It was 10 years ago, on a warm July night, that a newborn lamb took her firs

游客2023-08-22  20

问题     It was 10 years ago, on a warm July night, that a newborn lamb took her first breath in a small shed in Scotland. From the outside, she looked no different from thousands of other sheep born on【C1】______farms. But Dolly, as the world soon came to realize, was no【C2】______lamb. She was cloned from a single cell of an adult female sheep,【C3】______long-held scientific dogma that had declared such a thing biologically impossible.
    A decade later, scientists are starting to come to grips with just how different Dolly was. Dozens of animals have been cloned since that first lamb—mice, cats, cows and, most recently, a dog—and it’s becoming【C4】______clear that they are all, in one way or another, defective.
    It’s【C5】______to think of clones as perfect carbon copies of the original. It turns out, though, that there are various degrees of genetic【C6】______. That may come as a shock to people who have paid thousands of dollars to clone a pet cat only to discover that the baby cat looks and behaves【C7】______like their beloved pet—with a different-color coat of fur, perhaps, or a【C8】______different attitude toward its human hosts.
    And these art just the obvious differences. Not only are clones【C9】______from the original template(模板)by time, but they are also the product of an unnatural molecular mechanism that turns out not to be very good at making【C10】_______ copies. In fact, the process can embed small flaws in the genes of clones that scientists are only now discovering.
A)abstract I)nothing
B)completely J)ordinary
C)deserted K)overturning
D)duplication L)separated
E)everything M)surrounding
F)identical N)systematicaly
G)increasingly O)tempting
H)miniature [br] 【C1】

选项

答案 M

解析 该空格位于名词farms之前,介词on之后,故空格处所填词应该是形容词,在句中作定语。根据句意,多莉羊从外表上看和周围的农场上出生的上千只小羊羔没有任何区别,故选surrounding,修饰farms,表示“附近的农场”。备选项里形容词较多,但很多不适合修饰农场,identical和ordinary虽然可以与farms搭配,但是都不符合句意,故排除。
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