between the adenine and thymine. He then oriented the guanine and cytosine in a similar way and saw the same hydrogen bonding pattern. He then compared the two aggregates and saw that they were similar in shape and he soon realized that they would be appropriate as perhaps rungs on a ladder and quickly became confident that he had made the final breakthrough.<ref>https://www.dnalc.org/view/15492-Discovering-the-double-helix-structure-of-DNA-James-Watson-video-with-3D-animation-and-narration.html</ref>

Watson and Crick worked in a office aggregating and integrating all the known knowledge that they could about what was then known about DNA chemistry. They worked with molecular models rather than doing research in a laboratory. Watson had his great [[insight]] at their Cavendish office on February 28, 1953. He had constructed the flat cardboard models of the four base pairs. The [[base pair]]s consisted of purines adenine and guanine and the pyrimidines thymine and cytosine. He began trying different orientations of them, flipping them over and sliding them around on the office table. He saw a potential for hydrogen bonding between the adenine and thymine. He then oriented the guanine and cytosine in a similar way and saw the same hydrogen bonding pattern. He then compared the two aggregates and saw that they were similar in shape and he soon realized that they would be appropriate as perhaps rungs on a ladder and quickly became confident that he had made the final breakthrough.<ref>https://www.dnalc.org/view/15492-Discovering-the-double-helix-structure-of-DNA-James-Watson-video-with-3D-animation-and-narration.html</ref>

==Notes==

==Notes==