The discovery that the drugs extend the life span of roundworms could have important implications fox human aging as well. There are strong similarities on the molecular level between the proteins and genes thatA. But Komfeld said scientists will not know

题目

The discovery that the drugs extend the life span of roundworms could have important implications fox human aging as well. There are strong similarities on the molecular level between the proteins and genes that

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. ”


相似考题
更多“The discovery that the drugs extend the life span of roundworms could have importan ”相关问题
  • 第1题:

    With a little more patience, you () the job better.

    A、could do

    B、would do

    C、could have done

    D、must have done


    参考答案:C

  • 第2题:

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


    正确答案:F
    空前文字概括介绍了Evason的实验,只有选项F非常清楚地描述了实验对象,并说明为什么使用这个实验对象的原因。这实际上都是介绍实验的一部分。

  • 第3题:

    There may also be other targets not yet explored that affect aging and neuromuscular 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. ”


    正确答案:D
    空前文字提到了另一个问题:神经肌肉活动与延缓衰老的问题;只有选项D继续提到了这个问题,所以选D。

    选项C:该选项指出:“蛔虫实际上并不是理想的实验对象,因为蛔虫不是人类,尽管两者分子结构相同。”显然,这个选项与原文主旨完全背离。连实验对象都是错误的话,文章的结论就更加不可能是正确的。这个选项应该排除。

    选项G:该选项指出:“这种药物已经用于延缓人类衰老了,虽然还需要更多的证据来证明这种药物真的会起作用”。这种论点显然是不对的;没有做过实验怎么能够就冒然使用呢?而且与文中提到的“目前还没有在人类身上做实验”这一点完全相左。这个选项也是明显的干扰选项。

  • 第4题:

    共用题干
    Some Sleep Drugs Do More Than Make You Sleep
    The United States Food and Drug Administration(FDA)has ordered companies to place strong new warnings on thirteen drugs that treat sleep disorders.It also ordered the makers of the sleeping pills to provide information for patients explaining how to safely use the drugs.
    Last Wednesday,the FDA announced that some of these drugs can have unexpected and dangerouseffects.These include the risk of life-threatening allergic(过敏性的)reactions.They also include rareincidents of strange behavior.These include people cooking food,eating and even driving while asleep.The patients later had no memory of doing these activities while asleep.
    Last year,a member of the United States Congress said he had a sleep-driving incident.PatrickKennedy , a representative from Rhode Island,crashed his car into a security barrier near the building wherelawmakers meet.The accident happened in the middle of the night and no one was hurt.Mr.Kennedy saidhe had earlier taken a sleep medicine.He said he was also being treated with a stomach sickness drug thatcan cause sleepiness.
    The FDA did not say in its announcement how many cases of sleep-driving it has documented.However,the New York Times reported last year about people who said they had strange sleep events after taking the drug Ambien.Some reported sleep-driving and sleep-walking.Others said they found evidence after waking in the morning that they had cooked food or eaten in their sleep.But they had no memory of carrying out the activities.
    An FDA official says that these serious side effects of sleep disorder drugs appear to be rare.But,he also said there are probably more cases than are reported.He said the agency believes the risk of such behaviors could be reduced if people take the drugs as directed and do not drink alcohol while taking the drugs.The FDA has advised drug companies to carry out studies to investigate the problem.

    The FDA announced that______.
    A:thirteen drug companies were closed last Wednesday
    B:only thirteen drugs could treat sleeping disorders
    C:some sleep drugs could lead to serious side effects
    D:some makers of sleeping pills provided false information to their patients

    答案:C
    解析:
    由文章第二段第一句可知,上周三,美国食品药物监督管理局发表声明称,一些治疗失眠的药物存在未知的危险副作用,故选C。
    由文章第二段第二句可知,这些药物的副作用包括引起危及生命的过敏性反应,故选C。
    由文章第三段第二句可知,去年美国国会议员Kennedy驾车撞上了一栋大楼旁边的防护栏,故选A。
    由文章第四段第二句可知,《纽约时报》报道称去年有人声称服用药物Ambien后出现了奇怪的睡眠症状,一些人还称出现了睡梦中驾驶和梦中行走的现象,故选D。
    由文章第五段第三句可知,美国食品药物监督管理局认为如果人们按照指导服用,并且服用时避免饮酒,那么出现这些奇怪行为的风险就会降低,故选D。

  • 第5题:

    Bats are surprisingly long-Jived creatures, some__________a life span of around 20 years.

