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 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 color of a dark-striped zebrafish（斑马鱼） to uniform gold by inserting a version of the pigment (色素) gene into a young fish. As with humans, zebrafish 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 zebrafish, 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 zebrafish 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.
【小题1】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 |
| 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 |
| 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 |
| 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 |
| A．neutral | B．negative | C．positive | D．unconcerned |
阅读快车系列答案科目：高中英语 来源： 题型：阅读理解
Unlike traditional commercials, Public Service Advertisements（PSA）are primarily designed to inform and educate rather than sell a product or service. The goal of a PSA is not to make a big sale, but rather to change public opinion and raise awareness for a problem.
Smokey Bear has been a recognized symbol of the protection of America’s forests from fire. It is created to educate the public about the dangers of wildfires. Smokey Bear was started in 1944 with the slogan, “Smokey Bear Says—Care will prevent 9 out of 10 forest fires”. Smokey Bear’s later slogan, “Remember! Only You Can Prevent Forest Fires”, was created in 1947 by the Advertising Council in America. In April 2001, the message was changed to “Only You Can Prevent Wildfires”.
The wildfire prevention campaign with Smokey Bear is one of the longest and most successful campaigns in advertising history. The Advertising Council often was in partnership with other organizations and groups to create various advertising for Smokey Bear since 1944.
The Advertising Council teamed with Walt Disney Company to create a series of PSAs. The ads feature（以···为形象）characters form the classic film Sleeping Beauty and aim to reach parents and children. The lovely Bambi also appeared in the advertisements. Mickey Mouse is much more popular throughout the country.
Those PSAs, which appear on television, on the radio, in the newspaper and on the website continue to remind Americans about the importance of wildfire prevention have helped to reduce the number of acres burned annually by wildfires. According to recent survey, Smokey Bear and his famous words of wisdom “Only You Can Prevent Wildfires” are recalled by 3 out of 4 adults.
In addition to the PSA campaign, Smokey Bear has his own U.S. postage stamp and website for more information about wildfire prevention. From the website, you can also learn all about wildfires and how we can protect our forests.
【小题1】PSA are primarily designed to .
| A．educate the public | B．change people’s status |
| C．discuss a problem | D．sell products or services |
| A．It is one recognized symbols of Walt Disney cartoons. |
| B．It firstly appeared in America in 1944 with no slogan. |
| C．It is created to warn Americans of the dangers of wildfires. |
| D．Its slogan changes every three years. |
| A．By summing up. | B．By giving examples. |
| C．By comparison. | D．By asking questions. |
| A．helps a lot to reduce wildfires in America |
| B．isn’t popular among the American pupils |
| C．has set up its own website to advertise products |
| D．becomes the symbol of the Advertising Council |
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科目：高中英语 来源： 题型：阅读理解
Scientists in Mexico have just begun a new study of one of the world’s biggest pyramids: the Pyramid of the Sun, north of Mexico City. They’re putting lots of small, high-tech machines under the pyramid to try to unlock some of its secrets. For thousands of years, people have tried to uncover the secrets of the pyramids.
The people who built the pyramids made lots of secret doors and rooms to stop robbers from finding the treasures inside. However, there always have been some smart thieves in history. Now, almost all of Egypt’s pyramids have been robbed, including the Great Pyramid of Khufu, which is the largest pyramid in the world. It is the only one of the ancient wonders of the world that is still standing.
In AD 820, an Arab king named Abdullah AL Manum got a group of workers to dig their way into the Great Pyramid and have a look. Inside the pyramid, they found three rooms—the Queen’s Chamber, the Grand Gallery and the King’s Chamber. But to their surprise, the men didn’t find the treasures they wanted. The Queen’s and King’s Chambers were both empty! Where were the King’s mummy and his treasures? Had someone already taken them away? The huge stone doors at the pyramid’s entrance were still closed when AL Manum’s men went inside. How had the thieves got in and out?
Since then, many people have gone inside the Great Pyramid to have a look or to try to take things. But still, no other chambers or walkways have been found.
