Today we tell you about some new understanding of why cutting the main branch of a plant
or tree can lead to better development.
The findings are from researchers on two_continents.Professor Prezemyslaw Prusinkiewicz
of the University of Calgary in Canada led the research with scientists from Britain and Sweden.
Their study appears in the Proceedings of the National Academy of Sciences.
Researchers have known since the 1930s that the actively growing tip of a plant produces
a hormone(荷尔蒙)called auxin(生长素)．This hormone flows down the main stem.Scientists
say the auxin has an indirect effect on buds(芽)on the side of the stem to prevent branching.
T hese buds themselves also produce auxin.The research suggests that to grow,they have
to be able to export the hormone into the main stem.But the flow from the stem tip prevents
them from doing this.The researchers wanted to find out how this blocking happens.
Professor Prusinkiewicz is on leave in Australia,but he sent us an e－mail suggesting a
simple way to understand the process.Think of a major road crowded with traffic.So many
cars are on the main road that the cars on the side roads cannot enter.
The stem is like the crowded main road.The new research shows that the buds on the
side cannot export their auxin into the main stem because it is too full.But if that main shoot
is pruned(修剪),other buds below it can start exporting.They are no longer prevented from
growing.
Ottoline Leyser from the University of York says that after a plant is pruned,all the
inhibited(被抑制的)shoot tips compete with each other to grow.In doing this,the branches
influence each other's growth.Nearby shoot tips are more likely to affect each other than those
that are far apart from each other.
Professor Leyser says the strongest branches grow best,wherever they may be on the
plant.The study found that the main shoot grows the best of all not because of its position at
the top of the plant,but mostly because it got there first.
A．Researchers have recently found out that the growing tip of a plant produces hormones.
B．Auxin has a direct effect on buds to keep branches from growing.
C．Buds on the side of the stem can’t produce hormones.
D．In order to grow，the buds on the side of the stem export the hormones into the main stem.
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学业测评一课一测系列答案科目：高中英语 来源：浙江省余姚中学09-10学年度高一下学期课时训练二英语试卷 题型：阅读理解
第三节：阅读理解(共10小题，每小题2分，满分20分)
阅读下列短文，从每题所给的四个选项(A、B、C和D)中，选出最佳选项，并在答题纸上将该选项标号涂黑。
Good health is the most valuable thing a person can have, but one cannot take good health for granted. It is important to remember that the body needs proper care in order to be healthy. There are three things that a person can do to help stay in good shape: eat right food, get enough sleep, and exercise regularly.
Proper nutrition(营养) is important for good health. Your body cannot work well unless it receives the proper kind of “fuel”. Don’t eat too much food with lots of sugar and fat. Eat plenty of foods high in protein(蛋白质), like meat, fish, eggs and nuts. Vegetables and fruits are very important because they provide necessary vitamins(维他命) and minerals. However, don’t overeat. It is not helpful to be overweight.
Getting the proper amount of sleep is also important. If you don’t get enough sleep, you feel tired and easily get angry. You have no energy. Over a long period of time a little amount of sleep may even result in a change of personality(个性). Be sure to allow yourself from seven to nine hours of sleep each night. If you do, your body will feel strong and refreshed, and your mind will be sharp.
Finally, get plenty of exercise. Exercise firms the body, strengthens the muscles, and prevents you from gaining weight. It also improves your heart and lungs. If you follow a regular exercise program, you will probably increase your life-span(寿命). Any kind of exercise is good. Most sports are excellent for keeping the body in good shapes: basketball, swimming, bicycling, running and so on are good examples. Sports are not only good for your body, but they are enjoyable and interesting, too.
If everybody were to eat the right foods, get plenty of sleep and exercise regularly, the world would be a happier and healthier place. We would all live to be much older and wiser.
41. According to the passage, ______.
A .we should always keep fit
B. if we were healthy, we could spend our days in doing things with less sleep
C. one can eat a lot to stay in good shape
D. one needn’t take any exercise if he is healthy
42. In order to keep good health, ______.
A. we should eat a lot of sweets
B. one needs a large amount of fat
C. people should eat according to the foods nutrition
D. we must try to sleep now and then
43. Eating more and sleeping less ______.
A. can keep healthy B. is no good for you
C. gets you more energy D. will keep your personality
44. The writer explains ______ in this passage.
A. how to eat B. the importance of doing exercise
C. how to keep healthy D. what to eat
45. The title of the article should be ______.
A. Eating and Exercising B. How Vitamins Work in Man’s Body
C. Staying Healthy D. Sleeping Well
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科目：高中英语 来源：福建省2009-2010学年度高二下学期期中考试（英语） 题型：阅读理解
IV.阅读理解（共17小题；每小题２分，满分34分）
Like cats, geckos（壁虎）always land on their feet. If they happen to fall from a wall or leaf they’ve been climbing, a quick move of the tail makes sure that they always land on their feet first, a new study finds.
