Word: amino
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...last two decades scientists have found that DNA, a long double--chained molecule found in the nucleus, carries the cell's genetic information. This information is the blueprint that describes how the working parts of the cell, the proteins, should be assembled from 20 building blocks, the amino acids. Thus DNA ultimately determines the cell's function. The DNA's information is transferred to RNA (the cell's working manual), which is chemically like DNA except that it is usually single-stranded. Specific RNA messages ("messenger RNA") are shipped to the cytoplasm and there direct synthesis of the specific proteins...
...stopped the synthesis of all RNA by treating the cells with the specific antibiotic Actinomycin D, which is, incidentally, used to stop the growth of cancer cells. From then on, all protein synthesis depended on pre-existing messengers. He detected new protein molecules by exposing the cells to radioactive amino acids, which are incorporated into any protein the cell synthesizes. Kafatos has made thin sections of the cell and covered them with a thin photographic film. The radioactivity behaves like light and activated the film. His process is called autoradiography. He could then develop the film, count the activated silver...
...their onset. Months or even years before the physical signs appear, there are changes in mental processes. To Pauling, this suggests simply that the brain is more sensitive than most other organs to even a mild deficiency. He would broaden the range of "essential nutrilites" to include vitamins, amino acids and fatty acids, and probably a host of other substances. He would also widen the range of emotional illnesses for which biochemical causes, or at least components, should be sought...
...Hodgson flashed a continuous electric arc through a mixture of ammonia, methane and water vapor at NASA's Ames Research Center, near San Francisco. The arc simulated lightning, and the mixture was similar to the atmosphere that most scientists believe existed before life began. In addition to the amino acids, proteins, nucleotides and other life-foundation molecules that were created in previous experiments-some by Ponnamperuma himself-a small amount of an unidentified substance was produced...
Giant Crater. In a related experiment, Ponnamperuma and NASA Chemist Fritz Woeller flashed artificial lightning through a mixture of ammonia and methane simulating Jupiter's atmosphere. Besides producing amino acids and other organic materials that have led experimenters to speculate that primitive life could exist in the Jovian atmosphere, the discharges created large quantities of a translucent, ruby-red organic dye. This dye, the scientists speculate, may well explain the mark on Jupiter's surface, 30,000 miles long and 8,000 miles wide, that astronomers call the Great Red Spot...