In 2002, an American team made the most recent visit to the Great Pyramid. Scientists sent a robot into the pyramid, but they only found a mysterious locked stone door.
【小题1】 The first two paragraphs were written to show that ____.
| A．ancient Egyptian emperors were cruel |
| B．the Pyramid of the Sun is an unusual historic building |
| C．construction workers led a hard life in ancient Egypt |
| D．the secrets of the pyramids remain to be uncovered |
| A．To try to unlock some of its secrets |
| B．To stop robbers from finding the treasures inside |
| C．To refuse some visitors all over the world into it |
| D．To tell the truth to the people in the future |
| A．It is the largest pyramid in the world. |
| B．It is the only one of the ancient wonders that is still standing. |
| C．Abdullah AL Manum took the King’s mummy and his treasures away |
| D．Scientists found a mysterious locked stone door to the Great Pyramid |
| A．The Pyramid of the Sun |
| B．The Great Pyramid of Khufu |
| C．A Mysterious Locked Stone Door |
| D．Unlocking the Doors of History of the Pyramid |
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科目：高中英语 来源： 题型：阅读理解
Plastic is everywhere because plastic is an extremely useful material. It is cheap, strong and lightweight. What’s more, it can take on nearly any form or shape, from soft and stretchy (有弹性的) to hard and glasslike.
Plastic, however, is far from perfect. It may even be bad for us. Studies now suggest that poisonous chemicals can get out of some types of plastic, get into our bodies, and cause a variety of health problems, including cancer, birth defects and attention deficit hyperactivity disorder (注意缺陷障碍).
Two types of chemicals in particular have raised special concern lately. They are called phthalates (邻苯二甲酸盐) and Bisphenol-A (二酚基丙烷), BPA for short. Not all plastic products contain them. But the ones that do are surrounded by controversy (争议). That’s because experts disagree on how dangerous these chemicals are.
Plastic is a single word, but plastic isn’t just one thing. What all plastics share in common are plasticizers -- special chemicals that allow the material to be changed into nearly any shape or texture. Plasticizers (塑化剂) are added to plastic during the manufacturing process.
Phthalates and BPA are two types of plasticizers that work in different ways. Phthalates add softness to things like shampoo bottles, raincoats and rubber. They are also used in perfumes and makeup. BPA, on the other hand, gives a hard, clear, almost glasslike feel to products such as infant bottles. BPA also appears in food and soda cans, DVDs and other unexpected places.
How do these chemicals get into us? When plastic is heated in the microwave or dishwasher, chewed on or scratched, the chemicals can seep (渗透) out of the plastic. Even though we can’t see them, we eat them, drink them and breathe them in.
Scientists and parents are especially worried about young children, who tend to chew on everything, including plastic. Dozens of countries, including the European Union, Japan, Canada and Mexico have already banned phthalates from products made for children younger than three. California and Washington have done the same. And a number of other states are considering similar rules. As for BPA, Canada became the first country to ban the chemical from baby bottles. A dozen states are considering it.
【小题1】What can we know about the plastic from the first paragraph?
| A．Its characters and effects. | B．Its wide use and bad points. |
| C．Its importance and chemicals. | D．Its popularity and advantages. |
| A．A soft plastic cup. | B．A pencil eraser. |
| C．A baby milk bottle. | D．A new perfume. |
| A．through mouth or nose | B．through blood transfusion |
| C．by feeling plastic products | D．by heating in the microwave |
| A．A new ban on plastic products. | B．Problems caused by the plastic. |
| C．Good points of the plastic. | D．The use of plasticizers. |
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科目：高中英语 来源： 题型：阅读理解
When Geoff Marcy was 14, his parents bought him a telescope. Every night, he would go onto the roof outside his window to see the wonders of the sky.
“What excited me most was whether there were planets in other solar systems where life might exist,” he says. “I decided to try to find planets orbiting other stars like our Sun.”
