题目内容

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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13.When Russell Lyons volunteered for the first time,he read"Goodnight Moon"to a class of San Diego preschoolers.And it wasn't reading-he'd memorized the book and was reciting it out loud.He was 4.Still,he said it felt good up there,in front of the other kids,lending a hand.He wanted more of that feeling.
Thirteen years later,he's getting a lot of it.He's on a five-month road trip across America-not sightseeing,but volunteering.
The University City resident has spent time at an animal reserve in Utah,a women's shelter in St.Louis,a soup kitchen in New York,a retirement home in Tucson.This week he's in Los Angeles,at a program that supports disabled youth.
"I just like helping people and feeling that something I do is making a difference,"he said.He resists the idea that his"Do Good Adventure"is all that unusual.It bothers him that the media often describe young people as lazy,self-centered and materialistic.So he sees his trip as a chance to make a statement,too."About 55percent of teens do volunteer work,higher than the rate for adults,"he said,according to a 2002 study."Not everybody knows that."
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He gets some of that drive from his mother,Leslye Lyons,who has been involved in nonprofits for much of her life.She was there when her son"read"to the preschoolers-a memory of hers"that will never go away."

56.What did Russell Lyons think of his first volunteering?B
A.Creative.  B.Impressive.  C.Persuasive.  D.Imaginative.
57.The third paragraph is meant to.A
A.indicate Russell Lyons is working as a volunteer
B.introduce some tourist attractions across America
C.appeal for volunteers to offer help to those in need
D.show volunteers are needed in all parts of America
58.According to Paragraph 4,Russell Lyons is against the idea that.C
A.what he has done is common
B.most teens do volunteer work
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D.adults prefer to be volunteers
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B.he ought to keep his promise to Mom
C.he likes the feeling of being praised
D.it has become a natural part of his life
60.What does the last paragraph suggest?B
A.Leslye Lyons is too busy to look after her son.
B.Russell Lyons is greatly influenced by his mother.
C.Leslye Lyons almost earns no money all her life.
D.Children are always important to their parents.
11.I stole your dog today.No,I didn't set a foot on your house,but from the condition of your dog,I can imagine what it looks like…the word"rubbish"comes to mind.
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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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