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[主观题]

For as long as humans have raised crops as a source of food and other products, insects ha

ve damaged them. Between 1870 and 1880, locusts ate millions of dollars' worth of crops in the Mississippi Valley. Today in the United States the cotton boll weevil damages about 300 million dollars' worth of crops each year. Additional millions are lost each year to the appetites of other plant-eating insects. Some of these are corn borers, gypsy moths, potato beetles, and Japanese beetles. In modern times, many powerful insecticides(杀虫剂) have been used in an attempt to destroy insects that damage crops and trees. Some kinds of insecticides, when carefully used, have worked well. Yet the same insecticides have caused some unexpected problems. In one large area, an insecticide was used against Japanese beetles, which eat almost any kind of flower or leaf. Shortly afterward, the number of corn borers almost doubled. As intended, the insecticide had killed many Japanese beetles. But it had killed many of the insect enemies of the corn borer as well. In another case, an insecticide was used in Louisiana to kill the troublesome fire ant. The insecticide did not kill many fire ants. It did kill several small animals. It also killed some insect enemies of the sugarcane borer, a much more destructive pest than the fire ants. As a result, the number of sugarcane borers increased and severely damaged the sugarcane crop. To be sure that one insect pest will not be traded for another when an insecticide is used, scientists must perform careful experiments and do wide research. The experiments and research provide knowledge of the possible hazards an insecticide may bring to plant and animal communities. Without such knowledge, we have found that nature sometimes responds to insecticides in unexpected ways. An insecticide was used in Louisiana to kill the troublesome______.

A.corn borer

B.Japanese beetle

C.gypsy moth

D.fire ant

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发布时间：2023-06-16

更多“For as long as humans have raised crops as a source of food and other products, insects ha”相关的问题

第1题

Which of the following definitions of society is true()

A、Society is the sum of the relationships formed by living things and the environment

B、Human production, consumption, entertainment, politics, education, etc, all belong to the scope of social activities

C、Society refers to the organisms living together in a specific environment, which can be maintained for a long time and cannot be separated from each other. It is a kind of structure that cannot be easily changed

D、Society is a collection of individuals who live together united through a variety of relationships

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第2题

Water is the most important of all the things we eat and ___1___. Not many people und

erstand this, but it's quite ___2___. The human body can go without food for a long time, yet two or three days without water can usually make people die.

Many people don't know how ___3___ water the human body needs to work well, and many people do not drink enough,___4___in hot weather. Our body is mostly water about 67%--75%. If we don't have enough, we'll feel ___5___ and many will get ill. So, you know, how important the water is to us all.

1)、A.much

B.tired

C.even

D.true

E.drink

2)、A.much

B.tired

C.even

D.true

E.drink

3)、A.much

B.tired

C.even

D.true

E.drink

4)、A.much

B.tired

C.even

D.true

E.drink

5)、A.much

B.tired

C.even

D.true

E.drink

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第3题

根据以下内容回答题：Let US take a look at the chief thing in the story—the human body itsel

根据以下内容回答题：

Let US take a look at the chief thing in the story—the human body itself．A human body appears to be rather soft and delicate，compared with that of a wild animal，but it is actually surprisingly strong．Indeed，its very softness and looseness are an advantage；it makes man good at moving about and falling about in safety．Man is the most skillful in movement of all living things of his own size，because he can do so many different things with his limbs．Man’s games show how he can control his own body．No other land creature can swim as skillfully as man；none has such varied grace；very few live as long as he；none is so strong in its natural resistance to disease．Therefore man has a great advantage in his battle against the risks of damage and death that threaten him．It is difficult to kill him as long as he is fed and in good health．Yet every day thousands of people die needlessly，even though man is naturally strong，because of those two killers，disease and starvation，with the battle．

Old age？No one can live forever，so one might’suppose that quite a large number of oldpeople would come to the end of their days every year．There is，however，another thing to re-member．During the time it has taken you to read this page，a considerable number of babies have been born somewhere in the wodd—one is born every one and a quarter seconds!Of these babies，one group can be expected to have a good long life of about seventy years，because they were lucky enough to be born in countries where living standards are high．