Geckos are truly built for climbing: their feet have hairy toes that can fix themselves to a wall or other vertical（竖直的）surfaces. However, geckos’ feet can’t always keep hold and they may fall to the ground. When geckos fall or jump off a wall, they always land stomach-side down. Geckos’ long tails become necessary during their falls, the new study shows.
Researchers did an experiment. They placed geckos up-side-down on the underside of a leaf. When they lost their foothold and fell, the geckos pitched （倾斜）their tails for balance. They then rotated（旋转）their tails to make their bodies rotate. As soon as they were right-side up, they stopped rotating. On average, it only took the geckos about a tenth of a second to right themselves so that they would land on their feet.
Cats use a different way to land on their feet after a fall. As their tails don’t have the power like geckos’ tails, cats can’t use them to right themselves. Instead they twist their bodies around mid-air.
Engineers are trying to build a robot that imitates the geckos’ climbing ability. A tail will be fixed to the robot to allow it to keep balance.
54. What do we know about geckos?
A. Their toes make it possible for them to walk on walls.
B. Their tails can fix them to a wall or other vertical surfaces.
C. They often land on their backs when they jump off walls.
D. It takes them a second to right themselves in mid-air.
55. How do cats avoid their injury during a fall?
A. By twisting their bodies. B. By fixing their toes to the ground.
C. By using their tails to right themselves. D. By landing upside-down.
56. Geckos’ special abilities have given engineers some new ideas to _________.
A. allow robots to climb vertical surfaces
B. reproduce geckos like robots
C. invent robots that can rotate on the ground
D. invent robots that can balance themselves using their tails
57. What is the text mainly talking about?
A. The interesting living habits of geckos. B. The differences between cats and geckos.
C. Why geckos always land on their feet. D. How geckos climb up vertical walls.
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科目：高中英语 来源：福建省2009-2010学年度高一下学期期中考试试卷（英语） 题型：阅读理解
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第三部分：阅读理解（共20小题；每小题2分，满分40分）
阅读下列短文，从每题所给的四个选项中选出最佳选项，并在答题卡上将该项涂黑。
An 80-year-old couple was having problems remembering things, so they decided to go to their doctor to get checked out to make sure nothing was wrong with them.
When they arrived at the doctor’s, they explained to the doctor about the problems they were having with their memory. After checking the couple out, the doctor told them that they were physically okay but might want to start writing things down and make notes to help them remember things. The couple thanked the doctor and left.
Later that night, while watching TV, the man got up from his chair and his wife asked, “Where are you going?”
He replied, “To the kitchen.”
She asked, “Will you get me a cup of ice cream?”
He replied, “Sure.”
She then asked him, “Don’t you think you should write it down so you can remember it?”
He said, “No, I can remember that.”
She then said, “Well, I would also like some strawberries on top. You had better write that down because I know you’ll forget that.”
He said, “I can remember that. You want a cup of ice cream with strawberries.”
She replied, “Well, I also would like some whipped cream on top. I know you will forget that so you’d better write it down.”
With anger in his voice, he said, “I don’t need to write that down! I can remember that.” He then went into the kitchen.
After about 20 minutes he returned from the kitchen and handed her a plate of bacon and eggs. She stared at the plate for a moment and said angrily, “I told you to write it down! You forgot my bread!”
56. The doctor suggested the couple that they should ____.
A. live with their children B. keep notes to improve their memory
C. do some sports D. have an operation
57. While watching TV, the wife asked her husband to take her ____.
A. some strawberries B. something in the kitchen
C. a plate of bacon and eggs D. ice cream with strawberries and whipped cream
58. After seeing the doctor, the couple ____.
A. changed their life totally B. followed the doctor’s advice
C. did anything as before D. found the way of taking notes helpful
59. The husband got angry because his wife ____.
A. asked him to take her an ice cream
B. complained he forgot to take her bread
C. asked him to take her a plate of bacon and eggs
D. reminded him to write down what he would do
60. From the passage we can infer that the old couple ____.
A. still had something wrong with their memory after seeing the doctor
B. had poor health, so they went to see their doctor
C. obeyed their doctor’s advice and carried it out successfully
D. got their memory improved after seeing the doctor
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科目：高中英语 来源：河南省2009-2010学年高一下学期5月月考英语试题 题型：阅读理解
三.阅读理解(40分)
Americans have contributed to many art forms, but jazz, a type of music, is the only art form that was created in the United States. Jazz was created by black Americans. Many blacks were brought from Africa to America as slaves. The black slaves sang and played the music of their homeland.
