Word: rna
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...creatures called planarians, or flatworms, that he has published in his own journal, The Worm Runner's Guide, and elsewhere. His work, which has been confirmed by only some of the researchers who have tried to duplicate his expermiments, suggests that memory storage is in some way related to RNA, the gigantic molecule which is also involved in cell reproduction. He exploited the remarkable regenerative powers of the planarian to demonstrate that both halves of a bisected worm will contract in the presence of light if the worm has been so conditioned before the operation is performed. In his words...
...Rubin, once a postdoctoral fellow in Dr. Dulbecco's lab, worked with viruses that cause leukemia in fowl and have a nucleus consisting of ribonucleic acid (RNA). The work of these men, said the awards committee, "promises to contribute decisively to our eventual understanding of the nature of cancer...
...only those parts of the DNA molecule that contain a few items of chemical instructions needed for metamorphosis. The parts become suddenly active; they swell up, forming visible puffs which show that the hormone has told them to do their stuff. Dutifully they release their information by forming "messenger RNA" (ribonucleic acid) that diffuses into the body of the cell and manufactures the protein enzymes that bring about metamorphosis. Then the puffs disappear, and the chromosomes wait for other hormones to come along and tell them to release other items of information...
...Wolfgang Beerman of West Germany's Max Planck Institute showed pictures of ropy, wormlike chromosomes with strange swellings, and reported on the delicate experiments with which he proved that the swellings are associated with active genes. Geneticists agree that active genes produce RNA (ribonucleic acid) and that RNA produces proteins. Dr. Beerman satisfied himself as to the meaning of the swellings he had photographed through his electron microscope, by finding RNA and protein where theory predicted they should be-right around the lumps on the chromosomes...
...chemical with a 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...