Word: acidizing
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Brave words?and in a sense, incredibly true. On that late winter day in 1953, the two unknown scientists had finally worked out the double-helical shape of deoxyribonucleic acid, or DNA. In DNA's famed spiral-staircase structure are hidden the mysteries of heredity, of growth, of disease and aging?and in higher creatures like man, perhaps intelligence and memory. As the basic ingredient of the genes in the cells of all living organisms, DNA is truly the master molecule of life...
Scientists suspected that DNA had a helper, a single-stranded chemical first cousin called ribonucleic acid (RNA). Most of the cell's RNA is found in ribosomes. These are globular bodies in the material outside the cell's nucleus that seem to be highly active centers of protein synthesis. But if this ribosomal RNA played a role in protein making, how did it obtain and execute the instructions from the master molecule DNA inside the nucleus...
...National Institutes of Health, to crack the code itself. That same year Nirenberg had succeeded in building up short, synthetic strands of RNA out of only one type of base. Invariably, this artificial RNA induced the manufacture of chains of proteins consisting of only one type of amino acid, phenylalanine. The conclusion was inescapable: in the genetic code, Nirenberg's triplet had to signify phenylalanine...
...majority of genetic stigmas have somewhat more subtle symptoms and occur when defective genes fail to order the production of essential enzymes that trigger the body's biochemical reactions. Phenylketonuria (PKU) is caused by the absence of the enzyme necessary for the metabolism of the amino acid phenylalanine; as a result, toxins accumulate in the body and eventually cause convulsions and brain damage. Cystic fibrosis, which causes abnormal secretion by certain glands and respiratory-tract blockage that can lead to death by pneumonia, is the most common inborn error of metabolism; it is believed to be caused by a deficiency...
...that they can increase the life span of laboratory animals by underfeeding them and thus delaying maturation. This phenomenon, they believe, occurs because a smaller intake of food results in the formation of fewer cross linkages?connecting rods that link together and partly immobilize the long protein and nucleic acid molecules essential to life. If scientists can retard cross linking in man, they may well slow his aging process. Scientists also hope that they can some day do away with disease, genetically breeding out hereditary defects while breeding in new immunities to bacterial and other externally caused ailments. Finally, they...