And he did. “My fellow researcher, Paul Butler, and I found our first planet in 1995,” Dr. Marcy says. “We worked for ten years without finding anything! But we stuck with it and our patience paid off.”
Since then, the two scientists have discovered 65 of the more than 100 planets found orbiting other stars. Dr. Marcy and Dr. Butler also spotted the first “family” of three planets. In June 2002 they announced another discovery: a Jupiter-like planet orbiting star 55Cancri.
At first, the two researchers found only planets that orbit close to stars. Recently, the scientists found planets farther out. The planet orbiting 55Cancri is a major breakthrough: it is the first sighting of a large gas planet about same distance from the star as Jupiter is from the Sun.
Why is this important ? Scientists think that life on Earth may exist because of two special features in our solar system. The first is Jupiter.
“Because it’s so big, Jupiter pulls comets and asteroids(小行星), or they all come and hit the Earth.” Dr. Marcy explains. “Without Jupiter , life on Earth would likely have been destroyed.”
A second feature is that Earth is a rocky planet where liquid water, which is necessary for life , can exist. Unlike gas planets, rocky planets like Earth have surfaces where water can gather in pools and seas, which may support life. A huge space exists between the Jupiter-like planet and two other planets that lie close to 55Cancri. Is there an Earth-like planet in the space, too small for us to notice? If so, says Dr. Marcy, “We would have two striking similarities to our solar system: a Jupiter-like planet and an Earth-like planet. And there may be life!”
【小题1】What can we learn about Dr. Marcy from the passage?
| A．He is fond of watching Jupiter. |
| B．He is from a scientist family. |
| C．He dislikes working with Paul Butler. |
| D．He is interested in finding life in outer space. |
| A．The planet is not as protective as Jupiter. |
| B．The planet is close to star 55Cancri. |
| C．The planet proves to be a gas planet. |
| D．The planet is as large as Jupiter. |
| A．1995 | B．1985 | C．2002 | D．1981 |
| A．he has found the system similar to the solar system. |
| B．he has discovered an Earth-like planet there. |
| C．he has discovered a rocky planet there. |
| D．he has found signs of life in the system |
| A．they felt discouraged | B．they carried on with it |
| C．they failed in their attempt | D．they made some progress |
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科目：高中英语 来源： 题型：阅读理解
Satellites are an important part of our ordinary lives．For example, the information for weather forecasts is sent by satellite．Some satellites have cameras which take photographs of the Earth to show how clouds are moving．Satellites are also used to connect our international phone calls．
Computer connections of the World Wide Web and Internet also use satellites. Many of our TV programs come to US through satellites．Airplane pilots also sometimes use a satellite to help them find their exact location．
We use satellites to send television pictures from one part of the world to another．They are usually 35，880 kilometers above the equator．Sometimes we can see a satellite in the sky and it seems to stay in the same place．This is because it is moving around the world at 11，000 kilometers an hour—exactly the same speed that the earth rotates．A satellite must orbit the Earth with its antennae(天线)facing the earth．Sometimes, it moves away from its orbit，So there are little rockets on it which are used to put the satellite back in the right position．This usually happens about every five or six days．
Space is not empty! Every week, more and more satellites are sent into space to orbit the Earth．A satellite usually works for about 10-12 years．Satellites which are broken are sometimes repaired by astronauts or sometimes brought back to Earth to be repaired．Often，very old or broken satellites are left in space to orbit the Earth for a very long time．This is very serious because some satellites use nuclear power and they can crash into each other．
【小题1】Which of the following is NOT done by satellites according to the passage?
| A．Sending information for weather forecast |
| B．Taking photographs of the Earth |
| C．Sending TV pictures |
| D．Providing food for airplane pilots |
| A．35,880 kilometers per hour． | B．335,880 kilometers per hour |
| C．11,000 kilometers per hour． | D．110,000 kilometers per hour |
| A．In order to take photographs |
| B．In order to stay in a certain position in the orbit |
| C．In order to move away from its orbit |
| D．In order to send television pictures． |
| A．A satellite |
| B．A little rocket |
| C．A satellite seems to stay in the same place in the sky |
| D．The satellite puts the rockets in the right position． |
| A．A satellite usually works for about 10-12 years． |
| B．Every time a satellite gets broken，it is brought back to the Earth to be repaired． |
| C．A broken satellite is never left in space |
| D．They often crash into each other． |
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科目：高中英语 来源： 题型：阅读理解
While nature lovers across the world wish all humans to realize the significance of their natural surroundings ,many Australians are turning caring for the environment into a way of life.
