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.
1. The passage mainly tells us that ________.
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A．people can not change their skin color without any pain |
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B．the new discovery could lead to research into ways to change skin color safely |
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C．pop king Michael Jackson often changed his skin color as he liked |
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D．scientists have found out that people’s skin color is determined by the gene |
2. It can be inferred from the passage that ________.
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A．nowadays people who want to change their skin color have to suffer a lot from the damage caused by the chemical treatment |
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B．Europeans and Africans have the same gene |
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C．the new discovery could help to find medical treatments for skin cancer |
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D．there are two kinds of genes |
3.Scientists have done an experiment on a dark-striped zebrafish in order to ________.
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A．find the different genes of humans’ |
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B．prove the humans’ skin color is determined by the pigment gene |
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C．find out the reason why the Africans’ skin color is dark |
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D．find out the ways of changing people’s skin color |
4.The reason why Europeans are light-skinned is probably that _____
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A．they are born light-skinned people |
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B．light-skinned Europeans have mutation in the gene for melanin production |
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C．they have fewer activities outside |
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D．they pay much attention to protecting their skin |
5.The writer’s attitude towards the discovery is ________.
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A．neutral（中立的） |
B．negative |
C．positive |
D．indifferent（冷漠） |
Many years ago my student asked me the question, "Mrs. Kindred, why do you teach?" Without taking time to reflect, I answered, "Because someday I might say something that might make a difference in someone's life." Even though I was sincere, that wasn't a very good answer and my student didn't let it slide.
"Let me get this straight," he said, "You went to college for four years so you could come here every day because you have the hope that someday you might say something that will influence someone?" He shook his head as if I were crazy and walked away looking confused. I'm one of those people who look back and wish they had said something smart or witty, or swift.
Even though that particular student might no longer wonder why I teach, there are days when I wonder. On those days, I remind myself of the real reasons I teach:
It's in my blood. My mother was my most influential teacher, and she was a 6th grade reading teacher until her death in 1990. She instilled (逐渐灌输) in me a love of reading and the knowledge that education opens doors.
Teaching is a way to make a difference. If you throw a stone in a pond the ripples go on and on until they reach the shore. You can't have ripples without a "stone." Good teachers throw stones that make a positive difference, and that's what I try to do.
I genuinely love teenagers. I want to share with others what I know and what I have learned through the years. Life is full of ups and downs, and if I can help students avoid some potholes on the road of life, I want to do so. If they'll allow me to celebrate their victories with them, I want to do too.
Teaching isn't for everyone, but I know I made the right career choice.
1.Why did the student continue to ask the question about the writer’s being a teacher?
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A．Because he thought her answer was unbelievable. |
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B．Because the writer was insincere. |
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C．Because the student was naughty. |
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D．Because the answer was difficult to understand. |
2.What do you think of the writer?
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A．Stupid. |
B．Honest. |
C．Conservative （保守的）. |
D．Polite. |
3. According to the text, which of the following is NOT true?
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A．The writer’s mother has the greatest influence on her. |
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B．The writer’s answer made the student confused. |
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C．In the writer’s opinion, some people in the world are unfit to teach. |
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D．The writer annoyed the student who asked the question. |
4.We can infer from the text that _________.
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A．the writer was also a good teacher in school |
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B．the writer often plays with her students beside a pond |
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C．the writer devotes herself to teaching and her students |
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D．the writer often accompanies the students on their way home |
5.What’s the main idea of the text?
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A．A student’s silly question. |
B．A good teacher who likes students. |
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C．A confused student. |
D．The reason why I teach. |
阅读下面短文，按照句子结构的语法性和上下文连贯的要求，在空格处填入一个适当的词或使用括号中词语的正确形式填空。
Nowadays, millions 1. lonely singles are now going online instead. 2._ World Wide Web is quickly becoming the world’s most popular matchmaker ( 媒人 ).
Singles are flocking (涌向) to the Internet _3.__ ( largeness ) because their busy lifestyles leave them little time to look for a significant other. Using dating sites (约会网址) is quick and convenient. Many singles say the regular dating scene 4. ( just lead ) them from one bad experience to __5._ and are ready to try something else. Dating sites also make 6. easy to avoid someone _7._ you are not interested in. In the real world, _8. , ignoring someone you don’t like can be difficult.
Despite all the advantages, online dating also presents its own set of problems. People aren’t always those who they declare to be in their online __9.__ ( describe ). Safety is another concern. You are just __10. ( like ) to find a criminal online as you are Mr. or Miss Right.
