Have you seen Jurassic Park? In this film, scientists use DNA kept for tens of millions of years to clone dinosaurs. They find trouble, however, when they realize that the cloned creatures are smarter and more dangerous than expected. That’s nothing more than a fiction.
But could we really clone endangered animals?
To date, the most successful attempt to do so was the cloning of a gaur, a rare ox-like animal from southeast Asia. Scientists used a cow to bring the cloned baby gaur, named Noah. Two days after birth, however, Noah died from a common bacterial infection. Other endangered species that may be cloned include the African bongo antelope (邦戈羚羊), the Sumatran tiger, the cheetah (猎豹), and the giant panda. Next, could we really clone extinct animals?
In theory? Yes. To do this, you need a well-kept source of DNA from the extinct animals such as wool mammoth (毛象), Tasmanian tiger, or even dinosaur, and a closely related species, still living, which could serve as a surrogate mother.
In reality? Probably not. On the one hand, it’s not likely that extinct animals’ DNA could survive undamaged for such a long time. Cloning extinct animals as wool mammoth, Tasmanian tiger, or dinosaur is much more difficult due to the lack of properly well-preserved DNA. On the other hand, for example, a gaur can have a cow as a surrogate mother, definitely not a monkey. But what about an extinct animals as unique as the panda? What species could possibly serve as a surrogate mother?
Cloning presents many exciting possibilities. However, even if extinct animals are brought back, they could not survive in today’s world. Not only do most extinct animals have no habitat to love in, but the other plants and animals they depended on for food may also be gone as well.
1. It can be learned from the text that ________.
A. scientists have cloned the African bongo antelope
B. both the cheetah and the giant panda live in Asia
C. the gaur lives in Asia and is endangered
D. the gaur is an extinct species
2. The underlined words “a surrogate mother” probably refer to a female who -----
A. contributes its eggs to another female B. gives birth to a baby for another female
C. gives birth to a baby of its own D. cannot give birth to a baby
3. The difficulty in cloning an extinct species is the lack of ______.
A. both the well-preserved DNA and plants to live on
B. both the habitat to live in and the well-preserved DNA
C. both habitat to live in and plants to live on
D. both the well-preserved DNA and a surrogate mother
4. In the author’s opinion, it is possible that ______.
A. some extinct species may be cloned, but not survive
B. extinct species may be cloned and easily survive
C. a gaur can have a monkey as a surrogate mother
D. all the extinct species may be cloned
5.Today , have scientists cloned dinosaus?
A .Yes B .No C .A lot D.Only one.
科目:高中英语 来源:2013-2014学年安徽省安师大附中高三1月联考英语试卷(解析版) 题型:单项填空
---Have you paid ? What’s my share of the bill?
---____. It wasn’t very much.
A. Don’t worry about it. B. It’s my share. C. None of your business. D. It’s up to you.
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科目:高中英语 来源:2012-2013学年江苏涟水中学高三第一次质量检测英语卷(解析版) 题型:完型填空
Martin was grown-up, and for his birthday that year his father gave him a 36 without any pictures in it!
Martin’s father found he was not 37 about it, and told him, “Son, this isn’t just any 38 book; it’s a magic (有魔力的) book. But to discover its magic you’ll have to 39 it.”
Well, that was better. Martin liked 40 to do with magic. He started reading it, 41 he wasn’t very willing to.
The next morning, his 42 asked him, “Have you found the magic 43 ? ”
So… there was a key to find! Martin flicked through (快速翻阅) the book, but there was no 44 of the key.
And then his father 45 him, “You won’t find it like that . You have to read the book.”
Martin didn’t have much patience (耐心), thinking his father just told a 46 . A little later, his little sister, Angela, asked him 47 the book. After several days, she 48 shouted, “I’ve found the key!” And she wouldn’t stop 49 all the places she had visited using the magic key.
This made Martin read the book again. At first it was a 50 ; there wasn’t even one single 51 in the book. But, gradually, Martin became 52 the adventurous (冒险的) prince’s life. Then, suddenly, he was there.
The book 53 was the key!
It was true that every time he 54 it, he felt going to its valleys and seas, and he lived the adventures of the prince.
From then on, with every new book, Martin never 55 being attracted by the letters and words inside.
1. A.box B.diary C.book D.bag
2. A.sad B.happy C.surprised D.angry
3. A.special B.new C.famous D.ordinary
4. A.keep B.read C.take D.value
5. A.somebody B.nothing C.everything D.anybody
6. A.so B.and C.though D.or
7. A.uncle B.mother C.father D.aunt
8. A.page B.word C.stick D.key
9. A.mark B.sign C.signal D.way
10. A.asked B.praised C.followed D.told
11. A.lie B.story C.joke D.will
12. A.of B.for C.to D.back
13. A.happily B.badly C.quickly D.slowly
14. A.working out B.talking about C.turning down D.looking for
15. A.pity B.pleasure C.pain D.success
16. A.picture B.note C.text D.title
17. A.busy with B.tired of C.interested in D.good at
18. A.it B.yourself C.himself D.itself
19. A.opened B.put C.threw D.covered
20. A.tried B.felt C.stopped D.began
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科目:高中英语 来源:2015届江苏宿迁青华中学高一下学期期中考试英语卷(解析版) 题型:阅读理解
Have you ever wondered why birds sing? Maybe you thought that they were just happy. After all, you probably sing when you are happy.