    A.having
    B.had
    C.have
    D.to have

    答案:A
    解析:
    分析句子结构可知,该句为独立主格结构。some为逻辑主语并与谓语动词构成主动关系,故A项正确。

  • 第6题:

    At the first sight the planet Mars does not appear very welcome to any kind of life.It has very little oxygen and water,the temperature at night is below-50~Cand winds of 100 miles per hour cause severe dust storms.However,the surface of the planet seems to show that water flowed across it some time in the past,and it is believed that there is enough ice at the poles to cover the planet with water if it melts.Although there is no life on the Mars now,some scientists think that there may have been some form of life long time ago.At that time,the planet had active volcanoes;the atmosphere was thicker and warmer;and there was water.In fact,in some ways the Mars may have been similar to the Earth,where life exists.
    Some people believe that the Mars could support life in the future if the right conditions were produced.The first step would be to warm the planet using certain gases which trap the Sun's heat in the planet's atmosphere.With warmth,water and carbon dioxide(二氧化碳),simple plants could begin to grow.These plants could slowly make the Mars more suitable for living.It is estimated that the whole process might take between 100,000 and 200,000 years.In the meantime,people could begin to live on the planet in special closed environments.They would provide a lot of useful information about conditions on the Mars and the problems connected with living there.

    There could be life on the Mars in the future if

    A.it supported life in the past
    B.certain gases are used to cool the planet
    C.the atmosphere can be heated enough to grow simple plants
    D.the planet's volcanoes become as active as they were in the past

    答案:C
    解析:
    第二段大意是:如果要想改变火星的条件使之适合居住,首先要提高星球的温度,其方法是用某些气体收集太阳的热能。有了温度、水和二氧化碳,一些植物便可生长。慢慢地使星球适合生存。选项C,“人们可以以提高环境的温度的方式来使一些植物生长”是正确的。

  • 第7题:

    At the first sight the planet Mars does not appear very welcome to any kind of life.It has very little oxygen and water,the temperature at night is below-50~Cand winds of 100 miles per hour cause severe dust storms.However,the surface of the planet seems to show that water flowed across it some time in the past,and it is believed that there is enough ice at the poles to cover the planet with water if it melts.Although there is no life on the Mars now,some scientists think that there may have been some form of life long time ago.At that time,the planet had active volcanoes;the atmosphere was thicker and warmer;and there was water.In fact,in some ways the Mars may have been similar to the Earth,where life exists.
    Some people believe that the Mars could support life in the future if the right conditions were produced.The first step would be to warm the planet using certain gases which trap the Sun's heat in the planet's atmosphere.With warmth,water and carbon dioxide(二氧化碳),simple plants could begin to grow.These plants could slowly make the Mars more suitable for living.It is estimated that the whole process might take between 100,000 and 200,000 years.In the meantime,people could begin to live on the planet in special closed environments.They would provide a lot of useful information about conditions on the Mars and the problems connected with living there.

    Some scientists think there may have been life on the Mars in the past because__.

    A.there is no life there now
    B.there is a large amount of water at the poles
    C.the Mars may be able to support life in the future
    D.conditions may have been similar to those on the Earth

    答案:D
    解析:
    第一段大意是:人们最初对火星的印象是火星上不可能有生命。因为几乎没有氧气和水,并且夜间温度低于-50°C,同时还有每小时l00英里的风速引起的严重的沙尘暴。然而星球的表面却告诉我们,过去的某个时段水曾经从这里流过。人们相信极地有足够的冰,一旦融化便可覆盖整个星球。虽然现在火星上没有生命,但在过去很久很久以前,生命很有可能存在过。由此可看出,生命所需的条件——水和氧——在火星上和在地球上是相似的。所以选项D正确。而选项B说火星上有水是不对的。火星的极地有冰,只有当冰融化后才能使整个星球有水。