The deadliest of all killers are starvation and disease．We cannot be content until we have mastered them．To do so is one of the most important tasks of our times．

The softness and looseness of man’s body are an advantage because it__________ ．查看材料

A.makes him strong

B.makes him resistant to diseases

C.helps him to avoid injury

D.keeps him in good health

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第4题

Visitors from space may have landed on our planet dozens, even hundreds of times during th

e long, empty ages while Man was still a dream of the distant future. Indeed, they could have landed on 90 percent of the earth as recently as two or three hundred years ago, and we could never have heard of it. If one searches through old newspapers and local records, one can find many reports of strange incidents that could be interpreted as visits from outer space. A stimulating writer, Charles Fort, has made a collection of UFO sighting in his book! One is tempted to believe them more than any modern reports, for the simple reason that they happened long before anyone had ever thought of space travel. Yet at the same time, one can't take them too seriously, for before scientific education was widespread, even sightings of meteors, comets, auroras, and so on, gave rise to the most incredible stories, as they still do today.

According to the passage, visitors from space may have landed on the earth ______.

A．long before man had dreamed of it

B．long before there were human beings

C．in the last few hundred years

D．after the space age began

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第5题

Questionsare based on the following passage. When you think about the growth of human popu

Questionsare based on the following passage.

When you think about the growth of human population over the last century or so， it is alltoo easy to imagine it merely as an increase in the number of humans. But as we（36）， so doall the things associated with us，（37）our livestock （家畜）. At present， there are about 1.5 bil-lion cattle and domestic buffalo and about 1.7 billion sheep and goats. With pigs and poultry，they form. a（38）part of our enormous biological footprint upon this planet.

Just how enormous was not really apparent until the（39）of a new report， called "Live-stock"s Long Shadow，" by the Food and Agriculture Organisation of the United Nations.

Consider these numbers. Global livestock grazing （放牧） and feed production use "30percent of the land surface of the planet." Livestock —— which consume more food thanthey（40）—— also compete directly with humans for water. And the drive to expand grazingland destroys more biologically sensitive terrain， rain forests（41）， than anything else.

But what is even more striking， and alarming， is that livestock are（42）for about 18 per-cent of the global warming effect， more than transportation"s（43）. The culprits （罪魁祸首）are methane —— the natural result of bovine digestion —— and the nitrogen emitted by manure.

Deforestation of grazing land adds to the effect.

There are no easy trade-offs when it comes to global warming —— such as cutting back oncattle to make room for cars. The human（44）for meat is certainly not about to end anytimesoon. As "Livestock"s Long Shadow" makes clear， our health and the health of the planet de-pend on pushing livestock production in more（45）directions.

A．publication

B．waste

C．contribution

D．certainly

E. yield

F. multiply

G. critical

H. passion

I . concerning

J . available

K. liable

L. sustainable

K. responsible

N. including

O.especially

第（36）题应填__________

查看材料

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第6题

（41~45) Researchers have found that drugs used to treat human seizures can delay aging in

(41~45) Researchers have found that drugs used to treat human seizures can delay aging in worms by as much as 50 percent. The roundworms used for the study are similar to humans in their molecular makeup, raising the

possibility that the drugs could also extend the life span of humans。

第41题：“By finding a class of drugs that delays aging we have found a relationship between the function of the nervous system and aging that was not well understood, ” said Kerry Komfeld, a geneticist at the Washington University School of Medicine in St. Louis, Missouri. The findings are detailed this week in the journal Science。 The discovery came out of the thesis work by one of Komfeld’s graduate students, Kimberley Evason. About four years ago, Evason began exposing groups of the roundworm Caenorhabditis elegans to commercially available drugs to see if the drugs would delay aging or promote longevity。

A. But Komfeld said scientists will not know about the applicability of the drugs in humans until a similar study is done on humans. “What’s very encouraging is that these drugs were developed to treat humans, and they are well understood, because they’ve been used for a long time, ” he said。

B. Later the scientists discovered that two related anticonvulsant drugs also lengthened the lives of the worms-in the case of one drug, by almost 50 percent. “This was a big surprise to use, Komfeld said. ”“We didn’t think anticonvulsant drugs had any particular relationship to aging. That connection was completely unexpected. ”

