Plants can’t communicate by moving or making sounds, as most animals do. Instead, plants produce volatile compounds (揮發(fā)性化合物) —— chemicals that easily change from a liquid to a gas. A flower’s sweet smell, for example, comes from such volatile compounds to attract insects such as bugs and bees.
Plants can also discover  volatile compounds produced by other plants. A tree under attack by hungry insets, for instance, may give off these chemicals in order to let other trees know about the attack. In response, the other trees may send off their chemicals to keep the bugs away —— or even chemicals that will attract the bugs’ natural enemies.
Now scientists have created a quick way to understand what plants are saying: a chemical sensor (傳感器) called an “electronic nose”. The “e-nose” can tell such compounds as plants make. When plants are attacked, scientists say, the e-nose could help quickly decide whether plants are being eaten by insects. But today, the only way to spot such insects is to inspect individual plants by observing them. This is a challenging task for managers of greenhouses, including those that can house thousands of plants. The research team is working with an e-nose that can recognize volatile compounds. Inside the device, 13 sensors chemically react with volatile compounds based on the interactions (相互作用), and then the e-nose will give off electronic signals that the scientists can analyze by using computer software.
To test the e-nose, the team presented it with healthy leaves from cucumber, pepper and tomato plants, all being common greenhouse crops. Then scientists collected samples of the air around damaged leaves from each type of crop. These plants had been damaged either by insects or by scientists who made holes in the leaves with a hole punch (打孔器).
The e-nose, it turns out, can identify healthy cucumber, pepper and tomato plants based on the volatile compounds they produce. It could also identify tomato leaves that had been damaged. But even more impressive, the device could tell which type of damage —— by insects or with a hole punch —— had been done to the tomato leaves.
With some fine-tuning (微調(diào)), a device like the e-nose can one day be used in greenhouses to quickly spot harmful bugs, the researchers say. A device like this can also be used to identify fruits that are perfectly ripe and ready to pick and eat, says Natalia Dudareva, a biochemist at Purdue University in West Lafayette, India, who studies smells of flowers and plants. Hopefully, scientists believe, the device can bring large benefits to greenhouse managers in the near future.
小題1:We learn from the text that plants communicate with each other by ______.
A．making some sounds
B．waving their leaves
C．producing some chemicals
D．sending out electronic signals
小題2:What did the scientists do to find out if the e-nose worked?
A．They fixed 13 sensors inside the device.
B．They presented it with all common crops.
C．They collected different damaged leaves.
D．They do tests on damaged and healthy leaves.
小題3:According to the writer, the most amazing thing about the e-nose is that it can ______.
A．pick out ripe fruits quite expertly
B．spot the insects in a very quick way
C．tell different damages to leaves
D．recognize unhealthy tomato leaves
小題4:We can infer from the last paragraph that the e-nose ______.
A．is unable to tell the smell of flowers
B．is not yet tested in greenhouses
C．is designed by scientists at Purdue
D．is helpful in killing harmful insects

小題1:C
小題2:D
小題3:C
小題4:B
植物會說話嗎？植物如何"交流"？本文中的科學(xué)家們正在嘗試用e-nose來測試植物受到傷害時的反應(yīng)。
小題1:細節(jié)理解題。從文章第一段中的"Instead，plants produce volatile compounds，chemicals that..."可知，植物通過它本身所產(chǎn)生的一種化學(xué)物質(zhì)來進行交流，所以答案選C。
小題2:推理判斷題。從文章第五段可知，為了證實e-nose的效果，科學(xué)家用受到傷害的葉子與健康的葉子來測試。所以選D。
小題3:細節(jié)理解題。從倒數(shù)第二段中的"But even more impressive，the device could tell which type of damage..."可知，最令人驚奇的是e-nose能夠分辨葉子受到的不同的"傷害"。
小題4:推理判斷題。從文章最后一段中的"could one day be used in greenhouses to..."推斷可知，e-nose還沒有運用到greenhouses中，由此推斷B是答案。
練習(xí)冊系列答案
相關(guān)習(xí)題