Julie Astonis ,an Australian housewife in Brisbane is one such example, Even though autumn is approaching Australia’s Brisbane in April, one can still watch colorful blooming （盛开的）flowers in Julie’s little garden, as she tells that in her community, “Each of us has a beautiful yard, The whole community, from children to elderly people, takes care of the environment as if they are taking care of their own garden.”
“Gardening is the most popular club in our community,”she says, “A lot of retired people don’t just regularly organize gardening lectures, but also personally visit families in the community to provide gardening training , So you can see that flowers continue to bols-som in our gardens throughout the year.”
Talking about her people’s sense of care for the environment, Julie says when people in the community take along their dog, they always carry a garbage bag to deal with the dog’s waste, “In our community ,you will never experience the embarrassment of stepping on the dirty waste while you are walking on the grass,”says Julie with a smile,“Taking care of the dog’s waste can also help to develop children’s sense of responsibility!”
As to protecting water resources , the Australian government has made strict rules for families, Julie says, “We certainly would not use tap water to water the flowers!”She ways almost every family in her community has a huge tank used to store rainwater, which is later used as the resource of all outdoor water use, connect the water tank with their toilets.
【小题1】From the first three paragraphs we learn that .
| A．gardening is popular in most part of Australia |
| B．April is a great time for people to enjoy flowers |
| C．it’s not easy to keep a garden without proper training |
| D．Julie’s community has a deep sense of caring for nature |
| A．She takes pride in her community. |
| B．She once stepped on a dog’s waste. |
| C．She is quite in favor of raising a dog. |
| D．She finds it embarrassing to walk on the grass. |
| A．rainwater is not the best resource |
| B．her community owns a public tank |
| C．her community makes full use of resources |
| D．it is not necessary to water flowers very often |
| A．Two | B．Three | C．Four | D．Five |
| A．Love nature, the Australian way | B．How Australians save resources |
| C．How Australians lead their life | D．Protect nature, a must of life |
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科目：高中英语 来源： 题型：阅读理解
In a recent study, researchers have estimated the energy required to produce bottled water, including the energy required to manufacture plastic, make the plastic into bottles, process the water, fill and seal the bottles, transport the bottles, and chill the bottles for use. Combining all the energy input totals for treatment and distribution, researchers found that producing bottled water requires between 5.6 and 10.2 million joules(焦耳) of energy per liter, depending on transportation factors. That's up to 2, 000 times the energy required to produce tap water.
To break down the energy requirements, researchers found that producing the plastic bottles and transporting the bottles greatly dominated(控制) the energy input. Although some companies are experimenting with producing lightweight bottles or using recycled materials, the researchers calculated that the manufacturing cost is about 4 million joules of energy per plastic bottle weighing 38 grams, and the cap weighing 2 grams.
“Our previous work had suggested that bottled water production was an energy intensive process, but we were surprised to see the results, ” the researchers said.
Transportation costs vary depending on the distance and mode of transport and both factors depend on the type of bottled water. There are two main kinds of bottled water in the US:” spring water” which comes from an underground spring and “purified water”,which is city tap water that has received further treatment. For purified water distributed locally by truck within Los Angeles, the total transportation energy is about 1.4 million joules per liter. In the second situation, spring water shipped from Fiji (such as Fiji Spring Water) across the Pacific to Los Angeles, and then delivered locally by truck requires about 4 million joules per liter for transportation. For the spring water, the transportation energy equaled (in the case of Fiji) the energy required to produce the bottle.
