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 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 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. scientists have found out that people’s skin colour is determined by the gene

    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. people can not change their skin colour without any pain

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

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 has helped to find medical treatments for skin cancer

    D. there are two kinds of genes

The writer’s attitude towards the discovery is ________.

A. neutral                          B. negative                   C. positive                    D. indifferent


Ⅰ   语言知识及应用(共两节,满分45分)
第一节完形填空(共15小题;每小题2分.满分30分)
阅读下面短文,掌握其大意.然后从1—15各题所给的A、B、C和D项中,选出最佳选项,并在答题卡上将该项涂黑。
As the plane circled over the airport, everyone guessed that  1    was wrong .The plane was moving unsteadily(不稳定地)through the  2    , and the passengers were suddenly thrown forward. At that moment ,the air hostess(空中小姐) appeared. She looked very pale, but was quite  3      . Speaking quickly but almost in a whisper she told everyone that the pilot was badly ill and asked if any of the passengers knew anything about machines or at  4    knew how to drive a car. After a moment’s  5    , a man got up and followed the hostess into the pilot’s room.  6  the pilot aside, the man took his seat and listened carefully to the orders  7  were being sent by radio from the airport  8    . The plane was now dangerously  9    to the ground, but it soon began to   10    .
The man had to circle the airport several times in order to become familiar with the controls. But the danger had not yet passed. The terrible moment came when he had to  11    . Following orders, the man controlled the plane towards the airfield. It shook greatly  12     it touched the ground and then moved rapidly  13    the field, but after a long   14    it stopped safely. Outside, a lot of people, who had been watching anxiously, ran forward to  15    the “pilot ”on an excellent landing .
1. A. nothing               B. what                    C. something                D. the plane
2. A. airport            B. heaven                            C. air                           D. cloud
3. A. natural            B. calm                    C. worried                    D. excited
4. A. most               B. last                      C. first                         D. least
5. A. thought               B. quiet                    C. darkness                   D. hesitation
6. A. Moved            B. Sending               C. Moving                    D. Being put
7. A. they               B. that                      C. these                        D. this
8. A. down              B. below                  C. there                        D. nearby
9. A. up                  B. over                     C. close                        D. downstairs
10. A. fly                        B. go down               C. stop                        D. climb
11. A. land                B. drive                    C. rise                          D. set
12. A. as                B. before                      C. after                        D. until
13. A. above             B. onto                     C. around                            D. across
14. A. fly                        B. forward                C. run                          D. drive
15. A. congratulate        B. praise                   C. thank                       D. reward

请认真阅读下面短文,从短文后各题所给的A、B、C、D四个选项中,选出最佳选项题卡上将该项涂黑。
In eighteen thirty, only a few miles away from what is now the great city of Cincinnan,  Ohio, lay a   36 and almost endless forest.
The area had a few settlements   37  by people of the frontier. Many of them had already left the area for settlements further   39  the west. But among those   40  was a man who had been one of the first people to arrive there.
He lived alone in a house of logs surrounded   41 all sides by the great forest. He seemed a part of the darkness and   42  of the forest, for no one had   43  known him to smile or speak an unnecessary word. His simple needs were   44 by selling or trading the skins of wild animals in the town.
His little log house had a single door. Directly   45  was a window. The window was boarded up(堵住). No one could remember a(n)  46  when it was not. And no one knew why it had been   47 .  I imagine there are few people living today who ever knew the   48  of that window. But I am one, as you shall   49 .
The man's name was said to be Murlock. He   50  to be seventy years old, but he was really fifty. Something other than years had been the   51 of his aging.
His hair and long, full beard were white.  His gray,   52  eyes were sunken.  His face was wrinkled. He was tall and thin with drooping shoulders—like someone with many   53 .
I never saw him. These   54  I learned from my grandfather. He told me the man's story   55  I was a boy. He had known him when living nearby in that early day.

【小题1】
A.hugeB.heavyC.smallD.bright
【小题2】
A.discoveredB.createdC.establishedD.invented
【小题3】
A.visitedB.reachedC.leftD.loved
【小题4】
A.inB.forC.overD.to
【小题5】
A.movingB.remainingC.travelingD.hunting
【小题6】
A.alongB.byC.withD.on
【小题7】
A.silenceB.noisesC.brightnessD.freshness
【小题8】
A.neverB.everC.onceD.sometimes
【小题9】
A.understoodB.exchangedC.satisfiedD.offered
【小题10】
A.outsideB.insideC.beforeD.opposite
【小题11】
A.timeB.opportunityC.storyD.experience
【小题12】
A.openedB.closedC.destroyedD.protected
【小题13】
A.secreetB.structureC.formationD.construction
【小题14】
A.guessB.seeC.supposeD.feel
【小题15】
A.seemedB.happenedC.pretendedD.appeared
【小题16】
A.causeB.cureC.reasonD.affection
【小题17】
A.prettyB.livelyC.lifelessD.horrible
【小题18】
A.achievementsB.enemiesC.problemsD.dreams
【小题19】
A.lessonsB.detailsC.summariesD.ideas
【小题20】
A.becauseB.sinceC.whenD.although