科目：高中英語 來源：不詳 題型：完形填空

During the first week of the term, every student was given a job for which they would be responsible for the rest of that school year.
Some jobs were more  26 than others, and the children were eager to be given one of the best ones. And the teacher would  27 who had been most responsible during the previous year. Among them Rita  28 . During the previous year she had followed all the teacher’s  29  perfectly.
But that year there was a big  30 . Each child received one of the normal  31 , like cleaning the blackboard. But Rita’s job was very  32  . She was given a little box containing some sand and one ant. And even though the teacher  33 that this ant was a very special ant, it  34 Rita. Most of her classmates felt sorry for her and even her father  35 Rita to ignore it.  36 , Rita preferred to show the teacher her error by making the unimportant task into a special job.
“ I will turn this little task into  37  great,” Rita said to herself.
So Rita started  38 her little ant. She gave the ant the best food, and it grew bigger than anyone had expected…
One day, the teacher  39  a man to the students and said he would tell them a  40  piece of news. The man said, “ Today they have announced the winner of the  41 , and this class is the winner! This class has been chosen to accompany me on a  42 to the tropical rainforest to investigate all kinds of insects.  43 all the schools of this region, it is this one that has best  44  for the little ant given to you. Well done!”
That day the class was filled with joy. Everyone  45 Rita and thanked the teacher. And many children learnt that to be given the most important tasks you have to know how to be responsible for even the smallest tasks.
小題1:
A．interestingB．possibleC．necessaryD．creative
小題2:
A．realizeB．doubtC．a(chǎn)rgueD．consider
小題3:
A．stood upB．stood outC．stood forD．stood by
小題4:
A．opinionsB．concernsC．instructionsD．experiments
小題5:
A．curiosityB．movementC．surpriseD．chance
小題6:
A．tasksB．promisesC．dreamsD．purposes
小題7:
A．differentB．ordinaryC．familiarD．valuable
小題8:
A．hopedB．insistedC．a(chǎn)greedD．guessed
小題9:
A．a(chǎn)nnoyedB．inspiredC．satisfiedD．disappointed
小題10:
A．supposedB．forcedC．encouragedD．a(chǎn)dmitted
小題11:
A．ThereforeB．OtherwiseC．HoweverD．Moreover
小題12:
A．somethingB．nothingC．everythingD．a(chǎn)nything
小題13:
A．developingB．studyingC．comfortingD．writing
小題14:
A．introducedB．exposedC．a(chǎn)ppealedD．connected
小題15:
A．terribleB．confusingC．wonderfulD．foolish
小題16:
A．competitionB．challengeC．conferenceD．negotiation
小題17:
A．journeyB．vacationC．meetingD．story
小題18:
A．BetweenB．AlongC．BesidesD．Among
小題19:A looked        B. paid        C. cared          D. worked
小題20:
A．prizedB．congratulatedC．respectedD．celebrated

查看答案和解析>>

科目：高中英語 來源：不詳 題型：閱讀理解

Futurologists predict that life will probably be very different in 2050.
TV channels will have disappeared. Instead, people will choose a program from a “menu” and a computer will send the program directly to the television. Today, we can use the World Wide Web to read newspaper stories and see pictures on a computer thousands of kilometers away. By 2050, music, films, programs, newspapers, and books will come to us by computer.
Cars will run on new, clean fuels and they will go very fast. Cars will have computers to control the speed and there won’t be any accidents. Today, many cars have computers that tell drivers exactly where they are. By 2050, the computer will control the car and drive it to your destination. Space planes will take people halfway around the world in 2 hours. Today, the United States Space Shuttle can go into space and land on Earth again. By 2050, space planes will fly all over the world and people will fly from Los Angeles to Tokyo in just 2 hours.
Robots will have replaced people in factories. Many factories already use robots. Big companies prefer robots — they don’t ask for pay rises or go on strike, and they work 24 hours a day. By 2050, we will see robots everywhere — in factories, schools, offices, hospitals, shops and homes.
Medical technology will have conquered many diseases. Today, there are devices（設(shè)備）that connect directly to the brain to help people hear. By 2050, we will be able to help blind and deaf people to see and hear again.
Scientist will have discovered how to control genes（基因）. Scientists have already produced clones of animals. By 2050, scientists will be able to produce clones of people, and decide how they look, how they behave and how clever they are. Scientists will be able to do these things, but should they?
小題1:We can learn from the passage that some big companies prefer robots to human workers, because human workers __________.
A．often ask for more pay
B．can work 24 hours a day
C．a(chǎn)re not clever enough
D．a(chǎn)re often late for work
小題2:The underlined word “conquered” in Paragraph 5 most probably means ________.
A．discoveredB．treatedC．causedD．cured
小題3:It can be inferred from Paragraph 5 that _________.
A．few diseases will attack people by 2050
B．there will be no blind and deaf people by 2050
C．medical technology will be more effective by 2050
D．devices are connected directly to the brain to help people hear
小題4:What is the author’s attitude towards the cloning technology?
A．The author does not support the use of cloning technology.
B．The author thinks human cloning is impossible.
C．The author does not really support the idea of human cloning.
D．The author is quite excited about human cloning.
小題5:According to the passage, which of the following can be realized today?
A．Read newspapers on a computer.
B．Make a space shuttle to go into the land.
C．Use computers to control car speed.
D．Choose TV programs freely from a “menu”.