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。
Have you noticed that lightly rubbing your temple (太阳穴) on your head temporarily ease minor headaches?
I am not a medical doctor, and I have no idea why this 1 . I don’t even know if it really helps with headache pains or if it is only a 2 remedy (疗法). Frankly speaking, I don’t even know if it is 3 to do so. But it seems to work just fine for me, at least for 4 headaches.
If you know why it works or if it is safe, please let me know and I will add that information here.
I also 5 that I am not able to 6 rub my temples for a long period of time, if my headaches are persistent. So, I sometimes use a tight 7 or a tight adjustable hat to do the 8 so I don’t have to use my 9 . Just don’t make it too tight, or it will make your headache 10 .
This simple remedy does not 11 migraines (偏头痛). You should definitely ask your 12 before you try this relief, and especially if you get headaches 13 . It may be a 14 of a major medical problem that needs immediate 15 . I take no responsibility, so go to see a doctor immediately.
1. A. keeps B. happens C. works D. matters
2. A. medical B. special C. social D. psychological
3. A. safe B. strange C. efficient D. crazy
4. A. minor B. major C. serious D. daily
5. A. consider B. find C. fear D. insist
6. A. actually B. really C. gradually D. continuously
7. A. tool B. dress C. headband D. glove
8. A. work B. trick C. test D. enjoyment
9. A. doctor B. medicine C. knowledge D. hands
10.A. worse B. better C. bigger D. uglier
11.A. mean B. cure C. include D. damage
12.A. parents B. doctor C. friend D. neighbor
13.A. gradually B. never C. often D. occasionally
14.A. sign B. discovery C. character D. topic
15.A. rest B. rubbing C. attention D. action
第二节 读写任务（共 1小题；满分 25分）
阅读下面的短文，然后按照要求写一篇 150词左右的英语短文。
Teenagers’ secrets should be kept to themselves and no one else, their parents included, has the right to stick their nose into their private life.
As we know, teenagers are going through a special period of development both physically and psychologically. They are curious about and puzzled by the unexpected changes in their body and mind. What’s more, exposed to a world of adults, it is only too natural for them to begin imitating adults’ behaviors in secret. Boys begin to smoke and girls begin to spend time doing their hair and care more about what to wear. Some even begin to date with a girlfriend or boyfriend without letting their parents know. They are doing all this in secret because they are still unsure whether it is right to do so and afraid that, if found out by their parent, they will get misunderstood and even punished. In fact, in many cases, parents can not deal with such matters well but hurt their children’s feelings badly, making children unwilling to communicate with them any more. When this happens, it hurts terribly feelings of the family as well. Therefore, it sounds reasonable and acceptable that teenagers should keep their secrets to themselves instead of sharing them with their parents, who should give them the freedom in dealing with secrets.
【写作内容】
1. 以约30个词概括上面文章的要点；
2. 然后以约120个词就“青少年的秘密该不该与父母分享”这一话题发表你的看法，至少包含以下内容：
1）你是支持还是反对与父母分享秘密？
2）你支持或反对的理由是什么？
3）结合你的实际, 谈谈你是具体怎么做的？
【写作要求】
1. 在作文中可以使用自己亲身的经历或虚构的故事，也可以参照阅读材料的内容, 但不得直接引用原文中的句子；
2. 作文中不能出现真实姓名和学校名称。
3. 题目自拟。
【评分标准】概括准确，语言规范，内容合适，篇章连贯。
第一节 基础写作（共 1题；满分 15分）上周末我校在2600名学生中进行了有关“幸福感”的相关问题调查。数据如下：
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比例 |
“幸福感”的来源 |
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50% |
从父母或亲友的爱、从温暖的家庭生活中感受到幸福 |
|
30% |
从助人、捐赠、义卖中感受到幸福 |
|
10% |
从友情中感受到幸福 |
|
10% |
异于上述情况，从不同角度讲述自己的幸福感 |
|
评价：调查情况体现了学生们是热爱生活的，但同时也反映了他们生活面较窄、视野不够开阔。 |
【写作内容】 根据以上数据，写一篇短文，包括以下内容：
1. 调查时间、调查问题以及调查对象；
2. 数据的解读
3. 总体评价
[写作要求]1. 只能使用5个句子表达全部内容；
2. 文中不能出现真实姓名和学校名称。
[评分标准]句子结构准确，信息内容完整，篇章结构连贯
