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科目:高中英語(yǔ) 來(lái)源: 題型:閱讀理解
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(變異) 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 1.5 million years ago to protect bodies from ultra-violet rays of the sun(太陽(yáng)光紫外線), 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 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.
The passage mainly tells us that ________.
A. people can not change their skin colour without any pain
B. the new discovery could lead to search into ways to change skin colour safely
C. pop king Michael Jackson often changed his skin colour as he liked
D. scientists have found out that people’s skin colour is determined by the gene
It can be inferred from the passage that ________.
A. nowadays people who want to change their skin colour 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 colour is determined by the pigment gene
C. find out the reason why the Africans’ skin colour is dark D. find out the ways of changing peopl’s skin colour
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 gen for melanosome 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. indifferent
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科目:高中英語(yǔ) 來(lái)源: 題型:閱讀理解
The whole body is covered with skin.The surface of the skin is dead(like the hair and the nails),but it is made from a living layer(層)just under the surface.The outside dead layers wear off(磨損)all the time,with new ones replacing them,and the body forms a totally new skin every three weeks.
The skin protects the body from the outside world and it passes information from the outside.It helps to keep water in the body and to keep the body at the same temperature.Becteria(細(xì)菌)can’t get in through the skin unless it is damaged.
If the weather is cold,the blood vessels(血管)in the skin squeeze down,or contract(收縮),so that as little blood as possible comes near the surface.This means that less warmth is lost to the outside.This makes the skin look pale,or even “blue”.At the same time,the hairs on the skin are pulled upright by tiny muscles.
When it is hot,the blood vessels expand(擴(kuò)大),or get wider again,to allow plenty of blood to run near the surface of the skin.This helps the body to lose heat,and the skin may look red.At the same time,the sweat glands(汗腺)produce more sweat,which cools the skin.
If your skin has ever been numb(麻木的),you will realize how important the feeling from the skin is.Nerves(神經(jīng))in the skin are sensitive(敏感的)to heat and cold,sharpness,hardness and softness,wetness and dryness and pain.If one is not able to feel these things,which can act as warnings,he is likely to be burned,cut or hurt in other ways.
The colour of the skin depends on special colour cells(細(xì)胞).These are just below the top layers of the skin.They are needed as protection from some harmful ray of the sun.The stronger the sun is,the more important it is to have a dark skin.People with pale skins may “tan”(曬黑)in the sun.This happens when the body produces extra colour cells in the skin for protection.In the sun,the skin produces a vitamin(vitamin D)which is needed for strong bones.
Which of the following statements is NOT true?
A.Our hair and nails are dead like the surface of the skin.
B.There is skin all over our body.
C.The skin of our bodies will be completely different in three weeks.
D.The surface of the skin is made of a living layer.
The second paragraph mainly tells us about______.
A.the functions of the skin
B.the information from the outside
C.the water in the body
D.the temperature of the body
Bacteria will get in through the skin______.
A.when one’s skin is numb
B.when one is ill
C.when the skin is cut
D.when the sweat glands produce more sweat
When the weather is cold,the skin will contract in order to______.
A.allow more blood near B.make the skin look blue
C.keep warmth D.help the body lose heat
The colour of the skin is determined by______.
A.the rays of the strong sun B.colour cells
C.top layers of the skin D.vitamin D
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科目:高中英語(yǔ) 來(lái)源:2011屆浙江省杭州高中高三第七次月考英語(yǔ)卷 題型:閱讀理解
You never see him, but they're with you every time you fly. They record where you are going, how fast you're traveling and whether everything on your airplane is functioning normally. Their ability to withstand almost any disaster makes them seem like something out of a comic book. They're known as the black box.
When planes fall from the sky, as a Yemeni airliner did on its way to Comoros Islands in the India ocean June 30, 2009, the black box is the best bet for identifying what went wrong. So when a French submarine (潛水艇) detected the device's homing signal five days later, the discovery marked a huge step toward determining the cause of a tragedy in which 152 passengers were killed.
In 1958, Australian scientist David Warren developed a flight-memory recorder that would track basic information like altitude and direction. That was the first mode for a black box, which became a requirement on all U.S. commercial flights by 1960. Early models often failed to withstand crashes, however, so in 1965 the device was completely redesigned and moved to the back of the plane – the area least subject to impact – from its original position in the landing wells (起落架艙). The same year, the Federal Aviation Authority required that the boxes, which were never actually black, be painted orange or yellow to aid visibility.
Modern airplanes have two black boxes: a voice recorder, which tracks pilots' conversations, and a flight-data recorder, which monitors fuel levels, engine noises and other operating functions that help investigators reconstruct the aircraft's final moments. Placed in an insulated (隔絕的) case and surrounded by a quarter-inch-thick panels of stainless steel, the boxes can resist massive force and temperatures up to 2,000℉. When submerged, they're also able to emit signals from depths of 20,000 ft. Experts believe the boxes from Air France Flight 447, which crashed near Brazil on June 1,2009, are in water nearly that deep, but statistics say they're still likely to turn up. In the approximately 20 deep-sea crashes over the past 30 years, only one plane's black boxes were never recovered.
【小題1】What does the author say about the black box?
