As if there weren’t enough of them in the world already, scientists have succeeded in cloning flies. The alike fruit flies are the first insects ever cloned, says the Canadian team that created them. The question everyone asks is why anyone would want to clone flies in the first place. She hopes that the insects , which are very easy to experiment with , will help to adjust the cloning process in other animals and even in humans, where the technique is being researched to aid production of therapeutic (治疗的) stem cells.
In cloning, the DNA-containing nucleus of an adult cell is injected into an egg whose own nucleus(细胞核) has been removed. At the moment, the majority of cloned mice, sheep and other animals die before birth. It is thought this is because the adult DNA is not properly ‘reprogrammed’.
Using flies, researchers might discover genes that are important for this reprogramming, and that have matches in other animals. That is because it is relatively easy in flies to knock out the function of a single gene and then attempt cloning with these cells, which will test whether that gene is important. If such genes are confirmed, then in theory cloned mammalian embryos(晶胚) might be grown in selected solutions that change the activity of those genes to improve the technique’s success rate. Although some groups have attempted to clone insects before, Lloyd says this is the first time it has been successful. The team used a slight difference on the standard cloning process: they transferred nuclei taken from embryos rather than fully-grown adult cells. They sucked several nuclei (pl)out of developing fly embryos, and injected them into a fertilized(已受精的) fly egg. From over 800 early attempts, they cloned five adult insects, the group reports in the journal Genetics.
1.The best title of this passage probably is _______.
A.The importance of clone
B.First insects are cloned
C.The disagreement in clone
D.The advantages of clone
2.The scientists cloned flies because________.
A.there are fewer and fewer flies in the world
B.flies are easy to find and cheap to use
C.they can gain some experience before cloning other animals
D.it is safe to clone flies
3.The failure of most cloned animals is due to _______.
A.the difference of other animals’ genes
B.the improper technique of clone
C.the complex of other animals
D.the improper rearrange of the adult gene
4.It can be inferred from the last paragraph that ______.
A.the clone of insects before used grown-up cells
B.the clone of insects were never experimented before
C.this time scientists cloned flies successfully and easily
D.based on this success, other animals will be cloned in large quantities.
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A. | which | B. | that | C. | where | D. | when |
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科目:高中英语 来源:2016-2017学年辽宁省鞍山市高二下学期期中考试英语试卷(解析版) 题型:短文改错
假定英语课上老师要求同桌之间交换修改作文,请你修改你同桌写的以下作文。文中共有10 处语言错误,每句中最多有两处。错误涉及一个单词的增加、删除或修改
增加:在缺词处加一个漏字符号(∧),并在其下面写出该加的词。
删除:把多余的词用斜线(\)划掉。
修改:在错的词下划一横线,并在该词下面写出修改后的词。
注意:1.每处错误及其修改均仅限一词:
2.只允许修改10处,多者(从第11处起)不计分。
Three years before, like many another girls who were addicted to novels, I was crazy about original English novels. Despite of the fact that many people around me thought that I had no talent for foreign languages, for I often failed pass my English exams, I was determined to read one chapter the day. Though I often couldn't understand, 1 was confident just because I was interested in English novels. Finally, my perseverance pays off and I made a tot of progresses in English. This experience has made me firm believe that it really matters on my way to success is interest.
Interest does have a big influence on myself, which I think will without doubt benefit my future career.
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Sometimes when I’m flying from one speaking engagement to another, I find myself sitting next to someone who's quite talkative. This is often a pleasant experience for me because I’m a people-watcher. I learn so much by watching and listening to the people I meet and see every day. I’ve heard stories of sadness and others of delight, fear and joy, and others that would rival those on “Oprah” and "Geraldo”.
Sad to say,there are times when I’m sitting next to someone who just wants to vent(发泄) his temper or inflict(强加)his political views on an audience for 600 miles. It was one of those days. I settled in, as my seatmate began his speech on the terrible state of the world with the time worn, “You know, kids today are...” He went on and on, sharing vague notions of the terrible state of teens and young adults, based on watching the six o’clock news rather selectively.
When I gratefully got off that plane and finally made it to my hotel in Indianapolis, I bought the local paper and went to have dinner in the hotel. There, on an inside page, was an article I believe ought to have been the front-page headline news.
In a little Indiana town, there was a 15-year-old boy with a brain tumor. He was undergoing radiation and chemotherapy(化疗)treatments,As a result of those treatments, he had lost all of his hair. I don’t know about you, but I remember how I would have felt about that at his age ---I would have felt awkward and ashamed.
This young man’s classmates willingly came to the rescue: all the boys in his grade asked their mothers if they could shave their heads so that Brian wouldn’t be the only bald boy in the high school. There, on that page was a photograph of a mother shaving all of her sons’ hair with the family looking on approvingly. And in the background, a group of similar bald young men.
No, I don’t despair about kids today.
1.From the passage we can infer the author's job is .
A. meeting talkative people
B. the commitments concerning speaking, like lecturers
C. a psychologist
D. to cope with complaints
2.The word “rival” in the first paragraph could best be replaced by .
A. oppose B. compete against
C. object to D. match
3.What's the author’s attitude towards his seatmate?
A. Favorable. B. Critical.
C. Indifferent. D. Satisfied.
4.The author's purpose in telling the news about the 15-year-old boy is .
A. to show his disappointment in kids today
B. to praise the diseased boy’s bravery
C. to draw people’s attention to care for such people
D. to display his confidence and faith in today’s teens
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It’s said that the power plant is now___ large as what it was.
A. twice as B. as twice C. twice much D. much twice
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