题目
题型:不详难度:来源:
Plants can also detect volatile compounds produced by other plants. A tree under attack by Hungry insets, for instance, may give off volatile compounds that let other trees know about the Attack. In response, the other trees may send off chemicals to keep the bugs away ——or even Chemicals that attract the bugs’ natural enemies.
Now scientists have created a quick way to understand what plants are saying: a chemical Sensor(传感器)called an electronic nose. The “e-nose” can tell compounds that crop plants make When they’re attacked Scientists say the e-nose could help quickly detect whether plants are being Eaten by insects. But today the only way to detect such insects is to visually inspect individual Plants. This is a challenging task for managers of greenhouses, enclosed gardens than can house Thousands of plants.
The research team worked with an e-nose than recognizes volatile compounds. Inside the device, 13 sensors chemically react with volatile compounds Based on these interactions, the e-nose gives off electronic signals that the scientists analyze using computer software.
To test the nose, the team presented it with healthy leaves from cucumber, pepper and tomato plants, all common greenhouse crops. Then scientists collected samples of air around damaged leaves from each type of crop, These plants had been damaged by insects, or by scientists who made holes in the leaves with a hole punch(打孔器). The e-nose, it turns out, could 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, a device like the e-nose could one day be used in greenhouses to quickly spot harmful bugs, the researchers say. A device like this could 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, Ind. who studies smells of flowers and plants. Hopefully, scientists believe, the device could bring large benefits to greenhouse managers in the near future.
小题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 |
A.They presented it with all common crops. |
B.They fixed 13 sensors inside the device. |
C.They collected different damaged leaves. |
D.They made tests on damaged and healthy leaves. |
A.pick out ripe fruits |
B.spot the insects quickly |
C.distinguish different damages to the leaves |
D.recognize unhealthy tomato leaves |
A.is unable to tell the smell of flowers |
B.is not yet used in greenhouses |
C.is designed by scientists at Purdue |
D.is helpful in killing harmful insects |
答案
小题1:C
小题2:D
小题3:C
小题4:B
解析
小题1:推理判断题。从句中"Plants can"t communicate by moving or making sounds, as most animals do. Instead, plants produce volatile compounds, chemicals that easily chasse from a liquid to a gas",可知选C。
小题2:细节理解题。从文章倒数第三段To test the nose, the team presented it with healthy leaves from-----可以找到答案D。
小题3:细节理解题。由倒数第二段"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. "可知答案C。
小题4:推理判断题。由"With some fine tuning, a device like the e-nose could one day be used in greenhouses to quickly ….,one day是关键,可推断选B。
核心考点
试题【Plants can’t communicate by moving or making sounds, as most animals do. Instead】;主要考察你对题材分类等知识点的理解。[详细]
举一反三
The trees take dust, ammonia and odors in their leaves. They also provide shade from the sun, so they reduce cooling costs in summer. And they act as a windbreak, so they reduce heating costs in winter. Trees can also improve water quality around farms by removing pollutions from soil and groundwater.
Several years ago, people were objecting to the odor of poultry farms on the Delmarva Peninsula in the eastern United States. Delmarva is where the states of Delaware, Maryland and Virginia come together. Two thousand farms there can each house an average of seventy-five thousand chickens.
Traditionally the farms used windows to provide fresh air in the chicken houses. Farmers rarely planted trees or tall crops around the buildings, so there would be no barrier to the airflow. But then farms began to use new ventilation systems. Instead of windows, the new systems used tunnel fans to circulate air. The fans directed airflow from the poultry houses toward the homes of neighbors.
Researchers began dealing with the problem in two thousand. They found that over a period of six years, planting three rows of trees reduced total dust and ammonia by more than half. And they found that smells were reduced by eighteen percent.
Farmers may think trees will take too long to grow and be effective. But some trees can grow quickly. At least one-third of the Delmarva farms have planted trees, technically known as vegetative environmental buffers. The idea offers a way to cut pollution, save money and energy, and make the neighbors happy.
小题1:The second paragraph mainly tells us ______.
