Can people change their skin colour without suffering like pop king Michael Jackson? Perhaps yes.
Scientists have found the gene that determines skin colour.
The gene comes in two versions, one of which is found in 99 per cent of Europeans. The other is
found in 93 to 100 per cent of Africans, researchers at Pennsylvania State University report in the latest
issue of Science.
Scientists have changed the colour of a dark-striped zebrafish to uniform gold by inserting a version
of the pigment (色素) gene into a young fish. As with humans,zebrafish skin colour is determined by
pigment cells, which contain melanosomes (黑色素). The number, size and darkness of melanosomes
per pigment cell determines skin colour.
It appears that, like the golden zebrafish,light-skinned Europeans also have a mutation (变异) in the
gene for melanosome 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 zebrafish genes.
Humans acquired dark skin in Africa about l.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 verslon of the gene as Africans, so they probably acquired their light skin through
the action of some other gene that affects skin colour, said Cheng.
The new discovery could lead to medical treatments for skin cancer. It also could lead to research into
ways to change skin colour without damaging it like chemical treatment did on Michael Jackson.
科目：高中英语 来源：陕西省2010届高三适应性训练（英语） 题型：阅读理解
第二部分：阅读理解（共20 小题。第一节共15 小题，每题2分；第二节共5 题，每题2分；共40 分）
阅读下列短文，从每题所给的四个选项 A．B．C．D中选出最佳选项。
A
Unnoticed and unappreciated for five decades，a large female turtle （龟）with a stained（彩色的），leathery（粗而硬的） shell is now a precious commodity（物品）in Changsha’s old zoo．She is fed on a special diet of raw meat．Her small pool has been covered with glass which can defend it from bullets．A special camera monitors her movements．A guard is posted at night．
The purpose is simple：the turtle must not die．
Earlier this year，scientists concluded that she was the planet’s last known female Yangtze giant soft shell turtle．She is about 80 years old and weighs almost 90 pounds．
As it happens，the planet also has only one known male．He lives at a zoo the city of Suzhou．He is 100 years old and weighs about 200 pounds．They are the last hope of saving a species believed to be the largest freshwater turtles in the world．
“It’s a very dangerous situation,” said Peter Pritchard, a famous turtle expert in the United States，who has helped try to save the species．、
For many Chinese people，the turtle is the symbol of health and long life，but the last two Yangtze giant soft-shell creatures show the threatened state of wildlife and biodiversity（生物多样性）in China．Pollution, hunting and over development are destroying natural habitats，and also endangering the plant and the animal population．
China contains some of the world’s richest treasures of biodiversity, yet the latest major survey of plants and animals shows a discouraging picture．Nearly 40 percent of all mammal species in China are now endangered, Scientists say．For plants，the situation is worse；70 percent of all nonflowering plant species and 86 percent of flowering species are considered threatened．
46．Why is the turtle in Changsha specially cared?
A．She has been unnoticed and unappreiated five decades．
B．She can be sold at a high price．
C．She is the planet’s last known female Yangtze giant soft-shell turtle．
D．She is old and heavy．
47．Which of the following statements is TRUE according to the text?
A．The turtle in Changsha is precious because it is the symbol of health and long life．
B．Peter Pritchard believes the female turtle is the largest freshwater turtle in the world．
C．The female turtle is in a dangerous situation where she may be killed．
D．The female turtle in Changsha and the male turtle in Suzhou are the last hope of saving the largest freshwater turtle species in the world．
48．According to the text ________in China．
A．there are the richest species of living things
B．wild plants and animals are becoming fewer
C．turtles are specially protected
D．the situation of plants is better than that of mammal species
49．The last paragraph proves the threatened state of wildlife and biodiversity in China by__________ ．
A．facts and numbers B．Peter Pritchard’S words
C．teaching theory D．telling a story
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科目：高中英语 来源：湖北省20092010学年高一下学期期末考试试题（英语） 题型：阅读理解
第三部分：阅读理解（共20小题：每小题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，并在答题卡上将该项涂黑。
Football, to me, is more than just a game. I have probably learned more than valuable lessons from it than from school.
