Even plants can run a fever, especially when they are under attack by insects or disease.B - 试题答案网问答

第1题

Even plants can run a fever, especially when they're under attack by insects or disease. B

ut unlike humans, plants can have their temperature taken from 3, 000 feet away-straight up. A decade ago, adapting the infrared scanning technology developed for military purposes and other satellites, physicist Stephen Paley came up with a quick way to take the temperature of crops to determine which ones are under stress. The goal was to let farmers precisely target pesticide spraying rather than rain poison on a whole field, which invariably includes plants that don't have pest problems.

Even better, Paley's Remote Scanning Services Company could detect crop problems before they became visible to the eye. Mounted on a plane flown at 3, 000 feet at night, an infrared scanner measured the heat emitted by crops. The data were transformed into a color-coded map showing where plants were running" fevers". Farmers could then spot-spray, using 50 to 70 percent less pesticide than they otherwise would.

The bad news is that Paley's company closed down in 1984, after only three years. Farmers resisted the new technology and long-term backers were hard to find. But with the renewed concern about pesticides on produce, and refinements in infrared scanning, Paley hopes to get back into operation. Agriculture experts have no doubt the technology works. "This technique can be used on 75 percent of agricultural land in the United States, "says George Oerther of Texas A&M. Ray Jack son ,who recently retired from the Department of Agriculture, thinks remote infrared crop scanning could be adopted by the end of the decade. But only if Paley finds the financial backing which he failed to obtain 10 years ago.

Plants will emit an increased amount of heat when they are ______.

A．sprayed with pesticides

B．facing an infrared scanner

C．in poor physical condition

D．exposed to excessive sun rays

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第2题

Even plants can run a fever, especially when they' re under attack by insects or disease.

But unlike humans, plants can have their temperature taken from 3,000 feet away—straight up. A decade ago, adapting the infrared(红外线) scanning technology developed for military purposes and other satellites, physicist Stephen Paley came up with a quick way to take the temperature of crops to determine which ones are under stress. The goal was to let farmers precisely target pesticide(杀虫剂) spraying rather than rain poison on a whole field, which invariably includes plants that don't have pest(害虫) problems.

Even better, Paley's Remote Scanning Services Company could detect crop problems before they became visible to the eye. Mounted on a plane flown at 3,000 feet at night, an infrared scanner measured the heat emitted by crops. The data Were transformed into a color-coded map showing where plants were running "fevers". Farmers could then spot-spray, using 50 to 70 percent less pesticide than they otherwise would.

The bad news is that Paley' s company closed down in 1984, after only three years. Farmers resisted the new technology and long-term backers were hard to find. But with the renewed concern about pesticides on produce, and refinements in infrared scanning, Paley hopes to get back into operation. Agriculture experts have no doubt the technology works. "This technique can be used on 75 percent of agricultural land in the United States," says George Oerther of Texas A&M. Ray Jackson, who recently retired from the Department of Agriculture, thinks remote infrared crop scanning could be adopted by the end of the decade. But only if Paley finds the financial backing which he failed to obtain 10 years ago.

Plants will emit an increased amount of heat when they are in poor physical condition.

A．Right

B．Wrong

C．Not mentioned

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第3题

听力原文：A computer is a machine designed to perform. work mathematically and to store and

听力原文： A computer is a machine designed to perform. work mathematically and to store and select information that has been fed into it. It is run by either mechanical or electronic means. These machines can do a great deal of complicated work in a very short time. A large computer, for example, can add or subtract nine thousand times a second, multiply a thousand times a second, or divide five hundred times a second. Its percentage of error is about one in a billion digits. It has been estimated that human beings making calculations average about one mistake per two hundred digits.

The heart of an electronic computer lies in its vacuum tubes, or transistors. Its electronic circuits work a thousand times faster than the nerve cells in the human brain. A problem that might take a human being two years to solve can be solved by a computer in one minute, but in order to work properly, a computer must be given instructions--it must be programmed.

Computers can be designed for many specialized purposes--they can be used to prepare payrolls, guide airplane flights, direct traffic, even to play chess. Computers play an essential role in modern automation in many plants and factories throughout the world.

(33)

A．One in a billion digits.

B．Zero.

C．One mistake per two hundred digits.

