精英家教网 > 高中英语 > 题目详情

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.

练习册系列答案
相关习题

科目:高中英语 来源: 题型:阅读理解

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."
Of course,some teens do volunteer work because it looks impressive on their college applications.Lyons said he mentioned his trip on his submissions.But charity work is a habit with him.Even before the cross?country trip,he was volunteering about 200hours a year at various places.He's made sandwiches for homeless families in Washington D.C.He's taught math to fifth-graders in Cuernavaca,Mexico.
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
C.young people don't work hard
D.adults prefer to be volunteers
59.Russell Lyons has been doing volunteer work because.D
A.it is necessary for college applications
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.

查看答案和解析>>

科目:高中英语 来源: 题型:选择题

14.I can hardly remember any occasions _______ I get caught in a traffic jam in our town.(  )
A.whichB.thatC.whereD.when

查看答案和解析>>

科目:高中英语 来源: 题型:阅读理解

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.
I found her along a road,with a heavy chain wrapped around her neck,still attached to rotten boards from her doghouse.Not only did I know that most of the town people had already ignored her,judging by where I found her,but I knew that if she had gotten into the Woods,the"cross"that she dragged behind her would have wrapped around a tree until starvation or thirst killed her.She has a beautiful name now.Already in the first week she has come to look more like she should.Her eyes sparkle and she has learned to wag her tail in greeting.She has stopped flinching (畏缩) when I make a sudden movement,because she knows now that I won't beat her,in fact,she rarely leaves my side.She's even become brave enough to bark at a cat and today I watched from the window as she attempted to play with the other dogs.No,it's clear she does not miss you or her former life on a chain.
It's not clear yet whether she'll remain here or whether I'll find her a loving home where she can count on more individual attention than I can give her,but one thing is certain,this is one bit of stolen"property"who is never returning to you.So sue me,accuse me,plead with the courts that she is rightfully yours…I'm convinced this is the best"crime"I've ever committed.Hardly anything has pleased me more than the day I stole your dog.I need only look into her beautiful brown eyes to know that she'd defend my decision with her life.If we have one prayer,it is that you will not replace her,and if we have one special day to celebrate together,it is the day I stole your dog and the day she stole my heart.

41.What's the author's attitude towards the former owner of the dog?B
A.Puzzled.B.Angry.C.Shocked.D.Satisfied.
 42.It can be inferred from the passage thatC.
A.the dog is not lovely
B.the dog tried to find a kind master
C.the dog was treated badly by its former master
D.the author will be charged with stealing a dog
43.All the following statements showed us the dog's recovery from her nature exceptC.
A.playing with other dogs                 
B.barking at a cat
C.not missing her former master            
D.waving her tail to make greetings
44.What did the author think of his theft?D
A.He was afraid of being punished.
B.He thought he had to do it.
C.He believed that the law would allow him to do so.
D.He did it with pride.
45.What's the purpose did the author write the passage?B
A.To warn the people in the town not to keep dogs.
B.To prove his love to the dog to her former owner.
C.To explain to the police why the dog were in the Woods.
D.To ask people to find the dog a loving home and a owner who loves dogs.

查看答案和解析>>

科目:高中英语 来源: 题型:填空题

18.Part of the challenge in becoming better at a teaching job is getting to know the range of tools available.The following information focuses on what materials and equipment are available to make language teaching more effective.
The dictionary
The dictionary is a very handy tool.(36)D But sometimes,it can be in a large enough size to sit down for dinner at!They can be in hard or soft covers,corpus or non-corpus based,in book,pocket computer or CD-ROM form.
The board
The board is another standard piece of equipment that we may use often.There are all sort s of boards,such as flannel boards and black and green boards.(37)B Whiteboards of all sizes,from no bigger than a poster to those covering an entire wall,can be available in the market.
The box of rods
Apart from the above two common tools,the rods are slightly more unusual in the tool box.Manufactured by the Cuisenaire Company and originally used for teaching maths,rods are little sticks in ten different colors.(38)G
The picture pack
(39)AYou can select them for their beauty,strangeness,humor or other reasons.A picture pack can be used to review vocabulary,play guessing game,create stories and so on.(40)E
The music tape
Music is universal.Ask students to listen with their eyes closed and see what mental pictures they get.Not only can it create a good learning environment,but also it makes students more imaginative.

A.Collect about 50pictures cut from magazines.
B.Whiteboards are particularly used most.
C.Dictionary is very important in learning language.
D.Usually,dictionaries can be in a small pocket size.
E.In this way,students can study more effectively.
F.A picture pack is lightweight and portable.
G.Later,they became popular in language teaching.

查看答案和解析>>

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.

查看答案和解析>>

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:阅读理解

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

查看答案和解析>>

科目:高中英语 来源:2017届天津市河北区高三总复习质量检测(二)英语试卷(解析版) 题型:单项填空

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

查看答案和解析>>

科目:高中英语 来源: 题型:填空题

18.With a beautiful view of the East Lake and within easy reach of public facilities,those apartmentshave been sold out/were sold out(卖完了)in a week.(sell)

查看答案和解析>>

同步练习册答案