查看答案和解析>>

科目：高中英語 來源：不詳 題型：閱讀理解

Imagine, one day, getting out of bed in Beijing and being at your office in Shanghai in only a couple of hours, and then, after a full day of work, going back home to Beijing and having dinner there.
Sounds unusual, doesn't it? But it's not that unrealistic, with the development of China’s high—speed railway system. And that’s not all. China has an even greater high-speed railway plan—to connect the country with Southeast Asia, and eventually Eastern Europe.
China is negotiating to extend its own high·-speed railway network to up to 17 countries in 10 to 15 years, eventually reaching London and Singapore.
China has proposed three such projects. The first would possibly connect Kunming with  Singapore via Vietnam and Malaysia. Another could start in Urumqi and go through Kazakhstan and Uzbekistan, and possibly to Germany. The third would start in the northeast and go north through Russia and then into Western Europe.
If China’s plan for the high-speed railway goes forward, people could zip over from London to Berlin in under two days.
The new system would still follow China’s high-speed railway standard. And the trains would be able to go 346 kilometers an hour, almost as fast as some airplanes.
China’s bullet train(高速客車),the one connecting Wuhan to Guangzhou, already has the   World’s fastest average speed. It covers 1,069 kilometers in about three hours.
Of course, there are some technical challenges to overcome. There are so many issues that need to be settled, such as safety, rail gauge(軌距),maintenance of railway tracks. So, it’s important to pay attention to every detail.
But the key issue is really money. China is already spending hundreds of billions of yuan on domestic railway expansion.
China prefers that the other countries pay in natural resources rather than with capital  investment. Resources from those countries could stream into China to sustain development.
It’ll be a win-win project. For other countries, the railway network will definitely create more opportunities for business, tourism and so on, not to mention the better communication among those countries.
For China, such a project would not only connect it with the rest of Asia and bring some much-needed resources, but would also help develop China’s far west. We foresee that in the coming decades, millions of people will migrate to the western regions, where the land is empty and resources unused. With high-speed trains, people will set up factories and business centers in the west once and for all. And they’11 trade with Central Asian and Eastern European countries.
小題1:China’s new high-speed railway plan will be a win-win project because     .
A．China will get much-needed resources and develop its western regions
B．China and the countries involved will benefit from the project in various ways
C．China will develop its railway system and communication with other countries
D．the foreign countries involved will develop their railway transportation, business and tourism
小題2:According to the passage, the greatest challenge to the new high-speed railway plan is     .
A．technical issues
B．safety of the system
C．financial problems
D．maintenance of railway tracks
小題3:Which of the following words best describes the author’s attitude towards China’s high-speed railway plan?
A．Critical.B．Reserved.C．DoubtfulD．Positive.
小題4:Which of the following might be the best title for the passage?
A．New Railway Standards
B．Big Railway Dreams
C．High-speed Bullet Trains
D．International Railway Network