When I joined the team freshman year, I didn’t realize what I was getting into. Even though I had been playing since fourth grade and knew it was hard work, nothing would prepare me for the effort I would put into football that year. We worked all summer in the weight room and ran on the track to get in physical and mental shape before the season.
See, football is more of a mental sport than anything else, so running on the track wasn’t only about getting in shape. We would push our minds by running as hard as we could even if we felt like we were going to pass out. At the beginning, I was immature (幼稚的) and only thought of myself, sometimes even giving up when I was tired or hurting. Then after the third game I had a season-ending injury. Imagine working all summer and then only being able to play three games! I needed an operation on my arm and at least five months to recover.
After freshman year I decided that I would always give my best effort. Playing football in the college has taught me so much more than just what my tasks are on a particular play or how to block. I have learned to think about others first, and realized how important working hard is. Being with all my friends, even sweating and bleeding with them, really made us unite as a group of hard-working young men, who will succeed in life.
51．What is the text mainly about?
A．How the author dislikes the game of football.
B．When the author began to play football.
C．How the author has changed his attitude to football.
D．What sport the author likes best.
52．The author thinks football is ________.
A．just a game B．of a mental sport
C．hard to be out-of-date D．not worth his effort
53．From the text we can infer ________.
A．the author joined the football team with a clear aim.
B．football only brought the author certain tasks
C．the author worked all summer to get ready for the season.
D．the author never lost heart when he met with difficulties.
54．In the third paragraph, the phrase“getting in shape”probably means ________.
A．becoming physically fit B．designing the playground
C．losing weight D．measuring the track
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科目：高中英语 来源：湖北省2009-2010学年度高一下学期期中考试试题（英语） 题型：阅读理解
.
第三部分：阅读理解（共20小题；每小题2分，满分40分）
阅读下面文章，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。
It was the afternoon of December 24, the day before Christmas, and as the newest doctor in our office, I had to work. The only thing that brightened my day was the beautifully decorated Christmas tree in our waiting room and a gift sent to me by a fellow I was dating(约会)—a dozen long-stemmed red roses.
As I was cleaning my office, I was told a lady urgently needed to speak with me. As I stepped out, I noticed a young, tired-looking woman with a baby in her arms. Nervously, she explained that her husband—a prisoner in a nearby prison—was my next patient. She told me she wasn’t allowed to visit her husband in prison and that he had never seen his son. Her request was for me to let the boy’s father sit in the waiting room with her as long as possible before I called him for his appointment（约见）. Since my schedule wasn’t full, I agreed. After all, it was Christmas Eve.
A short time later, her husband arrived—with chains on his feet and hands, and two armed guards as bodyguards. The woman’s tired face lit up like our little Christmas tree when her husband took a seat beside her. I kept glancing out to watch them laugh, cry and share their child. After almost an hour, I called the prisoner back to my office. The patient seemed like a gentle and modest man. I wondered what he possibly could have done to be held under such conditions. I tried to make him as comfortable as possible.
At the end of the appointment, I wished him a Merry Christmas—a difficult thing to say to a man headed back to prison. He smiled and thanked me. He also said he felt saddened by the fact that he hadn’t been able to get his wife anything for Christmas. On hearing this, I was inspired with a wonderful idea.
I’ll never forget the look on both their faces as the prisoner gave his wife the beautiful, long-stemmed roses. I’m not sure who experienced the most joy—the husband in giving, the wife in receiving, or myself in having the opportunity to share in this special moment.
51.What can be inferred from the first paragraph?
A. The writer was a newcomer to her office.
B. A fellow sent her a dozen red roses as Christmas present.
C. She was in low spirits because she had to work before Christmas.
D. She was at work with a light heart.
52. The young woman came to the writer’s office for the purpose of .
A. having her baby examined
B. giving her husband a chance to make his escape
C. having her husband examined
D. getting a chance for her family to get together
53.The underlined part in Paragraph 3 most probably means “ ”.