D．One in a million digits.

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第4题

Passage Four:Questions 26 to 30 are based on the following passage.Even plants can run a f

ever, especially when they’re under attack by insects or disease. But unlike humans, plants can have their temperature taken from 3,000 feet away-straight up. A decade ago, adapting the infrared (红外线) scanning technology developed for military purposes and other satellites, physicist Stephen Paley came up with a quick way to take the temperature of crops to determine which ones are under stress. The goal was to let farmers precisely target pesticide (杀虫剂) spraying rather than rain poison on a whole field, which invariably includes plants that don’t have pest (害虫) problems.

Even better, Paley’s Remote Scanning Services Company could detect crop problems before they became visible to the eye. Mounted on a plane flown at 3,000 feet at night, an infrared scanner measured the heat emitted by crops. The data were transformed into a color-coded map showing where plants were running “fevers”. Farmers could then spot-spray, using 50 to 70 percent less pesticide than they otherwise would.

The bad news is that Paley’s company closed down in 1984, after only three years. Farmers resisted the new technology and long-term backers were hard to find. But with the renewed concern about pesticides on produce, and refinements in infrared scanning, Paley hopes to get back into operation. Agriculture experts have no doubt the technology works. “This technique can be used on 75 percent of agricultural land in the United States,” says George Oerther of Texas A&M. Ray Jackson, who recently retired from the Department of Agriculture, thinks remote infrared crop scanning could be adopted by the end of the decade. But only if Paley finds the financial backing which he failed to obtain 10 years ago.

第26题：Plants will emit an increased amount of heat when they are ________.

A) sprayed with pesticides

B) facing an infrared scanner

C) in poor physical condition

D) exposed to excessive sun rays

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第5题

根据短文回答 46～50 题。 The Roadrunner The roadrunner（走雀)lives in the desert zone o

根据短文回答 46～50 题。

The Roadrunner

The roadrunner(走雀)lives in the desert zone of the southwestern United States and northern Mexico.___________ (46)People gave it its name because they Usually see it running across a road,but of course,it spends more time among the plants of the desert than it does on roads.

The roadrunner is quite a large bird-about 45 centimeters long and 25 centimeters high.___________(47)It holds its head straight out in front and its tail sticks straight。Out in back.It takes long steps and can run 30 kilometers an hour.

It eats an amazing variety of food.Although it eats plants once in a while,it is mostly a meat eater.Most of its diet is insects,but it also catches birds,mice。and other smile animals.It is even brave enough to catch snakes and black widow spiders(蜘蛛) ___________ (48)When he finds one,he gives her presents-a snake to eat or a tiny branch of a tree to use in building a nest.Then they build their nest,the female lays eggs,and they raise their young.

___________ (49) one couple in Arizona feeds a pair of roadrunner that come once at a time every day and make a noise outside the window.If Someone doesn't give the bird a piece of hamburger immediately, the bird knocks on the window with its beak (喙).Roadrunners are not shy.

___________ (50)They will stand on a chair or table and watch television and they seem really interested in what is happening on the program.（）

A．Roadrunners can also become friendly with people.

B．People laugh when it runs because it looks so funny.

C．It is a bird,but it can only fly about as much as a chicken can.

D．In early spring.the bird doesn't eat anything.

E．Another couple feeds a pair of roadrunners that go right into the house.

F．In the spring,a male roadrunner begins looking for a female as a mate.

第 46 题请选择（46）处的最佳答案

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第6题

Scientists are trying to make the deserts into good land again. They want to bring water t

o the deserts, so people can live and grow food. They are learning a lot about the deserts. But more and more of the earth is becoming desert all the time. Scientists may not be able to change the desert. Scientists think that people make deserts. People are doing bad things to the earth.

Some places on the earth don't get very much rain. But they still don't become deserts. This is because some green plants are growing there. Small green plants and grass are very important to dry places. Plants don't let the hot sun make the earth even drier. Plants don't let the wind blow the dirt(土)away. When a little bit of rain falls, the plants hold the water. Without plants, the land can become a desert much more easily.

Deserts ______.

A．get very little rain

B．never have any plants or animals in them

C．can all be turned into good land before long

D．both A and C

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第7题

Climate, more than any other single factor: determines the distributions of life on Earth.

