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Cloning is the most (41) ______ (attract) story of the new biotechnologies and the one (42) ______ causes the most heated discussion (43) ______ its worth.Cloning is the creation of cells or whole animals(44) ______ (use) DNA from a single"parent",by passing the normal productive process.The clone has the same DNA (45) ______ the parent.Clones are always produced (46) ______ natural means in the shape of identical twins.The most common process takes DNA from one cell and puts it in (47) ______ hollowed-out egg.Chemicals and electricity are then used to encourage the new DNA to fuse with the egg and develop into an embryo.This technique(48) ______ nuclear transfer.
A number of people have said they will make live human clones,including Chicago physicist Dr.Richard Seed.(49) ______ ,few experts believe that these people have the skills to succeed.In the UK,human cloning is already banned by law.President Bill Clinton has suggested(50) ______ (ban) any research into producing human clones in the US for five years.Some measures have also been made to establish international agreements banning live human clones.