With this data, the researchers hope that future studies will have the ability to make specific estimates for different situations, and possibly find ways to cut energy costs.
【小题1】From the first Paragraph we can know that the energy required to ______.
| A．produce bottled water includes the energy required to drink it |
| B．distribute bottled water includes the energy for producing the bottles |
| C．distribute bottled water is much smaller than the energy for treating it |
| D．produce bottled water is much smaller than the energy for producing tap water |
| A．to fill tap water into the plastic bottles directly |
| B．to replace the plastic bottles with metal containers |
| C．to produce lightweight bottles with recycled materials |
| D．to use bicycles to transport and deliver bottled water locally |
| A．Treatment of bottled water needs no energy input at all. |
| B．Bottled water production is an energy intensive process. |
| C．Transportation of bottled water takes up the most energy input. |
| D．Production of the plastic bottles greatly dominated the energy input. |
| A．there are two main kinds of bottled water in the US |
| B．world consumption of bottled water has been increasing |
| C．transportation costs have something to do with the mode of transport |
| D．bottled water produced in Spring is more expensive than purified water |
| A．To help consumers themselves make more environmentally sustainable choices. |
| B．To advise the government to take severe measures to stop producing bottled water. |
| C．To urge the consumers to drink tap water instead of bottled water for the sake of the earth. |
| D．To try the best to find ways to produce bottled water cheaply and quickly for the companies. |
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科目：高中英语 来源： 题型：阅读理解
Monitoring global warming usually requires a Ph. D. and enough maths to glaze your eyes. But that Francisco Lopez and Ruby Nostrant track（记录）what climate change is doing to five different plants in Tucson, Arizona and they are only in the second grade.
“We are collecting data because the weather is changing and the plants are blooming,” Ruby explained.
Scores of other students at Borton Primary Magnet School and Sunnyside High School in Tucson are heading outdoors to be part of a new scientific push to figure out how the biological timing of the earth is changing. It’s a research project that the average person, even a kindergartner, can join in.
The National Phenology（生物气候学）Network is calling on volunteers to help track early spring blooms and eventually changes in animals caused by global warming. It’s called Project Budburst. When it was first open to the public last year, thousands of people participated in 26 states.
“All people can contribute to it by tracking the timing of flowering events or leaf-out events for plants and animals in their backyard,” said Phenology Network director Jake Weltzin. He calls the volunteers “citizen-scientists.”
The idea is that tracking flowers blooming—especially lilacs（丁香）; which everyday people have helped track for decades—is fairly simple. The Website http://www.Windows.ucar.edu/ citizen_science/budburst/index.html gives directions on what to look for in different parts of the country.
University of Maryland professor David Inouye said it’s so easy to figure out what’s blooming that a lack of special knowledge isn’t a problem.
University of Arizona ecology graduate student Lisa Benton coordinated（协调）the Tucson high school students as they looked at plants five minutes from their high school. Each student has specific guidelines and she’s been happy so far with the data she is getting. For his part, second-grader Francisco said he had fun helping out.
“I like going out in the desert,” he said. “I want to be an Einstein.”
【小题1】Francisco Lopez and Ruby Nostrant are monitoring global warming by __________.
| A．watching early spring blooms and changes in animals |
| B．studying the biological timing of earth |
| C．collecting data of the local weather |
| D．tracking the early spring blooms of some local plants |
| A．ecology college graduates | B．high school students |
| C．common people | D．experts |
| A．the study carried out by students is convincing |
| B．the students still need special training to study climate change |
| C．it is difficult to study climate change |
| D．to figure out what’s blooming needs special knowledge |
| A．Lisa Benton. | B．David Inouye |
| C．Francisco Lopez. | D．Jake Weltzin. |
| A．changes in animals caused by global warming happen earlier than those in plants |
| B．the biological timing of earth is changing because of climate change |
| C．the effect of climate change in Tucson, Arizona can be hardly noticed |
| D．all the plants in Tucson, Arizona are blooming earlier because of climate change |
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