Word: dna
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Dates: during 1960-1969
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...essence of heredity-the delicately complex deoxyribonucleic acid known as DNA-has been extracted virtually intact from human sperm for the first time by Doctors Ellen Borenfreund and Aaron Bendich. The "almost impossible" feat promises to shed new light on the transmission of hereditary traits in mammals and on the origin of genetic abnormalities. After experiments with the sperm of fish and fowl, rabbits and bulls, the Manhattan researchers carefully washed the human sperm to rid it of enzymes, then treated the DNA tough protein topcoat with a chemical that freed the 400,000 chainlike DNA molecules for examination...
Four young scientists were among the new professors promoted from within the faculty: James D. Watson, 32, a biologist well known for the Watson-Crick model of the structure of Desoxyribonucleic acid (DNA), a long-chain molecule which determines hereditary traits in living cells; Richard Wilson, 34-years-old expert in high energy physics; Arthur E. Bryson, Jr., 35, whose field is missile stability and reentry heating; and Bernard Budiansky, 35, who has studied the structural problems of supersonic missiles...
When a cell reproduces by division, the DNA molecules in its nucleus have two jobs. First they must make perfect duplicates of themselves. Then they must control the formation of enzymes (protein catalysts) that will generate the other proteins that the cell needs to grow bigger and split...
...most direct way to achieve understanding of this system would be to find the exact structure of DNA, including the magical code. But when it is considered that the DNA molecules in human cells may have something like a million atoms all linked and twisted in a special way, the difficulties stagger imagination. So the attack on the molecules of life is mounted in other, more indirect ways. One approach is through genetics: learning about the chemistry of reproduction of small and comparatively simple organisms like molds. Another approach is through X-ray studies of proteins, with the X rays...
Despite such chilling challenges, the molecular biologists have the tingling feeling that they are about to break through the black unknown. Caltech's Geneticist George Beadle thinks that future understanding of DNA and proteins may tell why some cells of a developing embryo turn into skin, others into bone or brain. Caltech's Pauling, a physical chemist who shifted to biochemistry and proved that proteins have a coiled structure, believes that "very fundamental discoveries are now possible in this field. The foundation has been laid for men to make a penetrating attack on the nature of life." With deeper understanding...