“ I’ve never met a human worth cloning,” says cloning expert Mark Westhusin from the cramped confines of his lab at Texas A&M University.“It’s a stupid endeavor.” That’s an interesting choice of adjective, coming from a man who has spent millions of dollars trying to clone a 13 year old dog named Missy.So far, he and his team have not succeeded, though they have cloned two calves and expect to clone a cat soon.They just might succeed in cloning Missy later this year — or perhaps not for another five years.It seems the reproductive system of man’s best friend is one of the mysteries of modern science.
Westhusin’s experience with cloning animals leaves him vexed by all this talk of human cloning.In three years of work on the Missyplicity project, using hundreds upon hundreds of canine eggs, the A&M team has produced only a dozen or so embryos carrying Missy’s DNA.None have survived the transfer to a surrogate mother.The wastage of eggs and the many spontaneously aborted fetuses may be acceptable when you’re dealing with cats or bulls, he argues, but not with humans.“Cloning is incredibly inefficient, and also dangerous,” he says.
Even so, dog cloning is a commercial opportunity, with a nice research payoff.Ever since Dolly the sheep was cloned in 1997, Westhusin’s phone at A&M College of Veterinary Medicine has been ringing busily.Cost is no obstacle for customers like Missy’s mysterious owner, who wishes to remain unknown to protect his privacy.He’s plopped down $3.7 million so far to fund the research because he wants a twin to carry on Missy’s fine qualities after she dies.But he knows her clone may not have her temperament.In a statement of purpose, Missy’s owners and the A&M team say they are “both looking forward to studying the ways that her clone differs from Missy.”
The fate of the dog samples will depend on Westhusin’s work.He knows that even if he gets a dog viably pregnant, the offspring, should they survive, will face the problems shown at birth by other cloned animals: abnormalities like immature lungs and heart and weight problems.“Why would you ever want to clone humans,” Westhusin asks, “when we’re not even close to getting it worked out in animals yet?”
21.Which of the following best represents Mr.Westhusin’s attitude toward cloning?
[ A ] Animal cloning is a stupid attempt.
[ B ] Human cloning is not yet close to getting it worked out.
[ C ] Cloning is too inefficient and should be stopped.
[ D ] Animals cloning yes, and human cloning at least not now.
22.The Missyplicity project does not seem very successful probably because .
[ A ] there isn ’ t enough fund to support the research
[ B ] cloning dogs is more complicated than cloning cats and bulls
[ C ] Mr.Westhusin is too busy taking care of the business
[ D ] the owner is asking for an exact copy of his pet
23.When Mr.Westhusin says “...cloning is dangerous,” he implies that .
[ A ] lab technicians may be affected by chemicals
[ B ] cats and dogs in the lab may die of diseases
[ C ] experiments may waste lots of lives
[ D ] cloned animals could outlive the natural ones
24.We can infer from the third paragraph that .
[ A ] rich people are more interested in cloning humans than animals
[ B ] cloning of animal pets is becoming a prosperous industry
[ C ] there is no distinction between a cloned and a natural dog
[ D ] Missy ’ s master pays a lot in a hope to revive the dog
25.We may conclude from the text that .
[ A ] human cloning will not succeed unless the technique is more efficient
[ B ] scientists are optimistic about cloning technique
[ C ] many people are against the idea of human cloning
[ D ] cloned animals are more favored by owners even if they are weaker
21. 【答案】 D
【解析】 观点态度题。文中多次引用了威斯苏森先生有关克隆的话，从中我们可以判断出他的态度。[ A ] 中 a stupid attempt 出现在文章开始部分，是他对于克隆人而非克隆动物的看法，因此[ A ] 错误。[ B ] 中 not yet close to getting it worked out 出现在文章末句，是他对待动物实验的看法，不包括克隆人，因此也不选[ B ] 。事实上，克隆人还没有开始，谈不上是否接近成功。第二段末句，威斯苏森先生提到克隆是极其低效的，但没有提出因此就应该被禁止。因此，[ C ]也错误。第二段倒数第二句，威斯苏森先生提出，动物实验中对动物卵的浪费以及动物的自然性流产还可以接受，但研究人就不行。可见，他默许克隆动物，但他反对克隆人，因此[ D ] 正确。
22. 【答案】 B
【解析】 细节题。第一段倒数第二句指出，克隆密斯可能成功也可能失败。该段最后一句解释其原因是：狗的生殖系统似乎是现代科学中一个神秘的领域，可见克隆狗更复杂。因此[ B ] 为正确项。第三段首句提到，克隆狗是一个商机，能带来丰厚的科研报酬。该段第三句又提到，对于像密斯的主人这样的消费者来说，高额的花销并不是什么障碍。由此可知，[ A ]不是项目不成功的原因。[ C ] 原文没有提及，第三段第二句只提到，多利羊克隆成功后，威斯苏森教授接到很多希望克隆狗的电话，这些电话都潜藏商机。但不能由此推知他忙于商业活动。第三段最后两句提到，密斯的主人知道，密斯的克隆体不一定能有与它一样的脾气秉性。在一份用途声明中，密斯的主人和农业机械大学的团队表示，他们“共同期待能研究密斯的克隆体与它本身的差异之处。”可见[ D ] 也不是原因。
23. 【答案】 C
【解析】 理解题。题干引用的话出现在第二段末。前一句话中威斯苏森先生提到在猫或牛的克隆试验中对动物卵的浪费以及许多动物的自然性流产，因此可知，[ C ]是“危险”的真正含义。其他项文中均未提及。
24. 【答案】 B
【解析】 推理题。第三段首句提到，克隆狗是能带来丰厚科研报酬的商机。下文举了两个例子进一步说明：动物医学院频繁接到电话，以及富人一掷千金想克隆爱犬，因此可以推出答案是[ B ] 。[ A ] 项文中没有提及，[ C ]与文意相反，[ D ]项原文中密斯的主人只是想要一个密斯的孪生子，而不是让密斯死后复活。
25. 【答案】 A
【解析】 细节题。文章一开始就引用专家威斯苏森的话，指出克隆人是愚蠢的尝试。第二段最后两句提到，克隆实验的低效性和危险性在克隆人中不可接受。文章末尾再次引用该专家的话，指出现在动物的克隆研究还没完全成功，没有必要想到克隆人。由此可见，技术是克隆实验存在的主要问题，也是阻碍克隆人实验的重要原因，因此可推知[ A ] 正确。[ B ] 明显错误，科学家并不乐观。全文只涉及专家和拥护克隆实验的人的观点，因此无法推知[ C ] 中的“许多人”。[ D ] 在文中没有提及。