Word: humanities
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Dates: during 1980-1989
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...concern, as well as the cost, reflects the complexity of the human genome and the magnitude of the effort required to understand it. DNA is found in the human-cell nucleus in the form of 46 separate threads, each coiled into a packet called a chromosome. Unraveled and tied together, these threads would form a fragile string more than 5 ft. long but only 50 trillionths of an inch across...
...building blocks of proteins. But the entire genome of even the simplest organism dwarfs that snippet. The genetic blueprint of the lowly E. coli bacterium, for one, is more than 4.5 million base pairs long. For a microscopic yeast plant, the length is 15 million units. And in a human being, the genetic message is some 3 billion letters long...
Like cartographers mapping the ancient world, scientists over the past three decades have been laboriously charting human DNA. Of the estimated 100,000-odd genes that populate the genome, just 4,550 have been identified. And only 1,500 of those have been roughly located on the various chromosomes. The message of the genes has been equally difficult to come by. Most genes consist of between 10,000 and 150,000 code letters, and only a few genes have been completely deciphered. Long segments of the genome, like the vast uncharted regions of early maps, remain terra incognita...
...most formidable tasks faced by geneticists is to learn the nature of that machinery and other genetic instructions buried in the lengthy, still undeciphered base sequences. To do so fully requires achievement of the project's most challenging goal: the "sequencing" of the entire human genome. In other words, the identification and listing in order of all the genome's 3 billion base pairs...
...formulated the laws of heredity and suggested the existence of packets of genetic information, which became known as genes. Soon afterward, chromosomes were observed in the nuclei of dividing cells, and scientists later discovered a chromosomal difference between the sexes. One chromosome, which they named Y, was found in human males' cells, together with another, called X. Females' cells, on the other hand, had two copies...