A.It ensures the normal functioning of an airplane. |
B.The idea for its design comes from a comic book. |
C.Its ability to resist disasters is incredible. |
D.It is an indispensable device on an airplane. |
A.Data for analyzing the cause of the crash. |
B.The total number of passengers on board. |
C.The scene of the crash and extent of the damage. |
D.Homing signals sent by the pilot before the crash. |
A.New materials became available by that time. |
B.Too much space was needed for its installation. |
C.The early models often got damaged in the crash. |
D.The early models didn't provide the needed data. |
A.To distinguish them from the colour of the plane. |
B.To caution people to handle them with care. |
C.To make them easily identifiable. |
D.To conform to international standards. |
A.There is still a good chance of their being recovered. |
B.There is an urgent need for them to be reconstructed. |
C.They have stopped sending homing signals. |
D.They were destroyed somewhere near Brazil. |
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科目:高中英語(yǔ) 來(lái)源:2013-2014學(xué)年山東省高三10月份第一次質(zhì)檢英語(yǔ)試卷(解析版) 題型:其他題
閱讀下面短文并回答問(wèn)題,然后將答案寫到答題卡相應(yīng)的位置上(請(qǐng)注意問(wèn)題后的字?jǐn)?shù)要求)。
[1]Usually, when your teacher asks a question, there is only one correct answer. But there is one question that has millions of correct answers. That question is “What's your name?”. Everyone gives a different answer, but everyone is correct. Have you ever wondered about people's names? Where do they come from? What do they mean?
[2]People's first names, or given names, are chosen by their parents. Sometimes the name of a grandparent or other member of the family is used. Some parents ___________________. A boy could be named George Washington Smith;a girl could be named Helen Keller Jones.
[3]Some people give their children names that mean good things. Clara means “bright”; Beatrice means “one who gives happiness”;Donald means “world ruler”; Leonard means “as brave as a lion”.
[4]The earliest last names, or surnames, were taken from place names. A family with the name Brook or Brooks probably lived near a brook (小溪); someone who was called Longstreet probably Lived on a long, paved road. The Greenwood family lived in or near a leafy forest.
[5]Other early surnames came from people's occupations. The most common occupational name is Smith, which means a person who makes things with iron or other metals. In the past, smiths were very important workers in every town and village. Some other occupational names are:Carter—a person who owned or drove a cart;Potter—a person who made pots and pans. The ancestors of the Baker family probably baked bread for their neighbours in their native village. The Carpenter's greatgreatgreatgrandfather probably built houses and furniture.
[6]Sometimes_people_were_known_for_the_colour_of_their_hair_or_skin,or_their_size,or_their_special_abilities. When there were two men who were named John in the same village, the John with the gray hair probably became John Gray. Or the John who was very tall could call himself John Tallman. John Fish was probably an excellent swimmer and John Lightfoot was probably a fast runner or a good dancer.
[7]Some family names were made by adding something to the father's name. Englishspeaking people added s or son. The Johnsons are descendants of John; the Roberts family's ancestor was Robert. Irish and Scottish people added Mac or Mc or O. Perhaps all of the MacDonnells and the McDonneils and the O'Donnells are descendants of the same Donnell.
1.What is the best title of the passage? (no more than10 words)
_______________________________________________________
2.Please fill in the blank in the 2nd paragraph with proper words or phrases to complete the sentence.(no more than 10 words)
_______________________________________________________
3.According to the passage, what job did the ancestors of the Potter family most probably do?
_______________________________________________________
4.List three aspects that the surnames cover in the passage.
(1)___________ (2)___________ (3)___________
5.Translate the underlined sentence in the 6th paragraph into Chinese.
_______________________________________________________
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科目:高中英語(yǔ) 來(lái)源:2012-2013學(xué)年河南鄭州第四中學(xué)高三第十四次調(diào)考英語(yǔ)試卷(解析版) 題型:閱讀理解
Anyone who ever wondered why a dying plant, say, a freshly-cut red rose may appeal to a lady friend, might take some comfort in science, which once again offers us a reasonable answer to one of the world’ s great mysteries.
Beyond a common preference in people for blue, “the long history of color preference studies has been described as ‘confusing and contradictory,” write scientists Anya Hurlbert and Yazhu Ling of England’ s Newcastle University, authors of a new study in the journal Current Biology. “This fact is perhaps surprising,” they said, “though the popularity of the concept that little girls differ from boys in preferring pink.”.
But the scientists believe they have an answer to this scientific mystery, discovering women’s preference for red, hidden above the average liking for blue.
In their study, the pair quickly flashed color cards, displaying many different aspects, at 208 volunteers, mostly Britishers but with a number of Han Chinese, who moved to the United Kingdom recently. Tested in three different experiments, the researchers found out a small but significant preference for reddish colors in the female volunteers.
Puzzled, the authors realized that most of the difference between men and women came in the form of a preference for green VS red in the color cards, regardless of the other slight differences such as the slightly blue ones that everyone liked. Why might this be?
Evolution might offer an answer, they reason. Human color perception(感知), the assessment of three separate color types-red-green-blue-in our vision is a relatively recent addition to our line of mammals.
Adding weight to their argument, they found the women who are most typically feminine(女性的)on a psychological survey also had the biggest preference for reddish colors. “My love is like a red, red rose,” wrote the Scottish poet Rober Burns in 1794.
1.The scientists discovered the colour mystery that exists between men and women by _____..
A.giving examples B.doing experiments.
C.stating causes and effects D.interviewing volunteers.
2.The word “pair” in Para.4 refers to _____.
A.man and woman B.science and evolution .
C.Anya Hurlbert and Yazhu Ling D.red and green
3.According to the study the scientists have carried out in the passage, _____.
A.men like blue most.
B.women have preference for red besides blue.
C.generally speaking boys prefer slight pink to blue.
D.girls also love slight green.
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