A.planting trees as much as possible |
B.the advantages of trees |
C.how to reduce heating costs |
D.why trees are received |
A.plant | B.smell | C.height | D.water |
A.trees | B.tunnel fans | C.windows | D.poles |
A.three rows of trees are really good to the environment |
B.researches began to realize the problem in 2000 |
C.most farmers show interest in planting trees |
D.the trees growing quickly can be cut off in a few years |
Now,it’s important for the managers in a company to understand what their customers want if they are going to develop effective marketing strategies(策略).There are various ways of doing this.One way at supermarkets(超市),for example,is to interview(采访)customers while they’re doing their shopping.They can be asked what they prefer to buy and then the results of the research can be studied.This provides information on which to base future marketing strategies.It’s also quite normal for top managers from department stores to spend a day or two each month visiting stores and mixing freely with the public,as if they were ordinary customers,to get an idea of how customers act.
Another way to get information from customers is to give them something.For example,some fast food restaurants give away tickets in magazines or on the street that permit customers to get part of their meal for nothing.As well as being a good way of attracting customers into the restaurants to spend their money,it also allows the managers to get a feel for where to attract customers and which age-groups to attract.
Another strategy used at some well-known parks such as Disneyland is for top managers to spend at least one day in their work,touring the park dressed as Mickey Mouse or something like that.This provides them with a perfect chance to examine the scene and watch the customers without being noticed.
小题1:The text is designed for ________.
A.managers | B.salesmen |
C.researchers | D.customers |
A.Visiting customers themselves. |
B.Giving customers free food on the street. |
C.Visiting parks as ordinary customers. |
D.Asking customers questions at supermarkets. |
A.Visiting Disneyland. |
B.Wearing attractive clothes. |
C.Acting Mickey Mouse. |
D.Dressing up and walking around. |
A.how to do market research |
B.how to develop marketing strategies |
C.how to find out customers’ social needs |
D.how to encourage customers to spend more money |
Many of these wage-earners return in the end.In the meantime,they send home huge amounts of money—in the Philippines’ case,over 10% of its GDP.Between January and November,the amount was up 18% on the same period of 2005.Poverty and unemployment are still high in the Philippines and other labour-exporting(劳务输出) countries.They would be far worse but for this outflow of bodies and inflow of dollars.As for those Asian countries that import(输入) labour,as in Europe,falling birth rates mean they are going to need more foreign workers.
On January 13th leaders of the Association of Southeast Asian Nations(ASEAN) signed an agreement to help migrant(流动的) workers—with the realization that the flow of labour between their countries is a growing problem that they cannot blame on outsiders.A 2005 study showed that 8.4 million Southeast Asians worked outside their home countries,but this did not include the huge numbers of Indonesians doing so without papers.So the true total is probably rather higher.
Of the ten ASEAN countries,the Philippines,Indonesia,Myanmar,Cambodia,Vietnam and Laos export labour,Singapore and Brunei import it,and Thailand and Malaysia do both.Sziraczki of the UN’s International Labour Organization points out that,in the next ten years,the total labour force of the worker-exporting countries should grow by about a third.It makes sense to work on the problem before it gets out of control.
People in the receiving countries seem to be worried about competition for their jobs.Most Thais said their government should admit(准入) no more foreign workers,and a few thought otherwise.Even in Singapore,just over half of people are against admitting more foreign workers.Malaysians think that the increase in foreign workers has worsened crime rates(犯罪率).
小题1:It can be inferred from the case of the Philippines that______.
A.the country is Asia’s main source of migrant workers |
B.labour exports lead to a 10% growth of its GDP |
C.the outflow of labour helps solve its social problems |
D.the country both exports and imports labour force |
A.there is a greater flow of labour than reported |
B.more Indonesians work abroad without papers |
C.some countries suffer from low birth rates |
D.the ASEAN is against admitting foreign workers |
A.higher birth rates |
B.lower crime rates |
C.greater money inflows |
D.stronger job competition |
A.support the flow of labour between countries |
B.report fairly on the question of labour flow |
C.express his worries over the ASEAN’s decision |
D.regard the outflow of labour as a serious problem |
The woman standing in cashier Jeffrey Kandt’s line seemed to be living on the edge of subsistence(生计). Her clothes were worn and her hands were those of a person who’d worked hard for what she had. She held a single item in her arms as she patiently waited to move to the front of the line — a Sony CD player. She had saved all year for this. With tax, the total would be close to $ 220.