Some scientists believe that birds do sing some of the time just because they are happy. However they sing most of the time for a very different reason. Their singing is actually a warning to other birds to stay out of their territory.
Do you know what a ‘territory’ is? A territory is an area that an animal, usually the male, claims as its own. Only he and his family are welcome there. No other families of the same species are welcome. Your yard and house are your territory where only your family and friends are welcome. If a stranger should enter your territory and threaten you, you might shout. Probably this would be enough to frighten him away.
If so, you have actually scared the stranger away without having to fight him. A bird does the same thing. But he expects an outsider almost any time, especially at nesting(筑巢) season. So he is screaming all the time, whether he can see an outsider or not. This screaming is what we call a bird’s song, and it is usually enough to keep an outsider away.
Birds sing loudest in spring when they are trying to attract a mate and warn others not to enter the territory of theirs.
You can see that birds have a language of their own. Most of it has to do with attracting mates and setting up territories.
1.Some scientists believe that most of the time bird’s singing is actually _____________.
A.an expression of happiness B.a way of warning
C.an expression of anger D.a way of greeting
2.What does the underlined word“territory”mean?
A.A place where families of other species are not accepted.
B.A place where a bird may shout at the top of its voice.
C.An area for which birds fight a against each other.
D.An area which a bird considers to be its own.
3.Why do birds keep on singing at nesting season?
A.Because they want to invite more friends.
B.Because their singing helps frighten outsiders away.
C.Because they want to find outsiders around.
D.Because they want to express their happiness.
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科目:高中英语 来源:2012-2013学年黑龙江省高三第三次阶段英语试卷(解析版) 题型:完型填空
One of my fondest memories as a child is going by the river and sitting idly on the bank.There I would 36 the peace and quiet, watch the water rush 37 and listen to the singing of birds and the rustling of 38 in the trees.I would also watch the bamboo trees 39 under pressure from the wind and watch them 40 gracefully to their original position after the wind had 41 .
When I think about the bamboo tree's ability to bounce back to its original position, the word "resilience" comes to mind.When used in 42 to a person, this word means the ability to readily 43 from shock, depression or any other situation that stretches the limits of a person's 44 .
Have you ever felt like you are at your 45 point? Thankfully, you have survived the experience to live to talk about it.
During the 46 you probably felt a mix of emotions that threatened your health.You felt emotionally drained(枯竭), 47 exhausted and you most likely stood 48 physical symptoms.
Life is a 49 of good times and bad times, happy moments and unhappy moments.The next time you are experiencing one of those bad times or unhappy 50 that take you close to your breaking point, bend, 51 don't break.Try your best not to let the situation get the best of you.
A measure of hope will take you 52 the unpleasant ordeal (考验).With 53 for a better tomorrow or a better situation, things may not be as bad as they seem to be.The unpleasant ordeal may be easier to 54 if the final result is worth having.
If life gets 55 and you are at your breaking point, show resilience.Like the bamboo tree, bend, but don't break!
1. A.see B.hear C.touch D.enjoy
2. A.smoothly B.downstream C.uphill D.peacefully
3. A.fruits B.branches C.leaves D.roots
4. A.bend B.move C.fall D.decline
5. A.go B.turn C.return D.suffer
6. A.died away B.died off C.died down D.died out
7. A.honor of B.reward to C.favor of D.reference to
8. A.escape B.suffer C.come D.recover
9. A.emotions B.mind C.body D.thoughts
10. A.starting B.breaking C.standing D.tiring
11. A.practice B.experiment C.experience D.victory
12. A.possibly B.mentally C.terribly D.probably
13. A.unpleasant B.unreasonable C.exciting D.good
14. A.result B.change C.mixture D.wonder
15. A.moments B.events C.adventures D.changes
16. A.however B.but C.though D.and
17. A.away B.through C.apart D.out
18. A.idea B.search C.imagination D.hope
19. A.get stuck B.look into C.depend on D.deal with
20. A.tough B.wrong C.acceptable D.cozy
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科目:高中英语 来源:2015届吉林省高一上学期期中考试英语试卷(解析版) 题型:单项填空
–Have you heard that Tom has passed his driving test?
–Oh! That’s great of him! I’ll go and _____ him _____ that.
A. congratulate; for |
B. admire; for on |
C. admire; on |
D. congratulate; on |
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