cloning简介.pptx

Cloning;In biology,?cloning?is the process of producing similar populations of genetically identical individuals that occurs in nature when organisms such as?bacteria, insects?or?plants?reproduce?asexually. Cloning in?biotechnology?refers to processes used to create copies of?DNA?fragments (molecular cloning),?cells?(cell cloning), or?organisms. The term also refers to the production of multiple copies of a product such as?digital media?or?software.;Cloning is the asexual production of an exact copy of an original. So for example, one could use cloning to produce the exact copy of a single cell. The cell copy would be identical to the first cell and would have the same exact DNA sequence. In many cases, cloning has been used to reproduce type specific cells. In some instances, cloning of an individual organism, like the sheep, Dolly, has been possible.;;Dollys birth was a real breakthrough, for it proved that something that had been considered biologically impossible could indeed be done. ; The film depicts a?dystopian?Los Angeles?in which genetically engineered?replicants, which are visually indistinguishable from adult humans, are manufactured by the powerful Tyrell Corporation. The use of replicates on Earth is banned and they are exclusively utilized for dangerous or menial work on?off-world colonies. ;Replicants who defy the ban and return to Earth are hunted down and killed (retired) by special police operatives known as Blade Runners. The plot focuses on a group of recently escaped replicants hiding in L.A. and the burnt-out expert Blade Runner,?Rick Deckard?(Harrison Ford), who reluctantly agrees to take on one more assignment to hunt them down.;Jurassic World is a 2015 American adventure science fiction film and the fourth installment of the Jurassic Park series. Set twenty-two years after the events of Jurassic Park, Jurassic World takes place on the same fictional island of Isla Nublar, off the Pacific coast of Central America, where a fully functioning