Climatic boundaries establish the limits within which organisms can survive.

Plants, even more than animals, must be well adapted to climate in order to survive. They cannot move about or take shelter but must be equipped to endure whatever weather conditions are likely to occur.

In the harsh conditions of tundra, for example, low growing mosses, lichens, and a few flowering plants all hug the ground for shelter from icy winds.

Animals, despite their ability to move about and find shelters, are just as much influenced by climate as plants are. Creatures such as the camel and the penguin are so highly specialized that they have as extremely limited distribution. Others, such as bears, are flexible enough to adapt to a broad range of climates. Oceandwelling organisms are just as sensitive to climatic changes—in this case temperature and salinity (含盐量)—as land animals. Reef corals can survive only in clear warm seawater. Certain foraminifers are so sensitive to changes in their environment that their presence can be taken as an index of sea temperature. Human beings are among the least specialized of all animals and can live almost anywhere. Their clothes and their homes act as a sort of "miniature climate" that can be taken with them everywhere.

Which of the following is neither plant nor animal？

A．Tundra

B．Reef coral

C．Penguin

D．Camel

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第8题

Scientists have known for some time that certain plants, called hyperaccumu-lators, can co

ncentrate minerals at levels a hundredfold or greater than normal. A survey of known hyperaccumulators identified that 75 percent of them amassed nickel; cobalt, copper, zinc, manganese, lead, and cadmium are other minerals of choice. Hyperaccumulators run the entire range of the plant world. They may be herbs, shrubs, or trees. Many members of the mustard family, spurge family, legume family, and grass family are top hyperaccumulators. Many are found in tropical and subtropical areas of the world, where accumulation of high concentrations of metals may afford some protection against plant-eating insects and microbial pathogens.

Why does the author mention "herbs," "shrubs," and "trees"？

A．To provide examples of plant types that cannot tolerate high levels of harmful minerals

B．To show why so many plants are hyperaccumulators

C．To help explain why hyperaccumulators can be found in so many different places

D．To emphasize that hyperaccumulators occur in a wide range of plant types

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第9题

Nearly any kind of plant of the forest understory can be part of a deers diet. Where the f

orest inhibits the growth of grass and other meadow plants, the black-tailed deer browses on huckleberry, salal, dogwood, and almost any other shrub or herb. But this is fair-weather feeding. What keeps the black-tailed deer alive in the harsher seasons of plant decay and dormancy？ One compensation for not hibernating is the built-in urge to migrate. Deer may move from high-elevation browse areas in summer down to the lowland areas in late fall. Even with snow on the ground, the high bushy understory is exposed; also snow and wind bring down leafy branches of cedar, hemlock, red alder, and other arboreal fodder.

It can be inferred from the discussion in paragraph 2 that winter conditions

A．cause some deer to hibernate

B．make food unavailable in the highlands for deer

C．make it easier for deer to locate understory plants

D．prevent deer from migrating during the winter

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第10题

Climate, more than any other single factor, determines the distribution of life on Earth.

Climatic boundaries establish the limits within which organisms can survive. Plants, even more than animals, must be well adapted to climate in order to survive. They cannot move about or take shelter but must be equipped to endure whatever weather conditions are likely to occur. In the harsh conditions of the tundra (苔原), for example, low growing mosses, lichens, and a few flowering plants all hug the ground for shelter from icy winds.

Animals, despite their ability to move about and find shelter, are just as much influenced by climate as plants are. Creatures such as the camel and the penguin are so highly specialized that they have an extremely limited distribution. Others, such as bears, are flexible enough to adapt to a broad range of climates. Ocean-dwelling organisms are just as sensitive to climatic changes-- in this case temperature and salinity—as land animals. Reef corals (珊瑚) can survive only in clear warm seawater. Certain foraminifers are so sensitive to changes in their environment that their presence can be taken as an index of sea temperature. Human beings are among the least specialized of all animals and can bye almost anywhere. Their clothes and their homes act as a sort of "miniature climate" that can be taken with them everywhere.

According to the passage, plants on the tundra grow in the ground______.

A．to avoid being eaten by arctic animals

B．because fertilizer is not readily available

C．to minimize exposure to the cold

D．because unfrozen water supplies are very scarce

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