Mosquitoes have an extraordinary ability to target humans far away and fly straight to their unprotected skin. Regrettably, mosquitoes can do more than cause an itchy(發(fā)癢的)wound. Some mosquitoes spread several serious diseases, including Dengue, yellow fever and malaria.
Over one million people worldwide die from these diseases each year. New research now shows how mosquitoes choose who to bite.
Mosquitoes need blood to survive. They are attracted to human skin and breath. They smell the carbon dioxide gas, which all mammals breathe out. This gas is the main way for mosquitoes to know that a warm-blooded creature is nearby.
But mosquitoes also use their eyes and sense of touch. Michael Dickinson is a professor at the California Institute of Technology. His research shows how these small insects, with even smaller brains, use three senses to find a blood meal.
Michael Dickinson’s team used plumes—a material that rises into the air of carbon dioxide gas into a wind tunnel. They then used cameras to record the mosquitoes. The insects followed the plume.
Then, the scientists placed dark objects on the lighter colored floor and walls of the tunnel. Mr Dickinson said, at first, the mosquitoes showed no interest in the objects at all.
“What was quite striking and quite surprising is that the mosquitoes fly back and forth for hours. These are hungry females and they completely ignore the objects on the floor and wall of the tunnel. But the moment they get a hit of CO2, they change their behavior quite obviously and now would become attracted to these little visual blobs (斑點(diǎn)).”
This suggested to the researchers that a mosquito’s sense of smell is more important in the search for food. Once mosquitoes catch a smell of a human or animal, they also follow visual signals.
1.What do mosquitoes mainly use to find their targets?
A. Sense of smell. B. Sense of touch.
C. Sense of sight. D. Smart brains.
2.The first response of the mosquitoes to the objects in the experiment is .
A. to fly to the dark ones
B. to catch and stick to them
C. to take no notice of them
D. to attach themselves to them
3.How can we avoid being attacked by mosquitoes according to the text ?
A. Don’t let them see us.
B. Use dark objects to stop them.
C. Make them fly back and forth for hours.
D. Attract them to objects full of carbon dioxide gas.
4.What can be the best title for the text?
A. How Do Mosquitoes Survive?
B. Why Do Mosquitoes Need Blood?
C. How Do Mosquitoes Choose to Bite You?
D. Why Do Mosquitoes Attack the Human Being?
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科目:高中英語(yǔ) 來(lái)源:2015-2016學(xué)年湖南益陽(yáng)箴言中學(xué)高一下學(xué)期3月考英語(yǔ)試卷(解析版) 題型:閱讀理解
There are four main areas when it comes to your dog’s body language — his ears and face, eyes, nose and tail. If you pay attention to those things, you’ll find you are able to easily understand how your dog is feeling.
Ears and face
The head of a dog is more expressive than you think. If you say a word that he recognizes, like his name or something you say often, his ears will get up. His mouth is another good instruction. A mouth that is wide open to pant (喘氣) with some sound suggests that the dog is happy — some people even say when a dog is panting, he is laughing as he cools himself. A tongue sticking out suggests that the dog is in a good mood.
Eyes
To a dog, purple and blue are both seen as shades of blue. Red is seen as black or dark grey. Orange, yellow and green are seen as various shades of yellow. This means that, to a dog, bright orange toys are the same yellow shade. If you want your dog to clearly see his toys in the green grass you’d better give the dog blue toys; if you have orange, yellow or green toys, the dog will be able to find them with his nose.
Nose
A dog can both sniff and breathe through his nose. Breathing is for air, but when dogs sniff with short breaths they are actually following some scents (氣味) with his keen (靈敏的) nose. When a dog is overheated, his sense of smell is reduced by as much as 40 percent and he uses the air to cool himself rather than for smelling. Puppies’ noses can help find their mother when their eyes and ears are closed. The function will disappear by the time they are adults.
Tail
Lastly, you need to pay attention to your dog’s tail, because it shows what he is thinking and feeling. A dog that is in a good mood will have a tail that seems to be going a mile a minute — wagging, and excited. However, an angry or frightened dog will have his tail between his legs.
1.The author’s purpose in writing the first paragraph is to _____.
A. advise you to look after your dog
B. introduce the topic of the passage
C. explain what is body language
D. call on anyone to protect dogs
2.When your dog feels happy, he will _____.
a. keep his mouth wide open soundlessly
b. bark all the time in front of you
c. open his mouth to breathe with some sound
d. keep his tongue sticking out
A. a, b B. c, d C. a, d D. b, c
3.Why does your dog use his nose when looking for orange, yellow or green toys in the grass?
A. Because he wants to show how keen his nose is.
B. Because his nose is keener than his eyes in the open air.
C. Because he can’t tell the difference between toys and grass.
D. Because these colors are all shades of yellow in his eyes.
4. Which of the following is TRUE according to the last two parts “Nose” and “Tail”?
A. Adult dogs can’t use their nose to find their mothers.
B. When a dog feels too hot, he will lose his sense of smell.
C. Dogs often sniff with short breaths when they feel sad.
D. A dog’s tail can’t show his feelings unless he is frightened.
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科目:高中英語(yǔ) 來(lái)源:2016屆湖南郴州市高三第一次教學(xué)質(zhì)量監(jiān)測(cè)英語(yǔ)試卷(解析版) 題型:閱讀理解
People who are slightly overweight or mildly obese(肥胖的) have a lower risk of early death than normal weight individuals(個(gè)人;個(gè)體), according to a new analysis of nearly 100 international studies.
