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With only about 1,000 pandas left in the world, China is desperately trying to clone (克隆) the animal and save the endangered species(物種). That's a move similar to what a Texas A&M University researchers have been undertaking for the past five years in a project called “Noah's Ark”.
Noah's Ark is aimed at collecting eggs, embryos(胚胎),semen and DNA of endangered animals and storing them in liquid nitrogen(氮). If certain species should become extinct , Dr. Duane Kraemar, a professor in Texas A&M University Medicine, says there would be enough of the basic building blocks to reintroduce the species in the future.
It is estimated that as many as 2,000 species of mammals , birds reptiles will become extinct in over 100 years . The panda, native only to China , is in danger of becoming extinct in the next 25 years .
This week , Chinese scientists said they grew an embryo by introducing cells from a dead female panda into the egg cells of a Japanese white rabbit . They are now trying to implant the embryo into a host animal.
The entire procedure could take from three to five years to complete.
“The nuclear transfer(核子移植) of one species to another is not easy, and the lack of available(capable of being used) panda eggs could be a major problem,” Kraemer believes. “They will probably have to do several hundred transfers to result in one pregnancy(having a baby). It takes a long time and it’s difficult, but this could be groundbreaking science if it works. They are certainly not putting any live pandas at risk, so it is worth the effort, ”adds Kraemer, who is one of the leaders of the Project at Texas A & M, the first–ever attempt at cloning a dog.
“They are trying to do something that’s never been done, and this is very similar to our work in Noah’s Ark. We’re both trying to save animals that face extinction. I certainly appreciate their effort and there’s a lot we can learn from what they are attempting to do. It’s a research that is very much needed.”
【小題1】 The aim of “Noah’s Ark” project is to ________.

A.make efforts to clone the endangered pandas
B.save endangered animals from dying out
C.collect DNA of endangered animals to study
D.transfer the nuclear of one animal to another
【小題2】According to Professor Kraemer , the major problem in cloning pandas would be the lack of _______.
A.a(chǎn)vailable panda eggsB.host animals
C.qualified researchersD.enough money
【小題3】The best title for the passage may be ______.
A.China’s Success in Panda Cloning
B.The First Cloned Panda in the World
C.Exploring the Possibility to Clone Pandas
D.China---the Native Place of Pandas Forever

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E
Every year farmers in areas which often suffer flood in Southeast Asia lose millions of tons of rice to high water that kills their crops. That large amount of waste may soon be a thing of the past: SUBIA, a gene discovered by researchers which the International Rice Research Insitule (IRRI) and the University of California, allows rice palnts carrying the gene to live completely under water for two weeks.
Flood – resistant(抗水浸) rice turned up among the 110,000 types of seed stored at the institute. It produced disappointingly low yields(產(chǎn)量) , but scientistis were able to transfer the gene into more bountiful varieties. These have shown promising results in tests by growers in India and Bangladesh over the past two years.
This rice success story would not have been possible without the treasure of genetic diversity hidden in the IRRI’s vault (underground room). As the world faces new agricultural challenge – charging climate, bugs and diseases that have developed resistance(抵抗力) to old defenses – such genetic resources are likely to become increasingly valuable. Fortunately, the IRRI is one of more than 1,000 organizations around the world working to protect crop genes. Most plant species grown for food have an associated bank that stores thousands of samples; seeds of landraces, wild relatives, and varieties that are rare, old, or adapted to very specific envionments. The banks ensure that it will be possible to develop new varieties in the future.
The need for these botanical libraries has its roots in modern agricultural practices. According to the U. N. Food and Agriculture Organization, 75 percent of plant diversity has been lost over the last century. Of more than 30,000 eatable species, humans grow just 200 for food; 60 percent of plant calories in our diet comes from wheat, rice, and corn.
72.Accordint to the second paragraph, what can we learn about the flood – resistant rice?
A.It produces a small amount of rice.
B.Scientists have developed many more varieties of it.
C.Sientists have managed to improve its output.
D.It can produce more rice than the other 110,000 types at the institute.
73.From the passage we can infer that        .
A.the newly – discovered gene will bring hope to the farmers in the areas often suffering flood
B.scientists will not be able to change the fact that rice plants carrying the gene produce low yields
C.the tests by growers in India and Bangladesh were hopeless
D.110,000 types of seed stored at the Institute are flood -  resistant
74.What’s the main idea of the third paragraph?
A.The world faces new agricultural challenges.
B.Such genetic resources are likely to become valuable.
C.Scientists set up banks to store thousands of seed samples.
D.We should owe the rice success story to the seed banks.
75.As to the botanical libraries, the writer thinks they are            .
A.useless      B.unnecessary      C.needful     D.needless

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D
With only about 1, 000 pandas left in the world, China is desperately trying to clone(克隆) the animal and save the endangered species(物種). That’s a move similar to what a Texas A & M University researchers have been undertaking for the past five years in a project called “Noah’s Ark”.
Noah’s Ark is aimed at collecting eggs, embryos(胚胎), semen and DNA of endangered animals and storing them in liquid nitrogen. If certain species should become extinct, Dr. Duane Kraemer, a professor in Texas A & M’s College of Veterinary Medicine, says there would be enough of the basic building blocks to reintroduce the species in the future.
It is estimated that as many as 2, 000 species of mammals, birds reptiles will become extinct in over 100 years. The panda, native only to China, is in danger of becoming extinct in the next 25 years.
This week, Chinese scientists said they grew an embryo by introducing cells from a dead female panda into the egg cells of a Japanese white rabbit. They are now trying to implant the embryo into a host animal.
The entire procedure could take from three to five years to complete.
“The nuclear transfer(核子移植) of one species to another is not easy, and the lack of available(capable of being used) panda eggs could be a major problem,” Kraemer believes. “They will probably have to do several hundred transfers to result in one pregnancy (having a baby). It takes a long time and it’s difficult, but this could be groundbreaking science if it works. They are certainly not putting any live pandas at risk, so it is worth the effort,” adds Kraemer, who is one of the leaders of the Project at Texas A& M, the first-ever attempt at cloning a dog.
“They are trying to do something that’s never been done, and this is very similar to our work in Noah’s Ark. We’re both trying to save animals that face extinction. I certainly appreciate their effort and there’s a lot we can learn from what they are attempting to do. It’s a research that is very much needed.”
69. According to Professor Kraemer, the major problem in cloning pandas would be the lack of _______.
A. available panda eggs                     B. host animals
C. qualified researchers                     D. enough money
70. The best title for the passage may be _______.
A. China’s Success in Pandas Cloning   
B. The First Cloned Panda in the World
C. Exploring the Possibility to Clone Pandas
D. China —the Native Place of Pandas Forever
71. From the passage we know that _______.
A. Kraemer and his team have succeeded in cloning a dog
B. scientists try to implant a panda’s egg into a rabbit
C. Kraemer will work with Chinese scientists in clone researches
D. about two thousand of species will probably die out in a century

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During the years after the terrorist attack on the World Trade Center, structural engineers have been trying hard to solve a question that would otherwise have been completely unthinkable: Can building be designed to stand catastrophic blasts (攻擊;爆破) by terrorists?
Soon after the terrorist attacks on the twin towers, structural engineers from the University at Buffalo and the Multidisciplinary Center for Earthquake Engineering Research (MCEER) traveled to ground zero as part of a project funded by the National Science Foundation. They spent two days beginning the task of formulating (構(gòu)思) ideas about how to design such structures and to search for clues on how to do so in buildings that were damaged, but still are standing.
“Our objective in visiting ground zero was to go and look at the buildings surrounding the World Trade Center, those buildings that are still standing, but that sustained damage,” said Mr. Bruneau, Ph.D. “Our immediate hope is that we can develop a better understanding as to why those buildings remain standing, while our long-term goal is to see whether earthquake engineering technologies can be married to existing technologies to achieve enhanced performance of buildings in the event of terrorist attacks,” he added.
Photographs taken by the investigators demonstrate the monumental damage to the World Trade Center towers and buildings nearby. One building a block away from the towers remains standing, but was badly damaged. “This building is many meters away from the World Trade Center and yet we see a column (柱子) there that used to be part of that building,” explained A. Whittaker, Ph.D. “The column became a missile that shot across the road, through the window and through the floor.”
The visit to the area also brought some surprises, according to the engineers. For example, the floor framing (框架) system in one of the buildings was quite strong , allowing floors that were pierced by tons of falling debris (殘礫) to survive. “Good framing systems may provide a simple, but reliable strategy for blast resistance,” he added. Other strategies may include providing alternate paths for gravity loads in the event that a load-bearing column fails. “We also need a better understanding of the mechanism of collapse,” said A. Whittaker. “We need to find out what causes a building to collapse and how you can predict it.”
A. Reinhorn, Ph.D. noted that “earthquake shaking has led to the collapse of buildings in the past. Solutions developed for earthquake-resistant design may apply to blast engineering and terrorist-resistant design. Part of our mission now is to transfer these solutions and to develop new ones where none exist at present.”
【小題1】The question raised in the first paragraph is one _____ .