Jazz is a mixture of many different kinds of music. It is a combination (合并) of the music of west Africa, the work songs the slaves sang, and religious music. Improvisation(即兴创作)is an important jazz. This means that the musicians make the music up as they go along, or create the music on the spot. This is why a jazz song might sound a little different each time it is played.
Jazz bands formed in the late nineteenth century. They played in bars and clubs in many towns and cities of the South, especially in New Orleans.
New Orleans is an imitational seaport, and people from all over the world come to New Orleans to hear jazz.
Jazz became more and more popular. By the 1920s, jazz was popular all over the United States. By the 1940s, you could hear jazz not only in clubs and bars, but in concert halls as well. Today, people from all over the world play jazz. Jazz musicians from the United States, Asia, Africa, South America, and Europe meet and share their music at festivals on every continent. In this way, jazz continues to grow and change.
1．From the passage we know that_____________created jazz.
A．white American B．black Americans
C．West Africans D．Indian Americans
2．What is the main idea of this passage?
A．It mainly tell about the contributions made by Americans to music.
B．It is mainly about different kinds of music.
C．It is about how jazz bands formed.
D．It is mainly about the history of jazz.
3．It can be known from the passage that jazz bands have a history of_________.
A．about 100 years B．around 200 years
C．about 150 years D．around 250 years
4．What kind of characteristics does jazz have?
A． It is always changing.
B．It is only played in the United States.
C．It is completely different from other music.
D．It is played in bars, clubs and concert halls.
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科目：高中英语 来源：江苏省2009-2010学年度高一下学期期中考试英语试卷 题型：阅读理解
第三部分阅读理解 (共15小题；每小题2分，满分30分)
请认真阅读下列短文，从短文后各题所给的A、B、C、D四个选项中，选出最佳选项，并在答题卡上将该项涂黑。
A “blogger” is a person who writes on an Internet website called a “blog”. The word “blog” is a short way of saying “web log”, or “personal website”. Anyone can start a blog, and they can write about anything they like.
There are millions of blogs on the Internet today. They provide news, information and ideas to the people who read them. They contain links to other websites. And they provide a place for people to write their ideas and react to the ideas of others.
A research company called Perseus has studied more than 3,000 web logs. It says that blogs are most popular with teenage girls. They use them to let their friends know what is happening in their lives. The study also says that more than 100,000 bloggers stopped taking part in the activity after a year.
However, some people develop serious blogs to present political and other ideas. For example, the Republican and Democratic parties in the southern state of Kentucky recently started their own blogs. And American companies are beginning to use blogs to advertise their products.
At the same time, some long-standing blogs have ended. Last week, blogging leader Dave Winer closed his free blog service “weblogs.com”. He said the site became too costly to continue. He started the blog four years ago, and thousands of people had written on it. They are now upset because they did not know that the site was closed.
One blog that is still going strong is called Rebecca’s Pocket. Rebecca Blood created the website in 1999. She wrote about the history of blogs on the site. That article led to a book called The Weblog Handbook. It has been translated into four languages so far.
Miss Blood says Rebecca’s Pocket gets about thirty thousand visitors a month. She writes about anything and everything—politics, culture and movies. She recently provided medical advice. And she wrote about how to prevent being stolen from online bank accounts.
1. The text is mainly written to ________.
A. introduce an Internet website called “blog” B. tell readers about blogs
C. introduce a short way of saying “web log” D. tell readers how to write blogs
2. From the text we can learn that blogs cover almost everything except ________.
A. different ideas B. medical advice
C. advertisements D. account passwords
3. Which of the following statements is NOT true according to the text?
A. Politicians don’t use blogs at all.
B. A lot of bloggers no longer write or read blogs.
C. Those who like to use blogs are mostly teenage girls.
D. Dave Winer closed his “weblogs.com” because of the money shortage.
4. The reason why Rebecca’s Pocket is still going strong is that ________.
A. it was created by a woman B. it is about the history of blogs
C. it provides useful information and advice
D. it has editions in at least four different languages
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