  • 第8题:

    单选题
    Well-meaning friends and family members often tell those who live alone that _____.
    A

    they should end their singleton as soon as possible

    B

    they should live together with other singletons

    C

    singleton is an acceptable life-style

    D

    singleton can shorten one’s life-span


    正确答案: D
    解析:
    文章一开始作者提到好心的朋友和家人都在安慰独居的人,并跟他们说没有人做伴,天也不会塌下来的。singleton意为“独居者”,原是超纲词汇,但文中已有解释,考生可明白其意思。

  • 第9题:

    名词解释题
    Hayflick life span (Hayflick界限)

    正确答案: 1961年,Leonard Hayflick利用来自胚胎和成体的成纤维细胞进行体外培养,发现:胚胎的成纤维细胞分裂传代50次后开始衰退和死亡,相反,来自成年组织的成纤维细胞只能培养15~30代就开始死亡。Hayflick等还发现,动物体细胞在体外可传代的次数,与物种的寿命有关;细胞的分裂能力与个体的年龄有关,由于上述规律是Hayflick研究和发现的,故称为Hayflick界限。
    解析: 暂无解析

  • 第10题:

    单选题
    His opponent having sprained his wrist, Andrew could have won by exploiting this weakness, but he chose not to do it.
    A

    His opponent having sprained his wrist, Andrew could have won by exploiting this weakness, but he chose not to do it.

    B

    Andrew could have won by exploiting this weakness after his opponent sprained his wrist, but he chose not to do so.

    C

    Choosing not to do so, Andrew could have won after his opponent sprained his wrist by exploiting this weakness.

    D

    After his opponent sprained his wrist, Andrew could have won by exploiting this weakness, but he chose not to do so.

    E

    After his opponent sprained his wrist, Andrew could have, but chose not to do it, won by exploiting this weakness.


    正确答案: D
    解析:
    A、E项句子结尾处的it指代不明;B、C项的学术不合逻辑,故应选D项。

  • 第11题:

    单选题
    Careful surveys have indicated that as many as 50 percent of patients do not take drugs ____ directed.
    A

    like

    B

    so

    C

    which

    D

    as


    正确答案: D
    解析:

  • 第12题:

    单选题
    As a result of the epidemic of AIDS in Africa, _____.
    A

    the life span for most of the people has been reduced by 40 years

    B

    most young people have been infected with human immunodeficiency virus

    C

    people will have to learn to live with the disease for over 50 years

    D

    the achievements made in preserving people’s health in the past will be wiped off


    正确答案: D
    解析:
    第四段第二句作者提到,到2025年艾滋病将成为非洲年轻人的最大杀手,它可以使一些国家人口的平均寿命降到40岁,仅艾滋病一项就会使过去50年在公共健康方面取得的成就化为乌有。

  • 第13题:

    (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. ”


    正确答案:E
    空前文字提出了文章的主题,也就是概括性地介绍了文章的内容:“一项研究表明治疗人类突发性疾病的药物能延缓虫子的衰老,由于人类的分子结构与虫子相似,所以有可能这种药物也能延缓人类的衰老”。只有选项E继续概括性地介绍了文章的内容:“这项研究同样也表明神经肌肉活动与衰老有关系”。

  • 第14题:

    Ethosuzimide, which was developed in the 1950s, is commonly used to treat epilepsy, though it is no known precisely how the drug controls convulsions. There is no anecdotal evidence that it has had an anti-aglng effect in people. The next step, Komfeld says, is to test if the drugs have an anti-aging effect on animal like flies and mice。 Very little is known about the aging process. From genetic analysis, researchers have found that an in sulin-like signaling system regulates aging and longevity. A good diet can delay aging and extend a person life span. But scientists know virtually nothing about the effect of drugs on aging. “It’s a big void, ” Konfeld said。 In addition to delaying age-related degenerative changes, the drugs also increased neuromuscular activty, suggesting a link between the neuromuscular system and the aging process。

    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. ”


    正确答案:A
    空前文字提到:“有理由相信这种实验结论对更高级的动物,如人类,也同样适用”。所以这一空应该继续谈到实验结果对人类究竟是不是适用的问题。选项A提到:“但是科学家们目前还不知道究竟对人类是不是适用,除非也在人类身上做相同的实验”。显然,选项A最合适。

  • 第15题:

    ______the survivors know more of how to cope with cold water in the sinking of MV Titanic in 1912 countless lives ______.

