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Many species are in peril of extinction because of our destruction of their natural ____.
A.habitat
B.favor
C.hoop
D.circle
B.favor
C.hoop
D.circle
参考答案
参考解析
解析：本题考查词语意思。题目意为“许多物种由于我们破坏了它们的自然栖息地，现在正面临灭绝的危险。”A项意为“栖息地”。B项意为“帮助、袒护”。C项意为“箍、铁环”。D项意为“圈子、循环”。因此选A项，破坏了它们的自然栖息地。
更多 “Many species are in peril of extinction because of our destruction of their natural ____. A.habitat B.favor C.hoop D.circle” 相关考题
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"Hidden" Species May Be Surprisingly CommonCryptic species animals that appear identical but are genetically quite distant—may be much more widespread than previously thought. The findings could have major implications in areas ranging from biodiversity estimates and wildlife management, to our understanding of infectious diseases and evolution.Reports of cryptic species have increased dramatically over the past two decades with the advent of relatively inexpensive DNA sequencing technology. Markus Pfenninger and Klaus Schwenk, of the Goethe-Universitat, in Frankfurt, Germany, analyzed all known data on cryptic animal species and discovered that they are found in equal proportions throughout all major branches of the animal kingdom and occur in equal numbers in all biogeographieal regions.Scientists had previously speculated that cryptic species were predominantly found in insects and reptiles, and were more likely to occur in tropical rather than temperate regions. "Species that are seemingly widespread and abundant could in reality be many different cryptic species that have low populations and are highly endangered. " Says Pfenninger. Until the genetic information of all species in at least one taxon is thoroughly studied, no one will know just how many cryptic species exist. "It could be as high as 30%. " Pfenninger says."I'm extremely surprised by their results. " Says Alex Smith of the University of Guelph in Ontario, Canada. "It's a call to arms to keep doing the broad kind of genetic studies that we are doing. "Sampling as many individuals as possible, scientists hope to complete work on all fish and birds in another 5 to 10 years. Once either of these taxonomic groups is completed, Pfenninger says researchers will be able to decide how many cryptic species exist throughout the animal kingdom.Examples of cryptic species include the African elephant. A 2001 study found the elephants were actually two genetically distinct, non-interbreeding species, the African bush elephant and the African elephant. The species are currently listed as vulnerable and threatened, respectively, by the World Conservation Union (WCU).The reclassifications are more than an academic exercise. They define populations that have evolved independently of each other and whose genetic differences can have significant consequences. In the early 1900s misidentification of mosquito species based on morphology confused attempts to control malaria in Europe. Ultimately, what was thought to be a single species was actually made up of six sibling species, only three of which transmitted the disease. "The basic unit in biology is always the species, and you have to know what you are dealing with. " Pfenninger says. Much previous research is now no longer used, he says, because it is not clear what species was being studied.Which of the following about the significance of the research on cryptic species is NOT true?A．The results of the research can help the development of many other research areas.B．The results of the research can help the development of biodiversity estimates.C．The results of the research can help our understanding of infectious disease evolution.D．The results of the research can help our understanding of "survival of the fittest. "
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People are confused in their attempts to control malaria in Europe in the early 1900s, because scientists ______.A．identified only one mosquito species instead of six speciesB．thought only three mosquito species transmitted diseaseC．thought there was only one mosquito speciesD．did not know what species was being studied
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—Your bank is huge! It must have many departments.—()
A. It’s true. Our bank consists of many departments.B. Thank you, our bank is a small one.C. You are kidding! Our bank is a small one.
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Natural Living is the answer to several of our modern problems, especially the healthproblems.