查看答案和解析>>

科目：高中英語 來源：不詳 題型：閱讀理解

Americans with small families own a small car or a large one. If both parents are working, they usually have two cars. When the family is large, one of the cars is sold and they will buy a van(住房汽車)
A small car can hold(容納)four persons and a large car can hold six persons but it is very crowded(擁擠). A van hold seven persons easily, so a family three children could ask their grandparents to go on a holiday travel. They could all travel together.
Mr. Hagen and his wife had a third child last year. This made them sell a second car and buy a van. Their children sixth and seventh seat are used to put other things, for a family of five must carry many suitcases(衣箱)when they travel. When they arrive at their grandparents’ home , the suitcases are brought into the two seats can then carry the grandparents.
Americans call vans motor homes. A motor home is always used for holidays. When a family are traveling to the mountains or to the seaside, they can live in their motor home for a few days or to the seaside, they can live in their motor home for a few days or weeks. All the members of a big family can enjoy a happier life when they are traveling together. That is why motor homes have become very popular. In America there are many parks for motor homes.
小題1:From the passage, a van is also called ____________.
A．a(chǎn) motor carB．a(chǎn) motor homeC．a(chǎn) motorbikeD．a(chǎn) big truck
小題2:Before Mr. Hagen and his wife bought a van, they__________.
A．sold their old house
B．moved to their grandparents’ house
C．built a new place for a van
D．sold their second car
小題3:A motor home is usually owned by a family with__________.
A．a(chǎn) babyB．much money
C．more than two childrenD．interest in vans
小題4:Americans usually use motor homes____________.
A．to travel with all the family members of holiday
B．to do some shopping with all the family members
C．to visit their grandparents at weekends
D．to drive their children to school every day
小題5:Motor homes have become popular because___________.
A．they can take people to another city when people are free
B．they can let families have a happier life when they go out for their holidays
C．some people think motor homes are cheap
D．big families can put more things in motor homes

查看答案和解析>>

科目：高中英語 來源：不詳 題型：閱讀理解

Birds that are half-asleep — with one brain hemisphere (半球) alert(警覺) and the other sleeping — control which side of the brain remains awake, according to a new study of sleeping ducks.
Earlier studies have recorded half-brain sleep in a wide range of birds. The brain hemispheres take turns sinking into the sleep stage characterized by slow brain waves. The eye controlled by the sleeping hemisphere keeps shut, while the wakeful hemisphere’s eye stays open and alert. Birds also can sleep with both hemispheres resting at once.
Decades of studies of bird groups led researchers to predict extra alertness in the end-of-the-row sleepers which tend to be attacked more easily. Sure enough, the end birds tended to watch carefully on the side away from their companions. Ducks in the inner spots showed no preference for gaze(注視) direction.
Also, birds napping (打盹) at the end of the line depend on single-hemisphere sleep, rather than total relaxation, more often than inner ducks did. Turning 16 birds through the positions in a four-duck row, the researchers found that compared with 12 percent for birds in inner spots, outer birds half-asleep during some 32 percent of napping time.
“We believe this is the first evidence for an animal behaviorally controlling sleep and wakefulness at the same time in different regions of the brain,” the researchers say.
The results provide the best evidence for a long-standing assumption that single-hemisphere sleep developed over time as creatures scanned for enemies. The preference for opening an eye on the lookout side could be widespread, he predicts. He’s seen it in a pair of birds napping side-by-side in the zoo and in a single pet bird sleeping by a mirror. The mirror-side eye closed as if the reflection were a companion and the other eye stayed open.
Useful as half-sleeping might be, it’s only been found in birds and such water animals as dolphins, whales, and seals. Perhaps keeping one side of the brain awake allows a sleeping animal to surface occasionally to avoid drowning.
Studies of birds may offer unique insights into sleep. Jerome M. Siegel of the UCLA says he wonders if birds’ half-brain sleep “is just the tip of the iceberg.” He supposes that more examples may turn up when we take a closer look at other species.
小題1:According to the passage, birds often half sleep because ______.
A．they have to watch out for possible attacks
B．their brain hemispheres take turns to rest
C．the two halves of their brain are differently organized
D．they have to constantly keep an eye on their companions
小題2:What is implied about the example of a bird’s sleeping in front of a mirror?
A．An imagined companion gives the bird a sense of security.
B．Birds prefer to sleep in pairs for the sake of their security.
C．The phenomenon of birds napping in pairs is widespread.
D．A single pet bird enjoys seeing its own reflection in the mirror.
小題3:It can be inferred that _______.
A．Birds never sleep with both hemispheres resting at once.
B．Inner ducks depend on single-hemisphere sleep, rather than total relaxation, as often as birds napping at the end of the line do
C．It is not the first time for scientists to research on birds’ half-brain sleep
D．Birds hardly sleep without a companion
小題4:By saying “just the tip of the iceberg”, Siegel suggests that _______.
A．half-brain sleep has something to do with icy weather
B．the mystery of half-brain sleep is close to being solved
C．most birds living in cold regions tend to be half sleepers
D．half-brain sleep may exist among other species