    A.Have / could have been saved

    B.Have / could have saved

    C.Had / could has saved

    D.had / could have been saved


    正确答案:D
    如果那些幸存者懂得多一些在冷水中的救生方法,那么在1912年泰坦尼克号沉没事件中将会有更多的生命能幸存。

  • 第16题:

    共用题干
    Some Sleep Drugs Do More Than Make You Sleep
    The United States Food and Drug Administration(FDA)has ordered companies to place strong new warnings on thirteen drugs that treat sleep disorders.It also ordered the makers of the sleeping pills to provide information for patients explaining how to safely use the drugs.
    Last Wednesday,the FDA announced that some of these drugs can have unexpected and dangerouseffects.These include the risk of life-threatening allergic(过敏性的)reactions.They also include rareincidents of strange behavior.These include people cooking food,eating and even driving while asleep.The patients later had no memory of doing these activities while asleep.
    Last year,a member of the United States Congress said he had a sleep-driving incident.PatrickKennedy , a representative from Rhode Island,crashed his car into a security barrier near the building wherelawmakers meet.The accident happened in the middle of the night and no one was hurt.Mr.Kennedy saidhe had earlier taken a sleep medicine.He said he was also being treated with a stomach sickness drug thatcan cause sleepiness.
    The FDA did not say in its announcement how many cases of sleep-driving it has documented.However,the New York Times reported last year about people who said they had strange sleep events after taking the drug Ambien.Some reported sleep-driving and sleep-walking.Others said they found evidence after waking in the morning that they had cooked food or eaten in their sleep.But they had no memory of carrying out the activities.
    An FDA official says that these serious side effects of sleep disorder drugs appear to be rare.But,he also said there are probably more cases than are reported.He said the agency believes the risk of such behaviors could be reduced if people take the drugs as directed and do not drink alcohol while taking the drugs.The FDA has advised drug companies to carry out studies to investigate the problem.

    The FDA warned that some sleeping pills______.
    A:can help people to learn to cook
    B:prevent people from driving while asleep
    C:present life-threatening risk to patients
    D:have severe effect on a patient's long-term memory

    答案:C
    解析:
    由文章第二段第一句可知,上周三,美国食品药物监督管理局发表声明称,一些治疗失眠的药物存在未知的危险副作用,故选C。
    由文章第二段第二句可知,这些药物的副作用包括引起危及生命的过敏性反应,故选C。
    由文章第三段第二句可知,去年美国国会议员Kennedy驾车撞上了一栋大楼旁边的防护栏,故选A。
    由文章第四段第二句可知,《纽约时报》报道称去年有人声称服用药物Ambien后出现了奇怪的睡眠症状,一些人还称出现了睡梦中驾驶和梦中行走的现象,故选D。
    由文章第五段第三句可知,美国食品药物监督管理局认为如果人们按照指导服用,并且服用时避免饮酒,那么出现这些奇怪行为的风险就会降低,故选D。

  • 第17题:

    At the first sight the planet Mars does not appear very welcome to any kind of life.It has very little oxygen and water,the temperature at night is below-50~Cand winds of 100 miles per hour cause severe dust storms.However,the surface of the planet seems to show that water flowed across it some time in the past,and it is believed that there is enough ice at the poles to cover the planet with water if it melts.Although there is no life on the Mars now,some scientists think that there may have been some form of life long time ago.At that time,the planet had active volcanoes;the atmosphere was thicker and warmer;and there was water.In fact,in some ways the Mars may have been similar to the Earth,where life exists.
    Some people believe that the Mars could support life in the future if the right conditions were produced.The first step would be to warm the planet using certain gases which trap the Sun's heat in the planet's atmosphere.With warmth,water and carbon dioxide(二氧化碳),simple plants could begin to grow.These plants could slowly make the Mars more suitable for living.It is estimated that the whole process might take between 100,000 and 200,000 years.In the meantime,people could begin to live on the planet in special closed environments.They would provide a lot of useful information about conditions on the Mars and the problems connected with living there.