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The loss of biological diversity has become most spectacularly noticeable in extinction or decline of populations of large and well-known animals.Many animal species have become extinct since the 1700’s, among them the California grizzly bear, the dodo, and the passenger pigeon.Hundreds of other animal species are threatened.In North America, endangered species include the black-footed ferret, the California condor, the desert tortoise, and the whooping crane.Most species in danger of extinction anywhere in the world are suffering from the intrusion (侵入) of human beings.The Asian elephant, for example, has become an endangered species due to the expansion of the human population throughout its range in southern Asia.In Africa, the African elephants are being killed off for their tusks.Monkeys and other primates throughout the world are threatened by hunting, capture for medical use, and the destruction of their habitats.And the rhinoceroses, lions, and other large mammals of the African savanna (grassy plains with scattered trees) compete for land and life with some of the most rapidly growing human populations in the world.The loss of biological diversity is most severe, however, in the tropical rain forests.The forests of the tropics are particularly vulnerable to disturbance because the soils have a low capacity for retaining nutrients.Most of the forests’ nutrient elements are held in the tissues of plants.When loggers and farmers destroy existing plant cover, the nutrients are washed from the land into streams, and the land itself becomes less able to support life.Destruction of these forests destroys the habitat of hundreds, sometimes thousands, of species from such creatures as the howler monkey and indigo macaw, to less visible species of plants, insects, and microbes, many of which are not yet known to science.1.The author points out that species extinction ().A.is most noticeable in North AmericaB.is mainly taking place among large animalsC.quickened with industrialization of the societyD.never took place before the 1700’s2.Which of the following is NOT mentioned with regard to human intrusion?A.Elephants are killed off for their tusksB.Some primates are hunted for medical useC.Growing human population results in the competition for land and life among animalsD.Men live increasingly on animals as their source of food.3.The chief cause of the gradual disappearance of biological diversity is ().A.human crueltyB.human interferenceC.the increase of human populationD.the disappearance of the forests4.In tropical forests，().A.animals live a hard life due to competitionB.a lot of species die out for lack of foodC.rains constitute the major threat to speciesD.a greater number of animals are yet to be known5.It can be inferred that species extinction ().A.proceeds of a faster rate than noticeableB.is the worst among well-known animalsC.is the most severe in AfricaD.is chiefly due to competition among species
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When contradicting the verbal messages, nonverbal messages tend to be morebelievable, because many of our nonverbal actions take place on a subconscious level.()
此题为判断题(对，错)。
考题
We are using up our natural resources too quickly and at the same time we are ______our environment with dangerous chemicals.A. protectingB. savingC. pollutingD. fighting
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Ecosystem1. The word “ecosystem” is short for ecological（生态的）system. An ecosystem is where living creatures expand within a given area. You can say that an ecosystem is the natural environment where biological organisms（生物）such as plants,animals and humans co-exist in this world. So naturally that includes you and me. Yes,we are all members of an ecosystem!2 .There are different kinds of ecosystems depending on the type of surface or environ-ment. Most are naturally made such as the ocean or lake and the desert or rainforest.Some are man-made or artificial to encourage co-habitation（同居）between living and non-living things in a monitored environment,such as a zoo or garden.3 .Plants make up the biggest group of biological creatures within an ecosystem,and that's because they are the natural food producers for everyone. Plants raised in the earth need air and collect sunlight to help them grow. When they grow,the plants and its fruits or flowers eventually become a source of food to animals,microorganisms（微生物）and even hu- mans,of course. Food is then converted to energy for the rest of us to function,and this hap-pens in a never-ending cycle until the living creatures die and break up back in the earth.4 .Ecosystems are the basis of survival for all living things.We depend on plants and ani-mals for food. In order for us to exist,we need to grow and care about other organisms. We also need to care for the non-living things within our environment like our air and water so we can continue living as a population. Since plants,animals and humans are all of various species（物种）,we all play a role in maintaining the ecosystem.5 .To preserve our ecosystems,we should stop using too much energy,which happens when we consume more than our share of resources. Humans should not disturb the natural habitat（栖息地）of plants and animals,and allow them to grow healthily for the cycle to con-tinue. Too many people in a habitat can mean displacement（搬迁）: imagine being thrown out of your home because there is no more space for everyone. Worse,overpopulation can also ru- in the environment and cause destruction of existing plants and animals.Paragraph 4_________A: What Can We Do to Help Protect Ecosystems?B: What Are Different types of Ecosystems?C: What Is an Ecosystem?D: What Destroys Ecosystems?E: How Does an Ecosystem Work?F: Why Are Ecosystems Emportant?