查看答案和解析>>

科目：高中英語 來源：不詳 題型：閱讀理解

Just as some people think that certain numbers are lucky or unlucky, others believe that we can use numbers to understand our personalities, or predict what will happen to us in the future.
Numerology is a way of using numbers to describe a person’s character, and to make predictions about future life events. Numerologists use the numbers 1-9, 11 and 22 — also known as the “master” numbers — to help a person understand his or her personality, life goals, and destiny.
Numerologists consider your Life Path number to be the most significant because this number describes your character. To find this number, add together all the numbers in your date of birth. For example, a person born on April 25, 1985 would add the month (4), to the numbers of the date (2+5), plus the numbers of the birth year (1+9+8+5). In this case the total is 34, so this person’s life path number is 7(3+4). Numerologists believe that people with this number are peaceful and affectionate but can also be very reserved.
Your Expression number describes your talents and predicts how you should use these to fulfill your destiny in life. Numerologists assign a number between 1 and 9 to each of the letters in your name. These numbers are then added together in the same way as before to find your Expression number. Numerologists can also do calculations to predict when the most challenging periods of your life will be.
Numerologists also believe that the day a person is born is important. Each day of the month has a character description. People born on the fourth are said to be responsible, honest, and stubborn. People born on the fifteenth have very strong attachments to family and home. Those who celebrate their birthday on the thirtieth are artistic, creative, and imaginative, and often make good writers.
If we calculate the numerical value of our name and birth date, numerologists believe that we can learn more about our personalities. They also believe that we can predict our destinies, how our lives will progress, and what challenges we may face along the way. To the numerologist, numbers can be used in many more ways than we think.
小題1:If a person was born on November 8, 1995, what is his Life Path number?
A．7 B．8 C．9 D．11
小題2:To understand your abilities and how to use them in your life, you should calculate your ______.
A．Life Path number B．Expression number
C．birthdayD．name and birth date
小題3:According to the passage, a person born on the fifteenth tends to be _______.
A．stubborn B．home-lovingC．a(chǎn)rtistic D．imaginative
小題4:According to the passage, numerologists believe that _________.
A．Life Path number can be used to predict a person’s most challenging life periods
B．Expression number is the most meaningful for people to learn a person’s character
C．numbers can help people better understand themselves
D．numbers can be used to change a person’s future
小題5:The function of the passage is __________.
A．to raise doubts about the usefulness of numerology
B．to persuade readers about the benefits of the practices it describes
C．to describe some of the numerological practices and their purpose
D．to tease those who take such beliefs seriously

