The discovery of the structure of DNA by Watson & Crick

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Running Head : DISCOVERY OF THE STRUCTURE OF DNA

The Discovery of the Structure of DNA by Watson Crick (Name (Institution (Grade Course (Tutor 's Name

Mar 20 , 2008

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It was around 1940 when researchers discovered , from studies in simple fungi , that genetic information consists primarily of instructions for making proteins . Here , proteins are the macromolecules that perform most cellular functions such as the building blocks for cellular structures and form the enzymes that catalyze all of the cell 's chemical reactions they regulate gene expression , and they enable

cells to move and to communicate with each other . The properties and functions of a cell are determined almost entirely by the proteins it is able to make . With hindsight , it is hard to imagine what other type of instructions the genetic information could have contained (Wilkins , 2003

Before biologists and researchers understood the structure and composition of DNA , they had recognized that genes are carried on chromosomes . This was discovered in the nineteenth century as thread like structures in the nucleus of a eucaryotic cell that become visible as the cell begun to divide . Later , as biochemical analysis became possible , chromosomes were found to consist of both DNA and protein From these we came to know that the DNA carries the hereditary information of the cell . On the other hand , the protein components of chromosomes function largely to package and control the enormously long DNA molecules so that they fit inside cells and can be easily accessed by them

Some of the famous and first researchers to discover and work with DNA were Maurice Wilkins and Rosalind Franklin . Maurice Wilkins was the director of a lab which was dedicated to studying the structure of macromolecules and other molecules and they were more interested in DNA Rosalind Franklin was the researcher who was working on this project Wilkins was instrumental in obtaining extremely pure DNA samples from another lab , and Franklin was perhaps one of the best , and certainly one of the most meticulous X-ray crystallographers of her time . Franklin was able to produce photos from fibers of DNA in a hydrated and dehydrated state . Since the DNA was less paired in the presence of water , then the hydrated DNA formed a less detailed diffraction pattern . By contrast , a very detailed

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pattern was exhibited from the dehydrated state , so Franklin decided to focus on trying to solve the structure of that form , and essentially put the hydrated form in a drawer . This data was later shared with Watson and Crick by Wilkins without Franklin 's knowledge . Crick and Watson then used the unorthodox method of model building to rapidly use the small amount of data to solve the structure of B-form DNA . Based on this model , Franklin was able to quickly make sense of the A-form from the other information that she had and she published its structure as well (Watson , 2004 ,

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The Human Genome Project denoted by HGP is an international project that took 13 years...