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1.2. At the heart of the cell: the DNA macromolecule
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During the last session, we saw how at the heart of the cell there's DNA in the nucleus, sometimes of cells, or directly in the cytoplasm of the bacteria. The DNA is what we call a macromolecule, that is a very long molecule. It's Avery, in 1944, who discovered that the DNA was the support of genetic information. But the scientists who are most well-known for DNA are Francis Crick and James Watson who discovered together, with Maurice Wilkins and Rosalind Franklin, in 1953, the structure of DNA, the famous double helix, the two strands. Here are Crick and Watson explaining on a very crude wire model far away from the kind of modelwe would build nowadays with a computer visualization technic. They're showing the two strands of the DNA. They wrote a three page paper inwhich they had this very famous sentence: "It did not escapeour attention that this double helix structure was a way to explain how a DNA could replicate and then how its cell, one cell could give birth to two cells. " Wilkins was a scientist associated with this research in doing all the experimentally say to getthe structure of the molecule, to give clues on the structure of the molecule.
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