查看答案和解析>>

科目：高中英語 來源：不詳 題型：閱讀理解

Today just as technology changed the face of industry, farmers have undergone an "agricultural revolution". On the farm of today, machines provide all the power.
One of the most important benefits will be the farm computer. A few forward-looking farmers are already using computers to help them run their farms more efficiently. The computers help them keep more accurate records so they can make better decisions on what crops to plant, how much livestock to buy, when to sell their products, and how much profit they can expect. Many computer companies have been developing special computer programs just for farmers. Programs are being written for hog(豬) producers, grain farmers, potato farmers, and dairy farmers. In the future, farmers will be able to purchase computer programs made to their needs. Because of the growing importance of computers on the farm, students at agricultural colleges are required to take computer classes in addition to their normal agricultural courses. There can be no doubt that farmers will rely on computers even more in the future. While the old-time farm depended on horse power, and modern farms depend on machine power, farms of the future will depend on computer power.
Another technological advance which is still in the experimental stage is the robot, a real "mechanized hired hand" that will be able to move and, in some ways, think like a human being. Unlike farmers of the present, farmers of the future will find that many day-to-day tasks will be done for them. Scientists are now developing robots that will be able to shear(修剪) sheep, drive tractors, and harvest fruit. Even complex jobs will be done by robots. For example, in order to milk their cows, farmers must first drive them into the special barn(畜棚), then connect them to the milking machines, watch the machines, and disconnect them when they are finished. In the future, this will all be done by robots. In addition, when the milking is completed, the robots will automatically check to make sure that the milk is pure. The complete mobilization of the farm is far in the future, but engineers expect that some robots will be used before long.
小題1:Which sentence carries the main idea of the whole passage? 
A．The first sentence of the first paragraph.
B．The first sentence of the second paragraph.
C．The first sentence of the third paragraph.
D．The last sentence of the second paragraph.
小題2:Which of the following statements is true?  
A．Farmers in the future will depend totally on computers.
B．Both computers and robots have been in use on today's farms.
C．Farmers mainly use machines on their farms at present.
D．Farmers can do nothing without the help of computers on today's farms.
小題3: According to the engineers,_____________ will be done by robots in the near future.
A．a(chǎn)ll farm workB．milking cows
C．most of the farm workD．some house work
小題4:What is the best title for the passage?
A．Computer—Farmers' Best FriendB．Farmers in the Future
C．Robots in the futureD．Revolution on the farm

查看答案和解析>>

科目：高中英語 來源：不詳 題型：閱讀理解

On October 23, 2011, David Pologruto, a high school physics teacher, was stabbed (刺) by his smart student Jason Haffizulla. Jason got straight A’s and was determined to study medicine at Harvard, yet this was his downfall. His physics teacher gave Jason a B, a mark Jason believed would undermine (損害) his entrance to Harvard. After receiving his B, Jason took a butcher knife to school and stabbed his physics teacher.
How can someone as smart as Jason do something so dumb? Studies show there is little or no correlation between IQ and emotional intelligence.
During my early university years, I regarded myself as an intelligent guy. I got good marks in mathematics, physics, and other subjects. I thought such skills would surely give me a bright future. After one year of study with decent marks, I began to see two major classes of students. The first category of students turned up to few lectures, partied every weekend, enjoyed a great social life, and did minimal work to pass courses. The second category of students were intelligent and hard workers who got good grades and were very focused on their studies. Surely would these intelligent and hard-working students find the great jobs before the other lazier class of students?
Not so. Students are often shocked upon graduation that their qualifications are not as important as they once thought. Graduates enter the workforce only to realize that co-workers hate them and less intelligent people are the ones receiving promotions.
Educational skills are useless in some industries when interpersonal skills are absent. You can have great ideas, theories, and solve complex problems, but if you cannot effectively communicate in a persuasive and exciting manner by relating to your fellow humans, you will face an uphill battle in whatever challenges you encounter. It’s not that people dislike you because of your intelligence; it’s that people dislike you because you’re rude and not understanding. The intelligent person with poor communication skills is insensitive or unaware of others’ emotions.
小題1:Jason Haffizulla stabbed his physics teacher because       .
A．he was unfairly treated by his teacher
B．he was disappointed with his downfall
C．he was not smart enough at studies
D．he got a worse mark than usual
小題2:We can infer from the third paragraph that the author        in his early university years.
A．didn’t think communication skills were as important as intelligence
B．didn’t work hard
C．belonged to the first category of students
D．could keep a balance between social life and studies
小題3:Intelligent people are hated because       .
A．they can solve more complex problems
B．they can’t settle the challenges they meet
C．they are envied for their intelligence
D．they are not understanding enough
小題4:The main purpose of the text is to tell us       .
A．the relationship between IQ and emotional intelligence
B．what kind of students can succeed in college
C．smart people may have poorer communication skills
D．intelligent students will meet more challenges at work

查看答案和解析>>

同步練習(xí)冊答案