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Ecosystem1. The word “ecosystem” is short for ecological（生态的）system. An ecosystem is where living creatures expand within a given area. You can say that an ecosystem is the natural environment where biological organisms（生物）such as plants,animals and humans co-exist in this world. So naturally that includes you and me. Yes,we are all members of an ecosystem!2 .There are different kinds of ecosystems depending on the type of surface or environ-ment. Most are naturally made such as the ocean or lake and the desert or rainforest.Some are man-made or artificial to encourage co-habitation（同居）between living and non-living things in a monitored environment,such as a zoo or garden.3 .Plants make up the biggest group of biological creatures within an ecosystem,and that's because they are the natural food producers for everyone. Plants raised in the earth need air and collect sunlight to help them grow. When they grow,the plants and its fruits or flowers eventually become a source of food to animals,microorganisms（微生物）and even hu- mans,of course. Food is then converted to energy for the rest of us to function,and this hap-pens in a never-ending cycle until the living creatures die and break up back in the earth.4 .Ecosystems are the basis of survival for all living things.We depend on plants and ani-mals for food. In order for us to exist,we need to grow and care about other organisms. We also need to care for the non-living things within our environment like our air and water so we can continue living as a population. Since plants,animals and humans are all of various species（物种）,we all play a role in maintaining the ecosystem.5 .To preserve our ecosystems,we should stop using too much energy,which happens when we consume more than our share of resources. Humans should not disturb the natural habitat（栖息地）of plants and animals,and allow them to grow healthily for the cycle to con-tinue. Too many people in a habitat can mean displacement（搬迁）: imagine being thrown out of your home because there is no more space for everyone. Worse,overpopulation can also ru- in the environment and cause destruction of existing plants and animals.Plants are essential in an ecosystem because to other living creatures they are______.A: our share of resourcesB: a biological creatureC: a given areaD: the maintenance of the ecosystemE: the source of foodF: various species
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Ecosystem1. The word “ecosystem” is short for ecological（生态的）system. An ecosystem is where living creatures expand within a given area. You can say that an ecosystem is the natural environment where biological organisms（生物）such as plants,animals and humans co-exist in this world. So naturally that includes you and me. Yes,we are all members of an ecosystem!2 .There are different kinds of ecosystems depending on the type of surface or environ-ment. Most are naturally made such as the ocean or lake and the desert or rainforest.Some are man-made or artificial to encourage co-habitation（同居）between living and non-living things in a monitored environment,such as a zoo or garden.3 .Plants make up the biggest group of biological creatures within an ecosystem,and that's because they are the natural food producers for everyone. Plants raised in the earth need air and collect sunlight to help them grow. When they grow,the plants and its fruits or flowers eventually become a source of food to animals,microorganisms（微生物）and even hu- mans,of course. Food is then converted to energy for the rest of us to function,and this hap-pens in a never-ending cycle until the living creatures die and break up back in the earth.4 .Ecosystems are the basis of survival for all living things.We depend on plants and ani-mals for food. In order for us to exist,we need to grow and care about other organisms. We also need to care for the non-living things within our environment like our air and water so we can continue living as a population. Since plants,animals and humans are all of various species（物种）,we all play a role in maintaining the ecosystem.5 .To preserve our ecosystems,we should stop using too much energy,which happens when we consume more than our share of resources. Humans should not disturb the natural habitat（栖息地）of plants and animals,and allow them to grow healthily for the cycle to con-tinue. Too many people in a habitat can mean displacement（搬迁）: imagine being thrown out of your home because there is no more space for everyone. Worse,overpopulation can also ru- in the environment and cause destruction of existing plants and animals.Plants,animals and humans are all effective in______.A: our share of resourcesB: a biological creatureC: a given areaD: the maintenance of the ecosystemE: the source of foodF: various species
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第一篇Human EvolutionBeing a man has always been dangerous.There are about 105 males born for every 100 females, but this ratio drops to near balance at the age of maturity,and among 70-year-old there are twice as many women as men. But the great universal of male mortality is being changed.Now,boy babies survive almost as well as girls do. This means that,for the first time,there will be an excess of boys in those crucial years when they are searching for a mate. More important,another chance for natural selection has been removed. Fifty years ago,the chance of a baby(particularly a boy baby)surviving depended on its weight. A kilogram too light or too heavy meant almost certain death.Today it makes almost no difference.Since much of the variation is due to genes,one more agent of evolution has gone.There is another way to commit evolutionary suicide:stay alive,but have fewer children.Few people are as fertile as in the past. Except in some religious communities,very few women have 15 children.Nowadays the number of births,like the age of death,has become average.Most of us have roughly the same number of offspring. Again,differences between people and the opportunity for natural selection to take advantage of it have diminished.India shows what is happening. The country offers wealth for a few in the great cities and poverty for