.

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．

72．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

73．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

74．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 people’s skin colour

75．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 gene for melanosome production

       C．they have fewer activities outside

       D．they pay much attention to protecting their skin

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科目：高中英語(yǔ) 來(lái)源： 題型：050

　　 I have a rule for travel:Never carry a map.Iprefer to ask for directions.

　　 Foreign visitors are often puzzled in Japan because most streets there don't have name.In Japan,people use landmarks in their directions instead of street names.For example,the Japanese will say to travelers, “Go straight down to the corner. Tun left at the big hotel and go pass a fruit market. The post office is across from the bus stop.”

In the countryside of the American Midwest,usually there are not many landmarks. There are no mountains, so the land is very flat(平坦的). In many places there are no towns or buildings with tell you directions and distance. In Kansas or Iowa, for example, people will say, “Go north two miles. Turn east,and then go another mile.”

　　 People in Los Angeles, California, have no idea of distance on the map: They measure distance by means of time, not miles. “How far away is the post office?” you ask.　　“Oh,” they answer, “It's about five minutes from here.”you say, “It's about five minutes from here.” You say, “Yes, but how many miles away is it?” They don't know.

Peop;e in Greece sometimes do not even try to give directions because visitors seldom understand thi Greek language. Instead of giving you the direction, a Greek will often say, “Follow me.” Then he'll lead you through the streets of the city to the post office.

Sometimes a person doesn't know the answer to your question, What happens in this situation? A New Yorker might say, “Sorry, I have no idea.” But in Yucatan, Mexico, no one answers, “I don't know.” People in Yucatan think that “I don't know” is impolite. They usually give an answer, often a wrong one.A visitor can get very, very lost in Yucatan!

　　 One thing will help you everywhere-in Japan, in the United States in Greece, in Mexico, or in any other place. You might not understand a person's words, but maybe you can understand his body language. He or she will usually turn and then point in the correct direction. Go iin that direction, and you may find the post office!

1.The passage mainly tells us that_______.

A.never carry a map for travel

B.there are not many landmarks in the American Midwest

C.there are different ways to give directions in different parts of the world

D.New Yorkers often say, “I have no idea,” but people in Yucatan, Mexico, never say this

2.In which place do people tell distance by means of time?

A.Japan.

B.American Midwest.

C.Los Angeles,California.

D.Greece

3.In the passage,_______countries are mentioned by the writer.

A.seven　　　　 B.four　　　　C.eight　　　　 D.five

4.Which of the following is wrong?

A.Travelers can learn about people's customs by asking questions about directions.

B.A person's body language can help you understand directions.

C.People in some places give directions in miles, but people in other places give directions by means of time.

D.People in different places always give directions in the same way: They usr street namees.

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科目：高中英語(yǔ) 來(lái)源：同步題 題型：閱讀理解

閱讀理解。
      Most people say" yes" much more readily than" no".
     A friend is moving house this weekend and would like some
help,and you agree. But, what you really wanted was relaxing at
home for a couple of quiet days,or a roommate spends the whole
weekend playing video games and wants to borrow your homework
for"reference". But,you've just finished it after working hard for a
whole day.
     Many people say" yes" to this kind of requests. They tend not
to consider their own interests and feelings,and are often angry with
themselves afterwards. Saying" no" requires courage and considerable
practice. " Everyone wants to be liked. " says Gabriele Steinki,a
German psychologist. "Saying'no'risks losing the affection of the
person asking for the favor. Or even a job. "The result is that many
people say"yes"just for keeping the peace. But experts say this is
regrettable. Anyone should have the right to say" no". In fact, rejecting
a request can even help to stabilize a relationship because it
expresses real affection. But,for peop'le accustomed to agreeing every
request,it's very distressing to say" no".
     Most people believe that if they say" no" ,they'll lose the affection
of the person. But the affection is important to them. This way
of thinking can be replaced by this:"If he only likes me because I
always do what suits him,then the price of this affection is too high
in the long term. "
    When people say " no", Steinki advises giving the reasons
calmly until the person gets the message.
1. What does the second paragraph tell us?  
A. In fact people are usually selfish.
B. Sometimes people say " yes" when they really want to say no .
C. It's not suitable to ask others to help at weekends.
D. It's disgusting to borrow homework for reference.
2. Many people don't say" no" though they really want to because    
A. they dare not offend the asker
B. they are afraid of breaking the good relationship with the asker
C. they don't care about their own feeling
D. they are good-tempered
3. The underlined word" distressing" can be replaced by "____ ".   
A. comfortable                      
B. funny
C. unnecessary                    
D. uncomfortable
4. The best title for the passage would be _____.  
A. You Need Courage to Say "No"
B. Saying" No"Is More Important Than Saying" Yes"
C. Saying " No" Would Bring Benefits
D. The Art of Saying " No"

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