Can people change their skin color without suffering like pop king Michael Jackson? Perhaps yes. Scientists have found the gene that determines skin color.
The gene comes in two versions, one of which is found in 99 percent of Europeans. The other is found in 93 to 100 percent of Africans, researchers at Pennsylvania State University report in the latest issue of Science.
Scientists have changed the color of a dark-striped zebra-fish（斑马鱼） to uniform gold by inserting a version of the pigment (色素) gene into a young fish. As with humans, zebra-fish skin color is determined by pigment cells, which contain melanin (黑色素). The number, size and darkness of melanin per pigment cell determine skin color.
It appears that, like the golden zebra-fish, light-skinned Europeans also have a mutation (变异) in the gene for melanin production. This results in less pigmented skin.
However, Keith Cheng, leader of the research team, points out that the mutation is different in human and zebra-fish genes.
Humans acquired dark skin in Africa about 1.5 million years ago to protect bodies from ultra-violet rays of the sun (太阳光紫外线), which can cause skin cancer.
But when modern humans leave Africa to live in northern latitudes, they need more sunlight on their skin to produce vitamin D. So the related gene changes, according to Cheng.
Asians have the same version of the gene as Africans, so they probably acquired their light skin through the action of some other gene that affects skin color, said Cheng.
The new discovery could lead to medical treatments for skin cancer. It also could lead to research into ways to change skin color without damaging it like chemical treatment did on Michael Jackson.The passage mainly tells us that ________.
| A．people can not change their skin color without any pain |
| B．the new discovery could lead to research into ways to change skin color safely |
| C．pop king Michael Jackson often changed his skin color as he liked |
| D．scientists have found out that people’s skin color is determined by the gene |
It can be inferred from the passage that _____________.
| A．nowadays people who want to change their skin color have to suffer a lot from the damage caused by the chemical treatment |
| B．Europeans and Africans have the same gene |
| C．the new discovery could help to find medical treatments for skin cancer |
| D．there are two kinds of genes |
Scientists have done an experiment on a dark-striped zebra-fish in order to _____________.
| A．find the different genes of humans’ |
| B．prove the humans’ skin color is determined by the pigment gene |
| C．find out the reason why the Africans’ skin color is dark |
| D．find out the ways of changing people’s skin color |
The reason why Europeans are light-skinned is probably that _____________.
| A．they are born light-skinned people |
| B．light-skinned Europeans have mutation in the gene for melanin production |
| C．they have fewer activities outside |
| D．they pay much attention to protecting their skin |
The writer’s attitude towards the discovery is ______________.
| A．neutral | B．negative |
| C．positive | D．unconcerned |
第三部分：阅读理解（共20小题，每题2分，满分40分）
阅读下列短文，从每题所给的四个选项（A、B、C和D）中，选出最佳选项。
At the age of sixteen, I joined a volunteer group with my dad. I went on my first volunteer project in West Virginia. On the night we arrived, we discovered that “our family” was living in a trailer(拖车) that was in poor condition. A crew had been working on it for two weeks, but every time they finished one problem, another surfaced.
We decided the only reasonable solution was to build a new house – something unusual but necessary under these circumstances. The family was overjoyed with their new house that was twenty by thirty feet with three bedrooms, a bath and a kitchen.
On Tuesday of that week, while we ate lunch together, I asked the family’s three boys, Josh, Eric and Ryan, "What do you want for your new room?" Expecting toys and other gadgets that children usually ask for, we were surprised when Josh responded, "I just want a bed."
The boys had never slept in a bed! They were accustomed to plastic mats. That night we had a meeting and decided that beds would be the perfect gift. On Thursday night, a few adults in our group drove to the nearest city and bought beds and new bedding.
When we saw the delivery truck coming, we told the family about the surprise. We could hardly contain ourselves. It was like watching excited children on Christmas morning.
That afternoon, as we fitted the frames of the beds tog tether, Eric ran into the house to watch us. Too dirty to enter his room, he observed with wide-eyed enthusiasm from the doorway.
As my father slipped a pillowcase onto one of the pillows, Eric asked, "What is that?"
"A pillow," she replied.
"What do you do with it?" Eric continued to ask.
"When you go to sleep, you put your head on it,” I answered softly. Tears came to our eyes as she handed Eric the pillow.