the remaining tribal peoples.The grand mediocrity of today一everyone being the same in survival and number of offspring means that natural selection has lost 80%of its power in upper-middle一class India compared to the tribes.For us,this means that evolution is over;the biological Utopia has arrived.Strangely,it has involved little physical change.No other species fills so many places in nature.But in the past 100,000 years一even the past 100 years一our lives have been transformed but our bodies have not. We did not evolve,because machines and society did it for us.Darwin had a phrase to describe those ignorant of evolution:"they look at an organic being as savage looks at a ship,as at something wholly beyond his comprehension."No doubt we will remember a 20th century way of life beyond comprehension for its ugliness. But however amazed our descendants may be at how far from Utopia we were,they will look just like us.The author argues that our bodies have stopped evolving because______.A:life has been improved by technological advanceB:the number of female babies has been decliningC:our species has reached the highest stage of evolutionD:the difference between wealth and poverty is disappearing
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Ecosystem1. The word “ecosystem” is short for ecological（生态的）system. An ecosystem is where living creatures expand within a given area. You can say that an ecosystem is the natural environment where biological organisms（生物）such as plants,animals and humans co-exist in this world. So naturally that includes you and me. Yes,we are all members of an ecosystem!2 .There are different kinds of ecosystems depending on the type of surface or environ-ment. Most are naturally made such as the ocean or lake and the desert or rainforest.Some are man-made or artificial to encourage co-habitation（同居）between living and non-living things in a monitored environment,such as a zoo or garden.3 .Plants make up the biggest group of biological creatures within an ecosystem,and that's because they are the natural food producers for everyone. Plants raised in the earth need air and collect sunlight to help them grow. When they grow,the plants and its fruits or flowers eventually become a source of food to animals,microorganisms（微生物）and even hu- mans,of course. Food is then converted to energy for the rest of us to function,and this hap-pens in a never-ending cycle until the living creatures die and break up back in the earth.4 .Ecosystems are the basis of survival for all living things.We depend on plants and ani-mals for food. In order for us to exist,we need to grow and care about other organisms. We also need to care for the non-living things within our environment like our air and water so we can continue living as a population. Since plants,animals and humans are all of various species（物种）,we all play a role in maintaining the ecosystem.5 .To preserve our ecosystems,we should stop using too much energy,which happens when we consume more than our share of resources. Humans should not disturb the natural habitat（栖息地）of plants and animals,and allow them to grow healthily for the cycle to con-tinue. Too many people in a habitat can mean displacement（搬迁）: imagine being thrown out of your home because there is no more space for everyone. Worse,overpopulation can also ru- in the environment and cause destruction of existing plants and animals.To protect our ecosystems we should not use more than______.A: our share of resourcesB: a biological creatureC: a given areaD: the maintenance of the ecosystemE: the source of foodF: various species
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Text 3 Up until a few decades ago,our visions of the future were largely-though by no means uniformly-glowingly positive.Science and technology would cure all the ills of humanity,leading to lives of fulfillment and opportunity for all.Now utopia has grown unfashionable,as we have gained a deeper appreciation of the range of threats facing us,from asteroid strike to epidemic flu and to climate change.You might even be tempted to assume that humanity has little future to look forward to.But such gloominess is misplaced.The fossil record shows that many species have endured for millions of years-so why shouldn't we?Take a broader look at our species'place in the universe,and it becomes clear that we have an excellent chance of surviving for tens,if not hundreds,of thousands of years.Look up Homo sapiens in the"Red List"of threatened species of the International Union for the Conversation of Nature（IUCN）,and you will read:"Listed as Least Concern as the species is very widely distributed,adaptable,currently increasing,and there are no major threats resulting in an overall population decline."So what does our deep future hold?A growing number of researchers and organisations are now thinking seriously about that question.For example,the Long Now Foundation has its flagship project a medical clock that is designed to still be marking time thousands of years hence.Perhaps willfully,it may be easier to think about such lengthy timescales than about the more immediate future.The potential evolution of today's technology,and its social consequences,is dazzlingly complicated,and it's perhaps best left to science fiction writers and futurologists to explore the many possibilities we can envisage.That's one reason why we have launched Arc,a new publication dedicated to the near future.But take a longer view and there is a surprising amount that we can say with considerable assurance.As so often,the past holds the key to the future:we have now identified enough of the long-term patterns shaping the history of the planet,and our species,to make evidence-based forecasts about the situations in which our descendants will find themselves.This long perspective makes the pessimistic view of our prospects seem more likely to be a passing fad.To be sure,the future is not all rosy.But we are now knowledgeable enough to reduce many of the risks that threatened the existence of earlier humans,and to improve the lot of those to come.33.Which of the following is true according to Paragraph 5?A.Arc helps limit the scope of futurological studies.