The studies, most conducted within the past decade, included about three million adults from around the world. The result of these studies by researchers at the National Center for Health Statistics in Maryland, part of the U.S. Centers for Disease Control and Prevention, shows that slightly overweight or obese people were six percent less likely to die from all causes compared to people of normal weight. But the researchers found that seriously obese individuals were still at a 30 percent greater risk of death compared to healthy-weight individuals.
Study lead author Katherine Flegal says she was not surprised that overweight people would not have a higher death risk. “Because we'd actually already read a lot of this literature and realized that death rates for overweight would be at least not higher than normal[weight," she said. “I guess l was a little bit surprised that it was definitely lower. And l was also surprised that the lower rates of obesity didn't seem to differ from normal weight."
But Flegal stresses the difference in death rates appear to be small between normal-weight people and overweight and mildly obese individuals.
The finding by Flegal and colleagues have raised new questions about the reliability(可靠性)of the so-called "body mass index" or BMI, a measurement of body fat as a ratio(比例,比率)of height to weight, that has become popular in recent years among public healthexperts to measure potential health risks.
But Heymsfield warns that individuals should not conclude that it's okay to put on extra kilograms, since being at a healthy weight lowers the risk for heart disease and diabetes.
1.Katherine Flegal feels surprised at the fact that____.
A. obese people have higher death rates
B. slightly obese people have lower death rates
C. obese people tend to die early
D. death rates have nothing to do with body weight
2.What do we learn from the fifth paragraph?
A. BMI may not be so reliable.
B. The study provides further evidence for BMI.
C. BMI tells nothing about potential health risks.
D. BMI has been much questioned recently.
3.What can we conclude from the passage'?
A. It's OK to put on extra weight.
B. It doesn't matter if you are slightly obese.
C. Obese people are much healthier.
D. Body weight has nothing to do with death rates.
4.What topic does the passage mainly deal with?
A. Technology. B. Dieting. C. Health. D. Death.
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科目:高中英語(yǔ) 來(lái)源:2015-2016學(xué)年江西豐城中學(xué)高一下學(xué)期第一次月考英語(yǔ)試卷(解析版) 題型:七選五
根據(jù)短文內(nèi)容,從短文后的選項(xiàng)中選出最佳選項(xiàng),選項(xiàng)中有兩項(xiàng)為多余選項(xiàng)。
Cheating is when a person misleads, deceives or acts dishonestly on purpose. 1. . If a basketball team is for kids under 8, it's cheating for a 9-year-old play on the team. At school, in addition to cheating on a test, a kid might cheat by stealing someone else's idea for a science project. 2. .This kind of cheating is called plagiarizing (抄襲).
3. . Jeff is doing it by sneaking(暗中的) answers to a test. And it's also cheating to break the rules of a game or contest or to pretend something is yours when it isn't. When people cheat, it's not fair to other people. It's tempting(誘惑人的) to cheat because it makes difficult things seem easy, like getting all the right answers on the test. 4. , and it won't help on the next test unless the person cheats again.
5. . They want to get good grades but hate hard work. Other kids might feel like they can't pass the test without cheating. Even though there seems to be a "good reason" for cheating, cheating isn't a good idea.
A. For kids, cheating may happen at school, at home, or while playing a sport.
B. Some kids cheat once and feel so bad that they never do it again.
C. Some kids cheat because they're lazy.
D. Kids may also cheat by copying a book report off the Internet and handing it in as it's his or her original work.
E. Cheating can happen in a lot of different ways.
F. But it doesn't solve the problem of not knowing the material(材料).
G. There are plenty of reasons why a kid shouldn't cheat, but some kids have already cheated.
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科目:高中英語(yǔ) 來(lái)源:2015-2016學(xué)年廣東廣州南沙區(qū)第一中學(xué)高二下學(xué)期第一次月考英語(yǔ)卷(解析版) 題型:單詞拼寫
根據(jù)首字母或中文提示,完成下列單詞
1.My children have become hopelessly a_________ to television.
2.She found it necessary to a__________ her child to getting up early.
3.With exams only a week away, I am under a lot of s_____.
4.The door opened _______(自動(dòng)地) as we approached.
5.Some ______ (年青人)have got into the habit of taking drugs.
6.A _______(廣泛傳播的)flu epidemic affected eighteen western states.
7.There has been serious _______(分歧) between the two political over the question.
8.The _______(平均數(shù))of 3, 6and 9 is 6.
9.The food was enough in q______, but not very good in quality,
10.Though he is less than one year old, he is strong enough to walk s______
11.She can’t see very well_________ her glasses.
12.It’s so hot today. I______________ going swimming.
13.You have made a few mistakes, but _____ you have done well.