"Oh . . . that's soft," he said, hugging it tightly.
Now, when my sister or I start to ask for something that seems urgent, my Dad gently asks, "Do you have a pillow?"
We know exactly what he means.
56．The writer’s first volunteer project was .
A．working on a poor trailer B．helping a poor family
C．donating beds and bedding D．dealing with a housing problem
57．On bearing Josh’s answer, the writer was shocked because .
A．the family lived in a trailer B．he expected to get some toys
C．he didn’t know what a bed was D．the boys had no bed to sleep in
58．From the passage, we can learn that Eric had never seen before.
A．a trailer B．a truck C．a pillow D．a house
59．By saying “Do you have a pillow?”, the writer’s father means that .
A．what they want to get may be unnecessary
B．they should not waste money on small things
C．they should do more volunteer work for the poor
D．what he will buy is not what they want but a pillow
D
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 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 foe 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 per cent．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．
67．Which of the following is true according to the passage?
A．Genetic limitation will be beneficial for some women．
B．A large number of genes will prevent us from developing．
C．Prohibition of cloning might limit the freedom of scientists．
D．First cloned humans might be normal according to scientists．
68．What's the author's opinion on cloning?
A．Cloning should be entirely banned．
B．Cloning should be used in creating life．
C．Cloning will take away the right to reproduce．
D．Cloning is acceptable if it is used for cloning organs．
69．Where can you read this article?
A．In a story book．
B．In a magazine．
C．In a science fiction．
D．In a brochure．
70．Which of the following shows the structure of the passage?
C
With alarming regularity, we read about oil tankers having accidents near land and the terrible consequences of the oil spills （泄露） on people, nature, and the environment．
Millions of dollars have been used in developing special chemicals to help dismiss the spills and to clean up the animals, beaches, and land spoiled by the oil．Unfortunately, when many of these chemicals are used, more damage is caused to the environment, especially to lives in the sea．
Of all of today's environmental disasters, an oil spill may actually be one of the least serious．Although oil is poisonous, it is a natural material．In the end, it breaks down naturally．There are, of course, long-term effects, but it is usually more serious in the short term．
Nature by itself works better than chemical materials, but when there is a spill we demand that governments act immediately with as much hi-tech knowledge as possible．In 1967 the tanker Torrey Canyon sank off the Scilly Isles near the coast of England and spilled 120,000 tones of oil into the ocean．If you go there today, you will find it hard to see any sign that it ever happened．
Governments seem to accept the risk of transporting millions of tons of oil by ship every day so that we can fill up our cars and drive around and cause even more environmental damage．Interestingly, the biggest companies in the world produce cars, and the next biggest supply the gasoline to make them run I
We should be thinking more about reducing our dependency on oil．Governments should be encouraging research into new technologies, such as cars run by solar power （太阳能） , electricity, hydrogen, and so on．Much of this research has, in the past, been held back by the oil, gas, and coal．
If the world's millions of cars were 10% more efficient （高效的）—and the industry could easily produce cars at least twice as efficient ?we would need many fewer tankers crossing the oceans each year．If this happened, the risks of oil spills would be reduced, and the air we breathe would be cleaner and fresher, too．
63．What is the passage mainly talking about?
A．Oil spills pollution． B．What oil pollution is．
C．Oil tanker accidents. D．How to reduce oil pollution.
64．How does the author support the idea that oil spills are not as serious as people believe?
A．By giving a description． B．By making an argument．
C．By giving an example． D．By drawing a diagram．
65．What does the underlined word "risk" in Paragraph 5 refer to?
A．Transportation depending more on oil．
B．Poisonous oil breaking down naturally．
C．Millions of tons of oil spilling into the sea．
D．More environmental damage being caused．
66．Which suggestion, is made for reducing oil tank accidents according to the passage?