B.Technology offers solutions to social problem.
C.The interest in science fiction is on the rise.
D.Our Immediate future is hard to conceive.
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Text 3 Up until a few decades ago,our visions of the future were largely-though by no means uniformly-glowingly positive.Science and technology would cure all the ills of humanity,leading to lives of fulfillment and opportunity for all.Now utopia has grown unfashionable,as we have gained a deeper appreciation of the range of threats facing us,from asteroid strike to epidemic flu and to climate change.You might even be tempted to assume that humanity has little future to look forward to.But such gloominess is misplaced.The fossil record shows that many species have endured for millions of years-so why shouldn't we?Take a broader look at our species'place in the universe,and it becomes clear that we have an excellent chance of surviving for tens,if not hundreds,of thousands of years.Look up Homo sapiens in the"Red List"of threatened species of the International Union for the Conversation of Nature（IUCN）,and you will read:"Listed as Least Concern as the species is very widely distributed,adaptable,currently increasing,and there are no major threats resulting in an overall population decline."So what does our deep future hold?A growing number of researchers and organisations are now thinking seriously about that question.For example,the Long Now Foundation has its flagship project a medical clock that is designed to still be marking time thousands of years hence.Perhaps willfully,it may be easier to think about such lengthy timescales than about the more immediate future.The potential evolution of today's technology,and its social consequences,is dazzlingly complicated,and it's perhaps best left to science fiction writers and futurologists to explore the many possibilities we can envisage.That's one reason why we have launched Arc,a new publication dedicated to the near future.But take a longer view and there is a surprising amount that we can say with considerable assurance.As so often,the past holds the key to the future:we have now identified enough of the long-term patterns shaping the history of the planet,and our species,to make evidence-based forecasts about the situations in which our descendants will find themselves.This long perspective makes the pessimistic view of our prospects seem more likely to be a passing fad.To be sure,the future is not all rosy.But we are now knowledgeable enough to reduce many of the risks that threatened the existence of earlier humans,and to improve the lot of those to come.31.Our vision of the future used to be inspired byA.our desire for lives of fulfillment
B.our faith in science and technology
C.our awareness of potential risks
D.our belief in equal opportunity
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We are using up our natural resources too quickly and at the same time we are__our environment with dangerous chemicals.A.protecting
B.saving
C.polluting
D.fighting
考题
This kind of animals are on the verge of extinction，because so many are being killed for their fur.A:drying up
B:dying out
C:being exported
D:being transplanted
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This kind of animals are on the verge of extinction,because so many are being killed for their fur.A:drying up
B:dying out
C:being exported
D:being transplanted
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Preserving Nature for FutureDemands for stronger protection for wildlife in Britain sometimes hide the fact that similar needs are felt in the rest of Europe.Studies by the Council of Europe,of which 21 countries are members,have shown that 45 percent of reptile（爬行类的）species and 24 percent of butterflies are in danger of dying out.European concern for wildlife was outlined by Dr.Peter Baum,an expert in the environment and natural resources division of the council,when he spoke at a conference arranged by the administrators of a British national park.The park is one of the few areas in Europe to hold the council’s diploma for nature reserves of the highest quality,and Dr.Peter Baum had come to present it to the park once again.He was afraid that public opinion was turning against national parks,and that those set up in the 1960s and 1970s could not be set up today.But Dr.Baum clearly remained a strong supporter of the view that natural environment needed to be allowed to survive in peace in their own right."No area could be expected to survive both as a true nature reserve and as a tourist attraction,"he went on.The short-sighted（眼光短浅的）view that reserves had to serve immediate human demands for outdoor recreation should be replaced by full acceptance of their importance as places to preserve nature for the future."We forget that they are the guarantee of life systems,on which any built-up area ultimately depends," Dr.Baum went on," we could manage without most industrial products,but we could not manage without nature.However,our natural environment areas,which are the original parts of our countryside,have shrunk to become mere（纯粹的）islands in a spoiled and highly polluted land mass."Recent studies by the council of Europe have indicated that______.A:wildlife needs more protection only in BritainB:all species of wildlife in Europe are in danger of dying outC:there are fewer species of reptiles and butterflies in Europe than elsewhereD:many species of reptiles and butterflies in Europe need protecting