As the woman got close to the cashier, she suddenly shouted, “Where’s my money? All of my money fro my son’s gift! Oh no!”
“Why my line?” Kandt thought as he watched the poor woman searching through her clothes. He was going to have to call his manager to avoid the sale but it would mean a long wait for the customers behind her. “I am going to go home late tonight,” Kandt thought.
Then an amazing thing happened. At the back of the line, a man took out his wallet, pulled out $100 and passed it forward. As the cash moved up the line, a twen5ty-dollar bill was added here, and a ten-dollar bill was added there. When the collection finally reached the registewr, Kandt counted $ 220.
Strangers had fulfilled a poor woman’s Christmas wish.
The poor in his line at the Wal-Mart in Cleburne, Texas, had come together on Christmas Eve, 2002.
小题1:According to the passage, the woman’s Christmas wish was to ______.
A.collect $ 220 for her family | B.buy her son a CD player as a gift |
C.buy enough food for her family | D.organize a big party for her son |
A.He was impatient and wanted to go home. |
B.He wanted to see whether the woman had money or not. |
C.He wanted the woman to stand in another line. |
D.He didn’t think about the customers waiting behind the woman. |
A.a description of a man standing in the line |
B.the cashier, Jeffery Kandt |
C.the collection of $ 220 |
D.a reason why the strangers collected he money |
A.The woman collected money by herself. |
B.The woman seemed to be poor, but in fact had lots of money. |
C.Strangers in the line volunteered to help the woman. |
D.The woman had never ay money. |
A.H.M. Farook, UNICEF"s operations area officer for China and Mongolia said, “China can be very satisfied to tell the whole world what can be done with limited resources to help its children to grow healthily and happily.”
China"s child population makes up one fifth of the world"s total.
“The reason behind the remarkable achievement is China"s long tradition of caring for children both at home and in society," he said.
“What"s more is that Chinese people have always given special attention to children who are in special need."
The UN official made the remarks when addressing a group of 50 children and staff from the Beijing Children"s Welfare Home at the Shangri la Hotel, Beijing.
The hotel invited the orphans to share snacks(小吃), sing, dance and play games at a park inside the hotel for a “Share the Sunshine" party, as a prelude(前奏) to celebrations to mark the Children’s Day.
The Beijing children"s Welfare Home, set up soon after New China was founded in 1949, has at present more than 400 children.
A leading official of the welfare institution said that the children live a happy life and that the agency spends 400-500 yuan a month for an average orphan. An average Chinese worker earned 440 yuan a month during the first quarter this year.
Gu Xiaojin, deputy secretary general of the China Youth Development Foundation (CYDF), said people from all walks of like have contributed to the welfare of the Chinese children.
She said that CYDF set up the Project Hope in 1989, which walls on people across the country to donate money to help poor children to continue their schooling.
By the end of last year, she said, CYDF had collected nearly 700 million yuan in donations, which has helped the establishment(建立) of 2,074 Hope primary schools and enabled more than 1.25 million dropouts to return to school classrooms.
小题1:According to the passage, how can children grow healthily and happily?
A.They are offered best education and satisfying life. |
B.They must have their own parents who are rich. |
C.Both the society and their parents care for them. |
D.They are allowed to take part in many activities like computer games as often as possible. |
A.1,920,000 | B.700,000 | C.874,000 | D.900,000 |
A.China"s population makes up one fifth of the world"s total. |
B.The CYDE has used the money to help reduce dropouts. |
C.The Beijing children"s Welfare Home was founded in 1989. |
D.An average Chinese worker earned 440 yuan during the first quarter this year. |
A.There are many children’s welfare homes. |
B.The Hope Project has been very successful. |
C.The Chinese governments have been working harder than before. |
D.China has a long tradition of caring for children both at home and in society. |
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