Word: nucleic
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...contraceptive. Syntex then began selling the compound to other drug firms, later introduced its own pill. Both Syntex and Searle now obtain their diosgenin from Mexican yams, which grow wild in the jungles. Rosenkranz, now Syntex's president, has continued the company's research in hormones and nucleic acids, the basic substances of living cells...
Twentieth century geneticists gradually evolved the theory that whether an organism is to be microbe, mouse or man, its biochemical functions are determined by genes strung together to form chromosomes. Each gene is believed to be a submicroscopic but still "giant" molecule of a nucleic acid, usu ally deoxyribonucleic acid (DNAJ, but in some viruses ribonucleic acid (RNA) Each gene, the theory held, directly controls the cells' production of some one specific chemical-in most cases an enzyme, one of the body's countless catalysts that are essential to nearly all its functions...
With Stand-ins. To check and expand on these hypotheses, Lwoff chose to work with single-celled organisms, such as bacteria, because they have a single chromosome (whereas man has 46). As stand-ins for genes he chose viruses that infect bacteria (bacterio-phages), because their cores consist of nucleic acid. What actually happens Lwoff found, is not as simple as had been thought. The viral nucleic acid, in effect masquerading as a gene, might do one of two things after invading a bacterium: 1) stimulate the bacterial cell to produce hundreds of copies of the virus particle, and destroy...
...most of the free hydrogen in the earth's primitive atmosphere had escaped into space. Only then could adenine and similar chemicals have been made out of methane, ammonia and water. Gradually, those chemicals accumulated in the ocean where the first life appeared, and at last they formed nucleic acid, life's key substance...
...molecule made of two ordinary carbon-nitrogen rings. But to biochemists, it is one of the keys of life. It takes part in the formation of a long list of vital substances, and it is one of the five "bases" that are built into DNA and RNA, the magic nucleic acids that control the reproduction and heredity of all living organisms. Since the first life probably appeared on earth when chemicals already dissolved in sea water formed a giant molecule that had the power to reproduce itself, it is likely that this ancestral molecule was a nucleic acid...