Genetically modified(轉(zhuǎn)基因的) food remains ___________ nearly two decades after being introduced to the commercial market, as there is still no general agreement on whether it is harmful to humans.

A. conventional      B. contradictory        C. controversial       D. contrary

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科目：高中英語 來源：河北省正定中學2009-2010學年高二下學期期末考試試題（英語） 題型：閱讀理解


A breathtaking trick potentially left over from our ancestors might be found in us — the ability to sense oxygen through our skin.
Amphibians, animals such as frogs that can live both on land and in water, have long been known to be capable of breathing through their skin. In fact, the first known lungless frog that breathes only through its skin was discovered recently in the rivers of Borneo.
Now the same oxygen sensors found in frog skins and in the lungs of mammals (哺乳動物) have unexpectedly been discovered in the skin of mice.
“No one had ever looked,” explained Randall Johnson, a biologist researcher.
Mice and frogs are quite distant relatives, so the fact they have these molecules (分子) in common in their skin suggests they might well be found in the skin of other mammals, such as humans.
“We have no reason to think that they are not in the skin of people too,” Johnson said.   These molecules not only detect oxygen, but help increase levels of vital red blood cells, which carry oxygen around the body. Normal mice breathing in air that is 10 percent oxygen—a dangerously low level similar to conditions at the top of Mount Everest, and about half that of air at sea level. However, mice that had the oxygen sensor HIF-1a genetically removed from their skin failed to produce this hormone (荷爾蒙) even after hours of such low oxygen.
These findings, if they hold true in humans, suggest one could raise the level of oxygen circulating inside the body. This could help treat lung diseases and disorders such as anemia (貧血癥) without injecting drugs, which make up a multibillion-dollar market, Johnson said.
Athletes also often try to get more oxygen delivered to their muscles in order to improve their performance. They often do this by training at high altitudes or in low-oxygen tents. The new study suggests they might want to expose their skin as well as breathing in low-oxygen air to improve their performance. “It’s hard to say what exactly might be done, however—there’s a lot we don’t know yet,” Johnson explained.
The scientists detailed their findings in the April 18 issue of the journal Cell.
49. Which of the following statements is TRUE according to the passage?
A. Johnson believes that Oxygen sensors also exist in human skin.
B. People have to surf the Internet to read detailed findings.
C. It has been proved that these findings help treat lung diseases.
D. It has long been expected oxygen sensors exist in mice’s skin. 
50. One of the functions of the molecules mentioned above is _______.
A. carrying oxygen around the body                   B. improving athletes’ performance
C. detecting oxygen                                          D. increasing level of oxygen
51. What is Johnson’s attitude to the application of the findings to the athletes’ training?
A. Negative                  B. Doubting                  C. Positive             D. Hesitating
52. The best title of the passage may be _______.
A. Great Findings Benefits Athletes A Lot
B. Frogs And Mice Are Distant Relatives
C. First Known Animal Breathes Through Skin
D. Humans Might Sense Oxygen Through Skin

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科目：高中英語 來源：遼寧省沈陽市三校20092010學年高二下學期期中聯(lián)考英語試題 題型：閱讀理解

Bollworms are a traditional threat to cotton crops．Young ones feed on the boll, the part of the

cotton plant that contains the seeds．

 

A bacterium known as Bt is able to kill bollworms and some other pests．Bt is short form for Bacillus thuringiensis．It was discovered in the early twentieth century．Farmers began using Bt as a natural pesticide（殺蟲劑）．

Then，in the 1990s，researchers found a way to grow cotton plants that contain a Bt gene．The genetically modified cotton plant produces toxins that kill bollworms．Farmers around the world are now growing an estimated fourteen million hectares of Bt cotton．

Cotton bollworms also attack other crops．But scientists in China recently reported that Bt cotton may help suppress bollworm in other crops growing nearby．

The study involved crops grown in six provinces of northern China between 1992 and 2008.The study area contained three million hectares of cotton and twenty-two million hectares of corn，peanuts，soybeans and vegetables．

The researchers say the study suggested that Bt cotton not only controls bollworm on the transgenic cotton，but also may reduce its presence on other crops．And that reduction，they say，may decrease the need for insecticide use in general．

But the researchers also pointed out concerns．They say bollworms could develop resistance to the cotton plants designed to resist them．And they noted that insects called mirids have become “key pests” of cotton in China．They said this is because of a decrease in pesticide use made possible by Bt cotton．

The researchers say they do not believe that Bt cotton alone can solve all insect problems．Instead，they say farmers in China should consider it just one part of pest management systems．

44．What is Bt in this passage?

         A．It's a kind of hi-tech invention．      B．It's a natural bacterium．

         C．It's a kind of pest．                    D．It's a man-made pesticide．

45．Bt cotton has all the advantages EXCEPT that ________．

         A．it resists bollworms

         B．it does good to other crops growing around

         C．it reduces the use of insecticide

         D．it helps to develop new insects

46．The underlined word “ones” in the first paragraph refers to ________．

         A．bollworms             B．cotton crops          C．cotton seeds        D．pests

47．From the passage，we can infer ________．

         A．farmers around the world are now growing a large area of Bt cotton

         B．researchers are probably now searching for new ways to solve other cotton problems

         C．bollworms could not exist in Bt cotton any longer

         D．Chinese scientists found the way to grow Bt cotton

 

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科目：高中英語 來源：2011年黑龍江省高二下學期期末考試英語題 題型：單詞拼寫

1.A clone is an organism which is genetically i__________(同一的) to another one.

2. During the war, Germany o________(占領(lǐng)) many countries.

3. At one point, military commanders thought about a__________(放棄) the operation.

4. When he first arrived in the U.S, Yao was an i_________ hit among basketball fans nationwide.

5. In America, the development of social skills is c____________(認為) as important as the development of intellectual skills.

6. Would you please say something about the h__________(精彩生活) of your senior year?

7. The chair was i________ (打算) for you, but she took it away.

8.All the people in the world are looking forward to building a better society in h________(和諧) with nature.

9.I thought she had retire, but a__________(顯然) she hasn’t.

10.She was strongly r______________(推薦) for the post.

 

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科目：高中英語 來源：2010-2011學年重慶西南師大附中高第一次月考英語卷 題型：閱讀理解

Recently there was a major discovery in the scientific research — the mapping of all DNA in a human gene(基因) is complete. Couple of years ago, this seems an impossible task for scientist to accomplish. All this progress in science leads us to believe that the day, when the human being will be cloned, is not far away. Human cloning has always been a topic of argument, in terms of morality(道德) or religion.

Taking a look at why cloning might be beneficial, among many cases, it is arguable that parents who are known to be at risk of passing a genetic limitation to a child could make use of cloning. If the clone was free of genetic limitations, then the other clone would be as well. The latter could be inserted in the woman and allowed to ripen to term. Moreover, cloning would enable women, who can’t get pregnant, to have children of their own.

Cloning humans would also mean that organs could be cloned, so it would be a source of perfect transfer organs. This surely would be greatly beneficial to millions of unfortunate people around the world that are expected to lose their lives due to failure of single (or more) organ(s). It is also arguable that a ban on cloning may be unlawful and would rob people of the right to reproduce and limit the freedom of scientists.

Arguments against cloning are also on a perfectly practical side. Primarily, I believe that cloning would step in the normal “cycle” of life. There would be a large number of same genes, which reduce the chances of improvement, and, in turn, development — the fundamental reason how living things naturally adapt to the ever-changing environment. Life processes failing to do so might result in untimely disappearance. Furthermore, cloning would make the uniqueness that each one of us possesses disappear, thus leading to creation of genetically engineered groups of people for specific purposes, and chances are that those individuals would be regarded as “objects” rather than people in the society.

Scientists haven’t 100% guaranteed that the first cloned humans will be normal. Thus, this could result in introduction of additional limitations in the human “gene-pool”.

Regarding such arguable topics in “black or white” approach seems very innocent to me personally. We should rather try to look at all “shades” of it. I believe that cloning is only legal if its purpose is for cloning organs; not humans. Then we could regard this as for “saving life” instead of “creating life”. I believe cloning humans is morally and socially unacceptable.

1.Which of the following is true according to the passage?

A. Genetic limitations will be beneficial for some women.

B. A large number of genes will prevent us from developing.

C. First cloned humans might be normal according to scientists.

D. Forbidding cloning might limit the freedom of scientists.

2.What’s the author’s opinion on cloning?

A. It should be entirely banned.                         B. It is acceptable if it is used for cloning organs.

C. It will take away the right to reproduce.    D. It should be used in creating life.

3.Where can you read this article?

A. In a story book.                                                  B. In a magazine.

C. In a science fiction.                                           D. In a novel.

4.Which of the following shows the structure of the passage(1—6 refer to paragraph 1—6)?

 

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科目：高中英語 來源：2010-2011學年山西省高三上學期12月月考英語卷 題型：閱讀理解

Animals are more like us than we ever imagined．They feel pain, they experience stress, they show affection, excitement and love．All these findings have been made by scientists in recent years---and such results are beginning to change how we view animals.

Strangely enough, some of this research was sponsored by fast food companies like McDonald’s and KFC．Pressured by animal rights groups , these companies felt they had to fund scientists researching the emotional and mental states of animals.

McDonald’s, for instance, funded studies on pig behavior at Purdue University, Indiana．This research found that pigs seek affection and easily become depressed if left alone or prevented from playing with each other．If they become depressed, they soon become physically ill．Because of this, and other similar studies, the European Union has banned the use of isolating pig stalls from 2010．In Germany, the government is encouraging pig farmers to give each pig 20 seconds of human contact a day, and to provide them with toys to prevent them from fighting

Other scientists have shown that animals think and behave like humans．Koko, the 300-pound gorilla at the Gorilla Foundation in Northern California, for instance, has been taught sign language．Koko can now understand several thousand English words, more than many humans who speak English as a second language．On human IQ tests, she scores between 70 and 95.

Before such experiments, humans thought language skills were absent from the animal kingdom．Other myths are also being overturned, like the belief that animals lack self-awareness．Studies have also shown that animals mourn their dead, and that they play for pleasure.

These striking similarities between animal and human behavior have led some to ask a question: “If you believe in evolution, how can’t you believe that animals have feelings that human  beings have?”

Until recently, scientists believed that animals behaved by instinct and that what appeared to be learned behavior was merely genetically-programmed activity．But as Koko the Gorilla shows, this is not the case．In fact, learning is passed from parent to offspring far more often than not in the animal kingdom.

So what implications does this knowledge have for humans? Because of this, should we ban hunting and animal testing? Should we close zoos? Such questions are being raised by many academics and politicians．Harvard and 25 other American law schools have introduced courses on animal rights．Germany meanwhile, recently guaranteed animal rights in its constitution---the first country to do so.

1.McDonald’s and KFC give money to support scientist to do research on animals, because_____

A．they are international big companies.

B．they love animals.

C．they are pressured by animal right groups.

D．they earn a large amount of money and want to do some good deeds.

2.The research on pigs at Purdue University shows that______

A．pigs love being alone.

B．pigs easily become physically ill.

C．pigs need affection.

D．pigs don’t like to play with each other.

3.Which of the following statements is NOT true?

A．Animals behave by instinct.

B．Animals have self-awareness.

C．Animals have feelings and love.

D．Animals do not have language skills.

4.Should we ban hunting and animal testing?

A．Yes.

B．No

C．Not certain

D．Not mentioned

 

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