C. Roundworms are a poor subject for experiments, because they are not like humans, even though their molecules are similar. For example, they have no bones, nor do they show emotions, making it difficult to know how exactly human subjects would react to these drugs in large quantities. However, using the worms allows experiments to be conducted quickly, because they do not live for long。

D. “Somehow the neural activity seems to regulate the aging of all of the body the skin, musculature, and reproductive tract, ” Kornfeld said. “Somehow the nervous system coordinates the progress of all these tissues, evidently, though the life stages. But we don’t know how it does that. ”

E. The discovery may also shed light on the little-understood aging process. Since the drugs act on the neuromuscular systems of both humans and worms, the findings hint at a link between neural activity and aging。

F. Unlike vertebrates, the worms are ideal subjects for the study of aging because of their short life spans, which last only a couple of weeks in a laboratory. The worm is well known in genetics, and the worm’s genome has been sequenced。

G. Use of this drug has been permitted by law since 1998 and wider use is now expected as a result of the studies. “We can clearly link this drug with human aging, but we still need to find proof, says Kornfeld optimistically. ”

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第7题

There may also be other targets not yet explored that affect aging and neuromuscul

ar function. Said Kornfeld: “The process of aging remains mysterious. ”

A. But Komfeld said scientists will not know about the applicability of the drugs in humans until a similar study is done on humans. “What’s very encouraging is that these drugs were developed to treat humans, and they are well understood, because they’ve been used for a long time, ” he said。

B. Later the scientists discovered that two related anticonvulsant drugs also lengthened the lives of the worms-in the case of one drug, by almost 50 percent. “This was a big surprise to use, Komfeld said. ”“We didn’t think anticonvulsant drugs had any particular relationship to aging. That connection was completely unexpected. ”

C. Roundworms are a poor subject for experiments, because they are not like humans, even though their molecules are similar. For example, they have no bones, nor do they show emotions, making it difficult to know how exactly human subjects would react to these drugs in large quantities. However, using the worms allows experiments to be conducted quickly, because they do not live for long。

D. “Somehow the neural activity seems to regulate the aging of all of the body the skin, musculature, and reproductive tract, ” Kornfeld said. “Somehow the nervous system coordinates the progress of all these tissues, evidently, though the life stages. But we don’t know how it does that. ”

E. The discovery may also shed light on the little-understood aging process. Since the drugs act on the neuromuscular systems of both humans and worms, the findings hint at a link between neural activity and aging。

F. Unlike vertebrates, the worms are ideal subjects for the study of aging because of their short life spans, which last only a couple of weeks in a laboratory. The worm is well known in genetics, and the worm’s genome has been sequenced。

G. Use of this drug has been permitted by law since 1998 and wider use is now expected as a result of the studies. “We can clearly link this drug with human aging, but we still need to find proof, says Kornfeld optimistically. ”

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第8题

Is there something as truth？ For a good many centuries "the search for truth" has been【31】

the noblest activity of the human mind, but the seekers after truth have come to such【32】conclusions that it often seems that very little progress has been made.【33】,there are many people who reel that we are actually going backward. They【34】, often contemptuously, that we have accumulated more "knowledge" than our ancestors, but they think we are farther from the truth than ever, or even that we have【35】the truth that we once possessed.

If people look for anything long enough without finding it, the question naturally arises【36】the thing is really there to find. You have seen a picture of an animal with a lion's head, a goat's body, and a serpent's tail—and maybe an eagle's wings for good【37】. There is plenty of evidence that each part of this animal【38】—but there is no【39】evidence that the parts ever occur in this combination. It is at least conceivable that the seekers after "truth" have made a similar mistake and invented an【40】combination.

(31)

A．regarded

B．considered

C．pondered

D．referred

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第9题

People have wondered for a long time how their personalities and behaviors are formed. It

is not easy to explain why one person is intelligent and another is not, or why one is cooperative and another is competitive.