A．We should build safer tankers in the near future．
B．We should develop new technologies to cut oil use．
C．Tankers should not be allowed to sail near the coastlines．
D．Countries should build more oil pipelines under the sea．
B
Volunteers, as an essential part of a successful world exposition, are a major channel for the public to participate in, serve and share the world exposition and a means to showcase the image of the host country and city. The following information is about the volunteer for the World Exposition 2010 Shanghai China．
I．Basic Requirements for Volunteers
● Be willing to participate in voluntary services of Expo 2010;
● Age limit: Expo Site volunteers must be born before April 30,
1992 and Expo City Voluntary Service Station volunteers before
April 30, 1994;
● Obey the laws and regulations of the PRC;
● Be able to participate in training and relevant activities before the opening of Expo 2010;
● Possess necessary knowledge and skills needed by the position;
● Be in good health to meet the requirements of corresponding voluntary positions．
II．Further Information for Volunteers
● Source
Residents of Chinese mainland, Hong Kong, Macau and Taiwan, as well as overseas Chinese, and foreigners can all apply to be the volunteers．
● Signup methods
Applicants may log in onto the official websites for online signup．They may also consult or connect with the Expo Volunteer Stations．
● Time
May 1 - December 31, 2009
Ⅲ．Volunteer Training
Volunteer training includes general training, special training and position training．General training is carried out through internet, while special training and position training are provided through classroom lectures and field practice．
IV．Volunteer Types
● Expo Site volunteers refer to those offering voluntary services to visitors and the Organizer in the Expo Site, mainly including information, visitor flow management, reception, translation and interpretation, assistance for the disabled, and assistance in media service, event and conference organization and．volunteer management．
● Information booth volunteers are stationed in the Expo's information booths at key transportation centers, commercial outlets, tourist attractions, restaurants, hotels and cultural event places outside the Expo Site．They offer services including information, translation, interpretation and even first aid．
60．If you were born in April 1993, where can you be a volunteer?
A．In the Expo City． B．In the host country．
C．In the Expo Site． D．In Chinese mainland
61．Which of the training will be done on the Internet?
A．Position training． B．General training．
C．Classroom training． D．Special training．
62．Which of the following service is offered by information booth volunteers?
A．Visitor flow management． B．Helping the disabled
C．Assistance in media service． D．Emergency First aid．
第三部分：阅读理解（共两节，40 分）
第一节：（共15小题；每小题2分，共30分）
阅读下列短文，从每题所给的A、B、C、D四个选项中，选出最佳选项，并在答题卡上将该项涂黑。
A
Shopping in the United States changes a lot．About ninety years ago most people shopped in small stores that were owned by one person or a family．Women went from the bakery to the butcher's to the grocer and on to the fruit and vegetable seller in order to get their food for the week．
Then about sixty years ago, supermarkets were born．In a supermarket, people could get all the different kinds of food they needed without going to different stores．
The next big change in shopping in the United States was the shopping mall．A shopping mall is a group of stores under one roof．Because malls allowed people to shop without worrying about the weather, they soon became very popular．The mall became a place for people to socialize in addition to shopping．If you walk through a mall, you will see older people sitting, chatting and drinking coffee．Malls are places for teenagers to hang out．Many teens will often just "go to the mall" and spend time with their friends．
The recent change in American shopping was the superstore．Large chain stores such as Wal-Mart, Office Depot and Toys "R" Us have been built all across the United States．Because they are so large, they can buy goods at a great discount and sell them much cheaper than smaller stores．
Sometimes, when they are built near small towns, many of the small town stores have to close．They just cannot compete with their giant neighbors．
And now, online shopping is becoming more and more popular all over the States．People are too busy to go to the physical stores, so they go shopping over the Internet．Online shopping has lots of advantages．For instance, online stores are usually available 24 hours a day．Searching or browsing online shops can be faster than browsing the physical stores．While, online shopping also has its disadvantages．People are at higher risk of being cheated on the part of the merchant than in a physical store．And privacy of personal information may be let out．
56．Which of the following shows the right order of shopping development in the United States?
①small stores ②superstores ③shopping malls ④shopping online
⑤supermarkets
A．①②③④⑤ B．①⑤②③④
C．①⑤③②④ D．②③④①⑤
57．Which is the place for people to spend time with others according to the passage?
A．Shopping malls． B．Small stores．
C．Supermarkets． D．Superstores．
58．Why can the superstores sell products at much lower prices?
A．Because they are built near small towns．
B．Because they are across the United States．
C．Because they sell all kinds of products people need．
D．Because they can buy goods at a reduction in the price．
59．What's the disadvantage of online shopping according to the passage?
A．Wasting time． B．Leaking personal information．
C．Fixed prices． D．No chance to do physical activities
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