A. to be sent to hospital B. to be separated from his family
C. to be comfortable D. to become a prisoner
54. What does the writer learn from the story?
A. The wife experienced the most joy in receiving.
B. An act of kindness can mean a lot.
C. The prisoner was treated with mercy.
D. Whoever breaks the law should be punished.
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科目：高中英语 来源：河北省2009-2010学年度高一下学期期中考试英语试题 题型：阅读理解
第二部分阅读理解（共25小题。第一节每小题2分，第二节每小题1分；满分45分）
阅读下例短文，从每题所给的四个选项中，选出最佳选项（共20小题；每小题2分，满分40分）
Once a group of 17-year-old schoolboys decided to break the world basketball marathon（马拉松）record. They wanted to play for 90 hours and add 6 hours to the record. Each team had 9 players, with 5 at a time. The boys decided each person would play 21.5 hours and then rest for 2 hours. Then they started at 6 o’clock in the evening.
The first night was very hard for the players. When it was their turn to rest, they were too excited to fall asleep at once. After sleeping for a short time, they had to play again. On the second night,they fell asleep as soon as they stopped, Some of them had trouble with their feet and hands, but the only serious problem was a psychological（心理学的）one. Each boy was thinking: Why am I doing this? How can I play any longer? After the third night, the players knew they could finish the 90 hours. The basketball on the fourth night was very slow. But in the final hours, the players got better. For the last few minutes, the players looked as fresh as when they started. How happy everyone was!
41．Before this basketball marathon, the world record was .
A．84 hours B．86 hours C．90 hours D．96 hours
42．The first night was hard for the players because_______.
A．they were too excited B．they only slept for a short time
C．no one watched them play D．it was very long
43．“…the players looked as fresh as when they started.”Here “fresh”means_______.
A．不熟练的 B．兴奋不己的 C．精神饱满的 D．伤痕累累的
44．Which of the following is not true.
A．Some of the boys were hurt when they played
B．It was hard for the players to fall asleep at night
C．The boys started playing at 6 o’clock in the evening
D．In the end, all the boys felt happy
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科目：高中英语 来源：新疆农七师高级中学2009-2010学年度高一下学期第二阶段考试英语试题 题型：阅读理解
第二部分：（共两节，满分45分）：
第一节：阅读理解 （共20小题； 每小题2分，满分40分）
Every country has its heroes. The heroes are the people the nation and especially the young people admire. If you get a list of the heroes of a nation, it will tell you the potential（潜势）of that nation.
If today in America, you ask the high school students to list their heroes, their choice would probably fall into three groups. The first group of heroes would be the rock stars —the people connected with rock music. There is no doubt that such people do have talent but one wonders if one should hold up rock stars as a model (推举…为榜样). The rock stars too often are involved with drugs and their personal life is not all that good. The rock stars are rich and wear the latest fashion styles. However, one should seek more in a hero than such things as money and good clothes.
A second type of hero for the American youth is the sports star. Again you have a person who has a great ability in one area — SPORTS. However, too often the personal life of the sports star is a bit of a mess. Too frequently drugs and drinking are a part of life of the sports star.
A third type of hero is the TV or movie star. This person may have lots of acting talent and is quite handsome. However, the personal life of too many actors is quite sad and they should not be held up as a model for young people.
Today, the rock star, the athlete and the actor all have become the models of the youth in America. Really, do you hear a young person say that his hero is a doctor, a teacher, or a scientist? These people are not rich and do not wear fashionable clothes. However, they are talented people who work hard to make the world a better place for everyone.
What is really sad is that the young try to imitate their heroes. They like to wear the same clothes and follow their styles. If the heroes of today for the American youngsters are only rock stars, athletes and actors, the future does not look too bright.
1. The hero discussed in this article means a person ______.
A. who has done something brave B. who plays an important role in a play
C. whom people greatly admire D. who rides the waves and moves with the tides
2. What is true of the groups mentioned in this article?
A. They are not fright but are good-looking.
B. They are rich but are strict with themselves.
C. They are talented in some area but lead an indecent life.
D. They are perfect in every way.
3. American young people will not admire ______.
A. a university professor B. a popular singer C. a football player D. a film actress
4. According to the writer, people should hold up as their model those______.
A. who are rich and wear the latest fashion clothes B. whose personal life is good
C. who can express people’s feelings D. who work in the interests (利益) of the people
5. What is the writer’s attitude towards American youth’s admiration for their heroes?
A. He is understanding. B. He is critical. C. He is angry. D. He is uninterested.
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