A.that was asked by structural engineers a month ago
B.that is too difficult for structural engineers a month ago
C.that was never thought of before the terrorist attack
D.that terrorists are eager to find a solution to
【小題2】The column mentioned by Dr. Whittaker _____ .
A.was part of the building close to the World Trade Center
B.was part of the World Trade Center
C.was shot through the window and the floor of the World Trade Center
D.damaged many buildings near the World Trade Center
【小題3】A surprising discovery made by the investigators during their visit to ground zero is that _____.
A.floors in the faraway buildings remained undamaged
B.some floor framing systems demonstrate resistance to explosion
C.complex floor framing systems are more blast resistant
D.floors in one of the buildings were pierced by tons of debris
【小題4】 What Dr. Reinhorn said in the last paragraph may imply all the following EXCEPT that _____.
A.blast engineers should develop new solutions for terror-resistant design
B.blast engineering can borrow technologies developed for terror-resistant design
C.solutions developed for earthquake-resistant design may apply to terrorist-resistant design
D.blast engineering emerges as a totally new branch of science

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Scientist Says ‘No’ to Human Cloning
“I’ve never met a human worth cloning,” says cloning expert Mark Westhusin from 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 cows and a cat.
They just might succeed in cloning Missy soon — or perhaps not for another five years.
Westhusin's experience with cloning animals leaves him upset by all this talk of human cloning. In three years of work on the Missy project, using hundreds upon hundreds of dog's 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(代孕的)mother. The wastage of eggs and the many spontaneously aborted(流產(chǎn),發(fā)育不全) fetuses(胎)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 has been ringing with people calling in hopes of duplicating their cats and dogs, cattle and horses. “A lot of people want to clone pets, especially if the price is right,” says Westhusin. Cost is no obstacle for Missy's mysterious billionaire owner; he's put up $3.7 million so far to fund A&M's research.
Contrary to some media reports, Missy is not dead. The owner wants a twin to carry on Missy's fine qualities after she does die. The prototype(原型;雛形)is, by all accounts, athletic, good-natured and supersmart. Missy's master does not expect an exact copy of her. He knows her clone may not have her temperament(氣質(zhì)、性情). In a statement of purpose, Missy's owner and the A&M team say they are “both looking forward to studying the ways that her clones differ from Missy.”
Besides cloning a great dog, the project may contribute insight into the old question of nature vs. nurture. It could also lead to the cloning of special rescue dogs and many endangered animals.
However, Westhusin is cautious about his work. He knows that even if he gets a dog 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?”
【小題1】By “stupid endeavor”, Westhusin means to say that ________.

A.human cloning is a foolish undertaking
B.a(chǎn)nimal cloning is absolutely impractical
C.human cloning should be done selectively
D.a(chǎn)nimal cloning is not worth the effort at all
【小題2】What does the first paragraph tell us about Westhusin's dog cloning project?
A.Its success is already in sight.
B.It is progressing smoothly.
C.It is doomed to utter failure.
D.Its outcome remains uncertain.
【小題3】By cloning Missy, Mark Westhusin hopes to ________.
A.study the possibility of cloning humans
B.search for ways to modify its temperament
C.find out the differences between Missy and its clones
D.examine the reproductive system of the dog species
【小題4】We learn from the passage that animal clones are likely to have ________.
A.a(chǎn) bad temper
B.defective(有缺陷的、有毛病的)organs
C.immune deficiency
D.a(chǎn)n abnormal shape

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