Social scientists are, of course, extremely interested in these types of questions. They want to explain why we possess certain characteristics and exhibit certain behaviors. There are no clear answers yet, but two distinct schools of thought on the matter have been developed. As one might expect, the two approaches are very different from one another, and there is a great deal of debate between proponents of each theory. The controversy is often referred to as " nature/nurture".

Two who support the" nature" side of the conflict believe that our personalities and behavior. patterns are largely determined by biological and genetic factors. That our environment has little, if anything, to do with our abilities, characteristics, and behavior. is central to this theory. Taken to an extreme, this theory maintains that our behavior. is predetermined to such a degree that we are almost completely governed by our instincts.

Proponents of the " nurture" theory, or as they are often called, behaviorists, claimed that our environment is more important than our biologically based instincts in determining how we will act. A behaviorist, B. F. Skinner, sees humans as beings whose behavior. is almost completely shaped by their surroundings. The behaviorists view of the human being is quite mechanistic; they maintain that, like machines, humans respond to environmental stimulus as the basis of their behavior.

Neither of these theories can yet fully explain human behavior. In fact, it is quite likely that the key to our behavior. lies somewhere between these two extremes. That the controversy will continue for a long time is certain.

Which of the following statements would supporters of the" nature" theory agree with？

A．A person's instincts have little effect on his actions.

B．Environment is important in determining a person's behavior. and personality.

C．Biological reasons have a strong influence on how we act.

D．The behaviorists' view correctly explains how we act.

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第10题

Is there something as truth？ For a good many centuries "the search for truth" has been （31

Is there something as truth？ For a good many centuries "the search for truth" has been (31) the noblest activity of the human mind, but the seekers after truth have come to such (32) conclusions that it often seems that very little progress has been made. (33) , there are many people who reel that we are actually going backward. They (34) , often contemptuously, that we have accumulated more "knowledge" than our ancestors, but they think we are farther from the truth than ever, or even that we have (35) the truth that we once possessed. If people look for anything long enough without finding it, the question naturally arises (36) the thing is really there to find. You have seen a picture of an animal with a lion's head, a goat's body, and a serpent's tail--and maybe an eagle's wings for good (37) There is plenty of evidence that each part of this animal (38) --but there is no (39) evidence that the parts ever occur in this combination. It is at least conceivable that the seekers after "truth" have made a similar mistake and invented an (40) combination.A.regardedB.consideredC.ponderedD.referred

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第11题

Over eight months the scientists tested 20 drugs, all with negative results. Finall

y they tested the anticonvulsant drug ethosuzimide. Researchers found that the drug extended the life span of roundworms from 16. 7 days to 19. 6 days, a 17 percent increase。

A. But Komfeld said scientists will not know about the applicability of the drugs in humans until a similar study is done on humans. “What’s very encouraging is that these drugs were developed to treat humans, and they are well understood, because they’ve been used for a long time, ” he said。

B. Later the scientists discovered that two related anticonvulsant drugs also lengthened the lives of the worms-in the case of one drug, by almost 50 percent. “This was a big surprise to use, Komfeld said. ”“We didn’t think anticonvulsant drugs had any particular relationship to aging. That connection was completely unexpected. ”

C. Roundworms are a poor subject for experiments, because they are not like humans, even though their molecules are similar. For example, they have no bones, nor do they show emotions, making it difficult to know how exactly human subjects would react to these drugs in large quantities. However, using the worms allows experiments to be conducted quickly, because they do not live for long。

D. “Somehow the neural activity seems to regulate the aging of all of the body the skin, musculature, and reproductive tract, ” Kornfeld said. “Somehow the nervous system coordinates the progress of all these tissues, evidently, though the life stages. But we don’t know how it does that. ”

E. The discovery may also shed light on the little-understood aging process. Since the drugs act on the neuromuscular systems of both humans and worms, the findings hint at a link between neural activity and aging。

F. Unlike vertebrates, the worms are ideal subjects for the study of aging because of their short life spans, which last only a couple of weeks in a laboratory. The worm is well known in genetics, and the worm’s genome has been sequenced。

G. Use of this drug has been permitted by law since 1998 and wider use is now expected as a result of the studies. “We can clearly link this drug with human aging, but we still need to find proof, says Kornfeld optimistically. ”

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