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Many countries are increasing their use of natural gas, wind and other forms of （）AenergyBsourceCpowerDmaterial
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问答题Despite the basic biological, chemical, and physical similarities found in all living things, a diversity of life exists not only among and between species but also within every natural population. The phenomenon of diversity has had a long history of study because so many of the variations that exist in nature are visible to the eye. 1) It has been suggested that sexual reproduction became the dominant type of reproduction among organisms because of its inherent advantage of variability, which is the mechanism that enables a species to adjust to changing conditions.New variations are potentially present in genetic differences, but how preponderant a variation becomes in a gene pool depends upon the number of offspring the mutants or variants produce (differential reproduction). 2)It is possible for a genetic novelty (new variation) to spread in time to all members of a population, especially if the novelty enhances the population’s chances for survival in the environment in which it exists.Thus, when a species is introduced into a new habitat, it either adapts to the change by natural selection or by some other evolutionary mechanism or else it eventually dies off. Because each new habitat means new adaptations, habitat changes have been responsible for the millions of different kinds of species and for the heterogeneity within each species. The total number of animal and plant species is estimated at between 2,000,000 and 4,500,000; authoritative estimates of the number of extinct species range from 15,000,000 up to 16,000,000,000. 3)Although the use of classification as a means of producing some kind of order out of this staggering number of different types of organisms appears as early as the book of Genesis—with references to cattle, beasts, fowl, creeping things, trees, etc.—the first scientific attempt at classification is attributed to the Greek philosopher Aristotle, who tried to establish a system that would indicate the relationship of all things to each other.He arranged everything along a scale, or “ladder of nature”, with nonliving things at the bottom; plants were placed below animals, and man was at the top. 4)Other schemes that have been used for grouping species include large anatomical similarities, such as wings or fins, which indicate a natural relationship, and also similarities in reproductive structures. 5)At the present time taxonomy is based on two major assumptions: one is that similar body construction can be used as a criterion for a classification grouping; the other is that, in addition to structural similarities, evolutionary and molecular relationships between organisms can be used as a means for determining classification.
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单选题A natural fiber rope can be ruined by dampness because it may （）.A
rotB
shrinkC
stretchD
unlay
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单选题To save the wild species from extinction, the author put the stress on __________.A
knowledgeB
techniqueC
persistenceD
confidence
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单选题A great number of national parks have been set up to________ endangered species from extinction.A
conserveB
preserveC
reserveD
observe
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单选题Which of the following statements is not mentioned as serious consequences of coral loss?A
A reduction in tourism.B
Increased coastal damage from hurricanes.C
The extinction of the estimated 1 million species of fish.D
The collapse of reef fisheries.
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单选题The author believes that we feel unhappy maybe because _____.A
it is our natural emotion in the lifeB
culture asks us to be different from othersC
everyone has their own opinions on thingsD
we dislike something in the beginning
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单选题The questions listed in the second paragraph (lines 23-43) directly address all of the following possibilities EXCEPT ______.A
the destruction of animals' natural homesB
the leakage of poisons into the soilC
the creation of landslides from soil displacementD
the emission of harmful car fumesE
the reduction of natural water purification
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