A mouse looked through a hole in the wall to see the farmer and his wife opening a package; what food might it contain? He was astonished to discover that it was a mouse trap!
Running to the farmyard,the mouse shouted,warning everyone,“There is a mouse trap in the house,there is a mouse trap in the house.”The chicken,with her head high,glared at the mouse and said,“Shut up.Little Ugly.This is a great concern to you,but it has nothing to do with me:I can’t be troubled by it.”
The mouse turned to the pig and told him.“There is a mouse trap in the house.”“I am so sorry,Mr Mouse,”said the pig sympathetically,“but there is nothing I can do about it but pray;you are always in my prayers.”
The mouse turned to the cow,who said,“A mouse trap,am I in great danger,huh?”
Now the mouse had to face the farmer’s mouse trap alone.
That very night a sound was heard through the house,like that of a mouse trap catching its prey.The farmer’wife rushed to see what was caught.In the darkness,she did not see it was a big poisonous snake whose tail the trap had caught.The snake bit the farmer’s wife.The farmer rushed her to the hospital.She returned home with a fever.It is said that drinking fresh chicken soup will help treat fever,so the farmer took his sharp knife to the farmyard for the soup’s main ingredient.His wife’s sickness continued,so friends and neighbors came to sit with her around the clock.To feed them,the farmer killed the pig.The farmer’s wife did not get well,in fact,she died,and so many people came for her funeral.The farmer had the cow killed to provide for all of them to eat.
So next time when someone is facing a problem,don’t say that it has nothing to do with you.
【小题1】We could see from the passage that the mouse was          

A.good at cheating othersB.dishonest
C.kind and warm-hearted D.foolish
【小题2】Which of the following is NOT TRUE according to the passage?
A.The others help the farmer kill the cow.
B.The mouse trap was very practical.
C.The pig is more friendly than the other animals.
D.The farmer’s family had no friends at all.
【小题3】What can we learn from the story?
A.Traps can always cause chain reactions.
B.It is better to be safe than to be sorry.
C.Sometimes when the least of us is threatened,we all might be at risk.
D.To keep the balance of nature is the duty of us all.

第II卷非选择题(共45分)

V. Task-based reading 任务型阅读 1’ * 10 = 10’

请认真阅读下面短文,并根据所读内容在文章后图表中的空格里填入最恰当的单词。注意:每空不超过1个单词。

Oh, the things that I should see if I had the power of sight for just three days!

The fast day would be a busy one. I should call to me all my dear friends and look long into their faces, imprinting (刻上) upon my mind the outward (外表的, 表面的) evidences of the beauty that is within them, I should let my eyes rest, too, on the face of a baby, so that I could catch a vision of the eager, innocent (天真无邪的) beauty which precedes (在…之前, 先于) the individual's consciousness (意识) of the conflicts which life develops.

And I should like to look into the loyal, trusting eyes of my dogs--the serious, clever little Scottie, Darkie, and the strong, understanding Great Dane, Helga, whose warm, tender, and playful friendships are so comforting to me.

On that busy first day I should also view the small simple things of my home. I want to see the warm colors in the carpets under my feet, the pictures on the walls, the lovely small furniture that transforms a house into home. My eyes would rest respectfully on the books in dot-raised type which I have read, but they would be more eagerly interested in the printed books which seeing people can read, for during the long night of my life the books I have read and those which have been read to me have built themselves into a great shining lighthouse, showing me the deepest channels of human life and the human spirit.

In the afternoon of that first seeing day, I should take a long walk in the woods and intoxicate (使陶醉) my eyes on the beauties of the world of Nature trying desperately (拼命地) to absorb in a few hours the vast brilliance (才华, 才智) which is presenting itself to those who can see. On the way home from my woodland trip, my path would lie close to a farm so that I might see the patient horses ploughing (耕地) in the field and the peaceful content of men living close to the soil. And I should pray for the glory of a colorful sunset.

When darkness had fallen, I should experience the double delight of being able to see by man-made light which the genius of man has created to extend the power of his sight when Nature brings darkness.

In the night of that first day of sight, I should not be able to sleep, so full would be my mind of the memories of the day!

(by Helen Keller)

The first day what Helen Keller would do (66) _________ given three days to see

In the morning

●  Look long into the faces of all her dear friends so that she would (67) _______ upon her mind the outward (外表的, 表面的) the evidences of their beauty that is within them

●  Catch a vision of the eager, innocent beauty of a baby by resting her eyes on his face.

●  Look into the loyal, trusting eyes of her (68) _________

●  View the small simple things of her home such as warm colors, pictures, trifles.

●  Fix her eyes with (69)_____ on the books in raised type she has read and the printed books for seeing people with interest.

In the afternoon

● (70) _________ in the woods; intoxicate (使陶醉) her eyes on the beauties of the world of Nature and absorb in a few hours the vast brilliance of the world.

●  Walk past a farm, see the (71) ________ horses ploughing (耕地) in tile field and the peaceful content of men living close to the soil.

●  Pray for the glory of a colorful sunset.

In the (72)_______

(73) ___________the double delight of being able to see, helped by man-made light.

At night

I should not be able to sleep, so full would be her mind of the (74) _________ of the day!

From the passage we know in spite of her blindness Helen Keller' was still full of love for (75) ____________.

 

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