Word: rna
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...that J. D. Watson and company have outlined their construction manual for DNA (deoxribonucleic acid), the carrier of genetic information for all cells, many scientists agree that the best target for further research is RNA (ribonucleic acid). The cell copies specific genetic instructions from the DNA into RNA and then transports the RNA from the nucleus to the cytolpasm. It has not yet been determined how the cell chooses which information to copy and how the RNA is transmitted...
...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...
...reaction is more readily observable in animals, Hydén reported. When a normally lefthanded rat was forced to learn to use his right paw to get food out of a tube, cells in the most highly developed part of the brain (the cortex) produced a special kind of RNA as well as proteins. A similar thing happened in goldfish that were forced to learn a new kind of swimming by having buoyant plastic foam stuck under their chins by Dr. Victor Shashoua of M.I.T. Fish that Dr. Shashoua made work just as hard swimming against a current, but without...
...cells, said Hydén, seldom divide and replace themselves as do most other cells in the body. The neurons that a child has at six years must last him a lifetime. As he ages, some of them become damaged or die, so the brain's output of RNA in learning situations is decreased...
...brain's RNA and protein production are originally determined by deoxyribonucleic acid (the DNA of Biochemist James Watson's bestselling The Double Helix) that is established in the embryo by the sex cells at the time of conception. There is evidence, said Hydén, that the DNA in an old animal differs from that in a young one-and the same is true, presumably, in man. Here, Hydén opened the door a chink for a glimpse into an admittedly farout future. If a reasonably pure extract of brain DNA is injected into some animals...