    Which is the best title for this passage?

    A.The Possibility of Life on the Mars
    B.Future Conditions on the Mars
    C.The Mars and the Earth
    D.A Study of the Climate of the Mars

    答案:A
    解析:
    文章的标题就是文章的中心。作者从火星上曾经有过生命的证明谈到未来通过提高温度而使火星适合生存的设想,表明文章的中心是:火星具有生命存在可能性。

  • 第18题:

    At the first sight the planet Mars does not appear very welcome to any kind of life.It has very little oxygen and water,the temperature at night is below-50~Cand winds of 100 miles per hour cause severe dust storms.However,the surface of the planet seems to show that water flowed across it some time in the past,and it is believed that there is enough ice at the poles to cover the planet with water if it melts.Although there is no life on the Mars now,some scientists think that there may have been some form of life long time ago.At that time,the planet had active volcanoes;the atmosphere was thicker and warmer;and there was water.In fact,in some ways the Mars may have been similar to the Earth,where life exists.
    Some people believe that the Mars could support life in the future if the right conditions were produced.The first step would be to warm the planet using certain gases which trap the Sun's heat in the planet's atmosphere.With warmth,water and carbon dioxide(二氧化碳),simple plants could begin to grow.These plants could slowly make the Mars more suitable for living.It is estimated that the whole process might take between 100,000 and 200,000 years.In the meantime,people could begin to live on the planet in special closed environments.They would provide a lot of useful information about conditions on the Mars and the problems connected with living there.

    The author's attitude towards the possibility of life on the Mars in the future is__.

    A.doubtful
    B.positive
    C.negative
    D.uninterested

    答案:B
    解析:
    根据全文可以判断,作者对人类在火星上生存的可能性抱着积极、乐观的态度。

  • 第19题:

    The operation could prolong his life by two or three years.

    A:broaden
    B:worsen
    C:extend
    D:accelerate

    答案:C
    解析:
    本句意思:这次手术可使他多活两三年。prolong意为“延长”,与extend (延伸,延续)意思相近。broaden扩大;worsen恶化;accelerate加速。

  • 第20题:

    单选题
    The controversy mentioned in the passage focuses on _____.
    A

    whether psychologists should use drugs to cure their patients

    B

    how psychologists should treat their patients

    C

    the fact that all of the drugs have harmful side effects

    D

    the extent to which drugs should be used to fight psychological illness


    正确答案: B
    解析:
    第二段第一句作者提到现代医学界重要的争论之一就是医生,特别是心理医生,应该在多大程度上依靠药物来“治愈”他们的患者。

  • 第21题:

    单选题
    ()the survivors known more of how to cope with cold water in the sinking of MV Titanic in 1912 countless lives().
    A

    Have/could have been saved

    B

    Have/could have saved

    C

    Had/could has saved

    D

    Had/could have been saved


    正确答案: C
    解析: 暂无解析

  • 第22题:

    单选题
    Which of the following is NOT a reason why health care investment fails to bring a longer life?
    A

    Drug reaction due to improper use of drugs.

    B

    Imbalanced distribution of health care money.

    C

    Soaring prices of both drugs and new therapies.

    D

    Failure of many highly-evaluated medical treatments.


    正确答案: B
    解析:
    第四段分析了医药方面投入巨大但却未能使美国人寿命更长的原因。其中谈到:一、有些被认为是神奇的药物或治疗其实并不十分有效;二、投入主要集中在生命垂危或年纪很大的病人,对于提高整体寿命作用不大;三、对于某些药物的不良反应。并没有谈到医药价格的上涨。

  • 第23题:

    问答题
    His hands and fingernails suggested that he hadn't done heavy manual work in this life-he could have been a rich man.

    正确答案:
    解析: