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 zebra fish 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 melanosomes(黑色素). The number, size and darkness of melanosomes per pigment cell determines skin color.
It appears that, like the golden zebra fish, 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 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.
64. The passage mainly tells us that ________.
A. people can not change their skin color without any pain
B. the new discovery could lead to search 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
65. 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
66. 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
67. 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
When you are curious about something, and want to know more about it, you can use the way of asking questions. Asking questio
ns i
s the first step to make discoveries and find interesting answers. The steps below can guide you during the research.
you want to learn? By asking questions. On your paper, start writing down questions about the dinosaurs as you think of them:
s can help you research your subject more widely.
| A．①④③② | B．②③①④ | C．③②④① | D．④③①② |
What does the underli
ned sentence “Armed with your list of questions” mean?
| A．Putting your list of questions under your arm. |
| B．Discussing your questions with your classmates. |
| C．Writing down your list of questions. |
| D．Taking your list of questions with you. |
According to the passage, which of the following is TRUE?
| A．You can find all the answers online. |
| B．Learn more, and you’ll have no questions. |
| C．During the research, you may keep finding new questions. |
| D．Asking questions is the only way for research. |
. The best title for this passage is.
| A．Discovering Dinosaurs | B．Asking Good Questions |
| C．Finding Subjects | D．Having Interesting Answers |
Buster Brown was a thief-and a good one，too，he thought . He’d never been caught by the police because he never took chances． He was always prepared for any unforeseen event or emergency.
Confidently，he stood outside the house of his intended victim(受害者)and read the sign on the front gate of the house．“Don't worry about the dog—be aware of the owner!”it said．Buster smiled and found his way in．
The house looked quite normal outside，but inside it was very exotic with fascinating objects on display．As he began putting them into his bag，a dog came into the room．It stopped when it saw Buster，then wagged its tail madly and went over to him，licking his outstretched hand．
"Good boy，”Buster whispered． “What a great guard dog you are—trying to lick me to death.”
Satisfied he'd made friends with the dog，Bluster began to wander round the house，choosing items to put in his bag．His
skilled eye picked out only the best antiques(古董)：a pair of silver candleholders，a silver tea-and-coffee service，etc．．His new friend，the dog，sat and watched，as if wondering what was happening．
“Well，boy，”Buster whispered，finally．“That might do．Any more and I won't be able to carry it!”He swung the heavy bag onto his shoulders, just as the lights came on, nearly blinding him. He shielded his eyes with his hand.
"You're a very silly person," the figure(身影) in the doorway said. As the man came closer, Buster could see he was well dressed. His face seemed familiar, but Buster couldn't quite be sure of the place where he had seen him before.
"You should have taken more notice of the sign outside," the man rasped. "I knew about this attempted robbery last week and I also know you will end up behind bars for 20 years. Fancy trying to rob the house of the world's greatest fortune-teller(算命先生)!" Why was Buster so confident?
| A．He was not afraid of dogs. | B．He knew the own er of the house lived alone |
| C．He had never been caught by the police. | D．The house had no security alarm. |
Which of the following is closest in meaning to the word "exotic" in the third paragraph?
| A．Messy and untidy. | B．Rich and expensive. |
C．Comfortable and calming. |
D．Foreign and unusual. |
How did Buster decide which objects to take?
| A．He took those that were easy to carry in his bag. |
| B．He took only the best antiques. |
| C．He took those that he knew he could sell easily. |
| D．He looked for silver objects. |
What punishment waits for Buster Brown?
| A．A prison sentence with hard labour. | B．A long prison sentence. |
| C．A heavy fine. | D．Community service for 20 years. |
First the ground shook in Haiti, then Chile and Turkey. The earthquakes keep coming har
d and fast this year, causing people to wonder if something evil (邪恶的) is happening underfoot. It’s not.
While it may seem as if there 
are more earthquakes occurring, there really aren’t. The problem is what’s happening above ground, not underground, experts say. More people are moving into big cities that happen to be built in quake zones, and they’re rapidly putt
ing up buildings that can’t withstand (经受) earthquakes, scientists believe. And around-the-clock news coverage (报道) and better earthquake monitoring(监测) make it seem as if earthquakes are ever-present.
“I can definitely tell you that the world is not coming to an end,” said Bob Holdsworth, an expert in tectonics (筑造学) at Durharn University in the UK.
A 7.0 magnitude quake in January killed more than 230,000 people in Haiti. Last month, an 8.8 magnitude quake--- the fifth-strongest since 1900—killed more than 900 people in Chile. And two weeks ago, a 6.0 magnitude quake struck rural eastern Turkey, killing at least 57 people.
On average, there are 134 earthquakes a year that have a magnitude between 6.0 and 6.9, according to the US Geological Survey. This year is off to a fast start with 40 so far—more than in most years for that time period.
But that’s because the 8.8 quake in Chile generated a large number of strong aftershocks, and so many quakes early this year skews (扭曲) the picture, said Paul Earle, a US seismologist (地震学家).
Also, it’s not the number of quakes, but their devastating impacts(破坏性的影响) that gain attention, with the death tolls (死亡人数) largely due to construction standards (building standard) and crowding, Earle added. “The standard mantra (咒语) is earthquakes don’t kill people, buildings do, ” he said.
There have been more deaths over the past decades from earthquakes, said University of Colorado geologist Roger Bilham. In an opinion colum
n last month in the journal Nature, Bilham called for better construction standards in the world’s big cities.
Of the 130 cities worldwide with populations of more than 1 million, more than half are prone (倾向于) to earthquakes, Bilham said.
Developing nations, where populations are growing, don’t pay attention to earthquake preparedness, Bilham said.” If you have a problem feeding yourself, you’re not really going to worry about earthquakes.”
Another reason quakes seem worse is that we’re paying attention more. The Haiti earthquake quickly followed by the 8.8 in Chile made everyone start to think.
But it won’t last, said US disaster researcher Deniis Mileti. “People are paying attention to the violent planet we’ve always lived on,” Mileti said.” Come back in another six months if there has been no earthquakes, m
ost people will have forgotten it again. ”What is the main idea of the article?
| A．The number of earthquakes is increasing this year. |
| B．The reasons why earthquakes are so devastating. |
| C．The reasons why recent earthquakes have struck large cities. |
| D．Why earthquakes seem to be more serious this year. |
Which of the following is NOT a reason for the seeming increase in earthquakes this year，
according to the article?
| A．Greater underground activity. |
| B．A larger number of buildings prone to damage during earthquakes. |
| C．Around-the-clock news coverage. |
| D．Better earthquake monitoring. |
According to the article, it is safe to say that ______.
| A．there is an evil force beneath the world’s surface |
| B．large cities are always built in quake zones |
| C．enough attention has been paid to reducing the impact of earthquakes |
| D．the earthquake in Chili caused many aftershocks. |
According to the article, the greater damage of earthquakes this year can be mainly caused by ______.
| A．the occurrence of larger earthquakes |
| B．not enough warnings about earthquakes |
| C．poor construction standards and overcrowding |
| D．an increase in large cities |
To what degree can a computer achieve intelligence？The answer to this question may lie in a newly-developed US computer program called Smarter Child and the Internet.
If you ran into Smarter Child online, you would be surprised at this kid’s huge memory. It can recite many facts. For example, Smarter Child knows every baseball player in every team this season.
He knows every word in the dictionary and the weather in every major city areas across the US. However, if you ask Smarter Child other questions, you get strange answers. A question about Smarter Child’s age returns. “One year, 11 days, 16 hours, 7 minutes, and 47 seconds!” Asking where he lives gets, “In a clean room in a high-tech building in California.”
Smarter Child uses the vast information on the World Wide Web as his memory bank. To answer questions about spelling, for instance, Smarter Child goes to American 
Heritage Dictionary online. For the weather, he visits www.intellicast.com.
Some scientists believe that by joining the many systems of the Internet, an artificial being with the combined knowledge of, say, Albert Einstein, Richard Nixon and Britney Spears could be born. However, if Smarter Child wants to think and learn on his own like the boy-computer David in the movie A. I. Artificial Intelligence, he must overcome two problems.
The first is that computers find it difficult to read web pages because the files are labeled in different ways. That’s why programmers need to tell Smarter Child where to look for the weather. It would be a much more difficult task to let him find it himself.
Another problem is that while Smarter Child can process information more exactly and faster than any human, he lacks common sense—a basic grounding of knowledge that is obvious to any young child. From the text we can infer that www.intellicast.com is a website .
| A．where we people can find Smarter Child |
| B．which is specially designed to help Smarter Child |
| C．where weather forecasts are made |
| D．which is about artificial intelligence |
It is probably most difficult for Smarter Child to.
| A．learn the ability to tell right behaviors from wrong ones. |
| B．tell us how to spell a difficult word |
| C．provide us with a famous poem by Shakespeare |
| D．tell us how the American government is run |
The underlined “it ” in Paragraph 6 refers to ________.
| A．where to look for the weather | B．Smarter Child. |
| C．a much more difficult task | D．to read web pages |
Which of the following is the best title for the passage?
| A．A New Web Child | B．Intelligence Development |
| C．Smarter Child | D．The Future of Internet |
People have wondered for a long time how their personalities and behaviors are formed．It is not easy to explain why one person is intelligent and another is not, or why one is cooperative and another is competitive．
Social scientists are, of course, extremely interested in these types of questions．They want to explain why we possess certain characteristics and exhibit certain behaviors．There are no clear answers yet, but two distinct schools of thought on the matter have developed．As one might expect, the two approaches are very different from one another, and there is a great deal of debate between proponents of each theory．The controversy is often referred to as “nature and nurture”．
Those who support the “nature” side of the conflict believe that our personalities and behavior patterns are largely determined by biological and genetic factors．That our environment has little, if anything, to do with our abilities, characteristics, and behavior is central to this theory．Taken to an extreme, this theory maintains that our behavior is predetermined to such a degree that we are almost completely governed by our instincts（本能）．
Proponents of the “nurture” theory, or, as they are often called, behaviorists, claimed that our environment is more important than our biologically based instincts in determining how we will act．A behaviorist, B．F．Skinner, sees humans as beings whose behavior is almost completely shaped by their surroundings．The behaviorists’ view of the human being is quite mechanistic; they maintain that, like machines, humans’ respond to environmental stimuli（刺激） as the basis of their behavior．
Socially and politically, the consequences of these two theories are far-reaching．In the US, for example, blacks often score below whites on standardized intelligence tests．This leads some “anature” proponents to conclude that blacks are genetically lower in status than whites．Behaviorists, on the contrary, say that the differences in scores are due to the fact that blacks are often robbed of many of the educational and other environmental advantages that whites enjoy, and that, as a result, they do not develop the same responses that whites do．
Either of these theories cannot yet fully explain human behavior．In fact, it is quite likely that the key to our behavior lies somewhere between these two extremes．That the controversy will continue for a long time is certain．This passage is mainly concerned with．
| A．relation between personality and behavior |
| B．relation between behavior and environment |
| C．different accounts of patterns of human behavior |
| D．different theories of the formation of human behavior |
The underlined word " proponents'' in paragraph 2 means．
| A．creators | B．advisors | C．advocates | D．judges |
In paragraph 5 , the author mainly writes about．
| A．the considerable influence of the two theories |
| B．differences between the blacks and whites |
| C．racial discrimination in the United States |
| D．different responds to intelligence tests |
What's the author's purpose in writing the passage?
| A．To call our attention to the changes of human behavior． |
| B．To urge scientists to do more research in social science． |
| C．To give us a detailed explanation of human behavior． |
| D．To present an argument in the field of social science． |