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History_Of_Cloning

2013-11-13 来源: 类别: 更多范文

History Of Cloning The History of Cloning The theory of being able to make a genetic copy (a clone) of another animal has been around for quite a while. In this section as the title reads I will show the history of cloning. 400 million years B. C.- Plants have been cloning themselves since not to long (as far as the Earth is concerned) after their introduction to our planet. They send out runners that create an identical copy of the parent plant. 1938- Hans Spermann, of Germany, envisions what he calls the "fantastical experiment". He suggests taking the nucleus from a cell in the late-stage embryo and transplanting that nucleus into an egg. 1952- Scientists Robert Briggs and T.J. King use a pipette to suck the nucleus from the cell of an advanced frog embryo, they then add it to a frog egg. The egg didn't develop. 1970- John Gurdon tries the same experiment with the same procedure. The eggs developed into tadpoles but died after they were ready to begin feeding. He later showed that transplanted nuclei revert to an embryonic state. 1973- Ian Wilmut just finishes his doctorate at Cambridge University when he produces the first calf born from a frozen embryo. Cows only give birth to five to ten calves in a lifetime. By cloning, sheep, out, one, human, animals, clone, cells, plant, cell, mouse, humans, embryo, people, new, embryos, different, cloned, think, report, nucleus, because, another, take, just, identical, egg, dolly, book, adult, time, should, scientists, same, research
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