14.Tu Youyou had no time to come to “Touching China”, and thus his colleague would accepted the award _____________ her.
15.Public opinion _____________ the war, and people call for the peace.
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科目:高中英語(yǔ) 來(lái)源:2016屆江西吉水中學(xué)高三第五次月考英語(yǔ)試卷(解析版) 題型:語(yǔ)法填空
閱讀下面材料,在空白處填入適當(dāng)?shù)膬?nèi)容(1個(gè)單詞)或括號(hào)內(nèi)單詞的的正確形式。
Now if you’ve got nothing to do today, why not go to the east part of the city and get digging? That’s the message from No.1 Senior High School, _1.__ is organizing a tree planting event near East Mountain. In order to improve the environmental _2._ (educate) of its students and get more people __3._ (organize), the school is planning to plant __4.__ total of 1,400 trees paid by the government over the next few days. They are hoping to plant half of them today and they __5.__(look) for volunteers to come along and help. No experience is necessary, __6.__ there will be experts to give directions and the __7.__ (equip) will be provided. Everyone is welcome to come along anytime __8.__ 10 am and 4 pm. I don’t think you need my advice of what sort of shoes or clothes you have to wear. And of course, gloves will be essential _9.__ (protect) your hands. So it could be10. (real) a nice day out for all the families. Enjoy your day.
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科目:高中英語(yǔ) 來(lái)源:2015-2016學(xué)年河南周口中英文學(xué)校高一下學(xué)期第一次月考英語(yǔ)卷(解析版) 題型:書面表達(dá)
書面表達(dá)
中國(guó)人出國(guó)旅游的不文明行為越來(lái)越受到廣泛關(guān)注。請(qǐng)以表格中所列舉的事實(shí)為依據(jù),寫一則英語(yǔ)短文,談?wù)勛约旱目捶ā?/p>
不文明行為 | 你的看法 |
在公共場(chǎng)所: 隨地吐痰 亂丟垃圾 大聲喧嘩 …… | 注意言談舉止 愛護(hù)環(huán)境 維護(hù)中國(guó)人的形象 …… |
注意:
1. 文章必須包括表格中的提示內(nèi)容,可以增加細(xì)節(jié)使行文連貫;
2. 詞數(shù)100左右;
3. 開頭已經(jīng)給出,不計(jì)入總詞數(shù);
4. 參考詞匯:亂丟 (垃圾) litter;吐痰 spit;形象 image;聲譽(yù) reputation
As more and more Chinese go traveling abroad, reports about their bad manners flood in.
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科目:高中英語(yǔ) 來(lái)源:2015-2016學(xué)年河北石家莊一中高二下學(xué)期一次月考英語(yǔ)卷(解析版) 題型:閱讀理解
Just 10 years ago, I sat across the desk from a doctor. “Yes,” he said, “there is something wrong with the left, upper lobe(肺葉). You have a moderately advanced case... You'll have to give up work at once and go to bed. Later on, we'll see.”
Feeling like a man who is in mid?career has suddenly been placed under sentence of death, I left the doctor's office, walked over to the park, and sat down on a bench. I needed to think. In the next 3 days, I cleared up my affairs, then I went home, got into bed, and set my watch to tick off not the minutes, but the months. Two years later, I left my bed and began the long climb back. It was another year before I made it.
I speak of this experience because these years that passed so slowly taught me what to value and what to believe. I realise now that this world I'm living in is not my oyster(牡蠣) to be opened but my opportunity to be grasped. Each day, to me, is a precious thing. The sun comes up and presents me with 24 brand?new, wonderful hours—not to pass, but to fill.
I've learned to appreciate those little, all?important things I never thought I had the time to notice before:the play of light on running water, the music of the wind in my favourite pine tree. I seem now to see and hear and feel with some of the recovered freshness of childhood. How well, for instance, I recall the touch of the springy earth under my feet the day I first stepped upon it after the years in bed.
Frequently, I sit back and say to myself, “Let me make note of this moment I'm living right now, because in it I'm well, happy and hard at work doing what I like best to do. It won't always be like this, so while it is, I'll make the most of it—and afterwards, I remember—and be grateful. All this, I owe to that long time spent on the sidelines of life.”
1.Which word can best describe the author's feeling after visiting the doctor?
A. Hopeless. B. Curious.
C. Confused. D. Energetic.
2.How long did it take the author to recover from his disease?
A. Two years and a half. B. Three years.
C. Three years and a half. D. Four years.
3.The underlined words “these years” in Paragraph 3 refer to the years when the author ________.
A. was ill
B. started his career
C. cleared up his affairs
D. struggled to go back to his work
4.By fighting with his disease, the author realised ________.
A. patients should know how to get on with doctors
B. doctors should treat patients more carefully
C. we should pay enough attention to diets
D. we should value and appreciate life
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科目:高中英語(yǔ) 來(lái)源:2015-2016學(xué)年天津新華中學(xué)高二下學(xué)期第三次月考英語(yǔ)卷(解析版) 題型:單項(xiàng)填空
_______ the morning train, he would not have been late for the meeting.
A. Did the catch B. Should he catch
C. Has the caught D. Had he caught
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