一．Biological diversity has become widely recognized asa critical conservation issue only in the p ast twodecades.The rapid destruction of the tropical rainforests,which are the ecosystems with th e highestknown species diversity on Earth,has awakenedpeople to the importance and fragility of biologicaldiversity.The high rate of species extinctions inthese environments is jolting,but it is im portant torecognize the significance of biological diversity in all ecosystems.As the human popula tioncontinues to expand,it will negatively affect one after another of Earth's ecosystems.Interrestr ial ecosystems and in fringe marine ecosystems(such as wetlands),the most commonproblem is h abitat destruction.In most situations,the result is irreversible.Now humans arebeginning to destro y marine ecosystems through other types of activities,such as disposaland run off of poisonous wa ste;in less than two centuries,by significantly reducing thevariety of species on Earth,they have u nraveled cons of evolution and irrevocably redirectedits course.
Certainly,there have been periods in Earth's history when mass extinctions have occurred.The exti nction of the dinosaurs was caused by some physical event,either climatic or cosmic.There have a lso been less dramatic extinctions,as when natural competition between speciesreached an extrem e conclusion.Only.01percent of the species that have lived on Earth havesurvived to the present, and it was largely chance that determined which species survived andwhich died out. However,nothing has e
ver equaled the magnitude and speed with which the humanspecies is alteri ng the physical and chemical world and demolishing the environment.In fact,there is wide agreem ent that it is the rate of change humans are inflicting,even more than thechanges themselves,that will lead to biological devastation.Life on Earth has continually been influx as slow physical and chemical changes have occurred on Earth,but life needs time to adapt—time for migration and ge netic adaptation within existing species and time for theproliferation of new genetic material and n ew species that may be able to survive in newenvironments.
1.What does the passage mainly discuss?
boston university(A)The causes of the extinction of the dinosaur
(B)The variety of species found in tropical rain forests.
(C)The impact of human activities on Earth's ecosystems
(D)The time required for species to adapt to new environments
2.The word"critical"in line1is closest in meaning to
(A)negative
(B)essential
(C)interesting
(D)complicated
3.The word"jolting"in line5is closest in meaning to
(A)predicted
(B)shocking
(C)unknown
(D)illuminating
4.The author mentions the reduction of the variety of species on Earth in line12to suggest that
(A)new habitats can be created for species
(B)humans are often made ill by polluted water
(C)some species have been made extinct by human activity
(D)an understanding of evolution can prevent certain species from disappearing
5.The author mentions all of the following as examples of the effect of humans oil the world's ecosystems EXCEPT
(A)destruction of the tropical rain forests
(B)habitat destruction in wetlands
(C)damage to marine ecosystems
(D)the introduction of new varieties of plant species
世界十大顶级音响6.The author mentions the extinction of the dinosaurs in the second paragraph to emphasize that
(A)the cause of the dinosaurs extinction is unknown
(B)Earth's climate has changed significantly since the dinosaurs'extinction,
企业变革(C)not all mass extinctions have been caused by human activity
(D)actions by humans could not stop the irreversible process of a species'extinction
7.The word"magnitude"in line20is closest in meaning to
(A)concern
(B)determination
(C)carelessness
(D)extent
8.According to the passage,natural evolutionary change is different from change caused by humans in that changes caused by humans
(A)are occurring at a much faster rate
(B)are less devastating to most species
(C)affect fewer ecosystems
(D)are reversible
9.With which of the following statements would the author be most likely to agree?
(A)Human influence on ecosystems should not be a factor in determining public policy.
(B)The extinction of a few species is an acceptable consequence of human progress.
(C)Technology will provide solutions to problems caused by the destruction ofecosystems.
(D)Humans should be more conscious of the influence they have on ecosystems
正确答案:CBBCD CDAD
二、The Supreme Court'sdecisions on physician-assisted suicide carry important implications for howmedicine seeks to relieve dying patients of pain and suffering。
Although it ruled that there is no constitutional right tophysician-assisted suicide,the Court in effect supported the medical principleof"double effect",a centuries-old moral principle holding that anaction having two effects―a good one that is intended and a harmful one that is foreseen―is permissibleif the actor intends only the good effect。
Doctors have used that principle in recent years to justify usinghigh doses of morphine to control terminally ill patients'pain,even thoughincreasing dosages will eventually kill the patient。
Nancy Dubler,director of Montefiore Medical Center,contends thatthe principle will shield doctors who"until now have very,very stronglyinsisted that they could not give patients sufficient mediation to controltheir pain if that might hasten death."
George Annas,chair of the health law department at BostonUniversity,maintains that,as
long as a doctor prescribes a drug for alegitimate medical purpose,the doctor has done nothing illegal even if thepatient uses the drug to hasten death."It's like surgery,"he says."We don't call those deaths homicides because the doctors didn't intend tokill their patients,although they risked their death.If you're a physician,you can risk your patient's suicide as long as you don't intend theirsuicide."
On another level,many in the medical community acknowledge thatthe assisted-suicide debate has been fueled in part by the despair of patientsfor whom modem medicine has prolonged the physical agony of dying。
Just three weeks before the Court's ruling on physician-assistedsuicide,the National Academy of Science(NAS)released a two-volume report,Approaching Death:Improving Care at the End of Life.It identifies theundertreatment of pain and the aggressive use of"ineffectual and forced medicalprocedures that may prolong and even dishonor the period of dying"as thetwin problems of end-of-life care。
The profession is taking steps to require young doctors to train inhospices,to test knowledge of aggressive pain management therapies,to developa Medicare billing code for hospital-based care,and to develop new standardsfor assessing and treating pain at the end of life。
Annas says lawyers can play a key role in insisting that thesewell-meaning medical initiatives translate into better care.“Largenumbers of physicians seem unconcerned with the pain their patients areneedlessly and predictably suffering,”to the extent thatit constitutes“systematic patient abuse。”He says medicallicensing boards“must make hat painful deaths are presumptively onesthat are incompetently managed and should result in license suspension。”
第一战1.From the first three paragraphs,we learn that
[A]doctors used to increase drug dosages to control their patients'pain。
[B]it is still illegal for doctors to help the dying end theirlives。
[C]the Supreme Court strongly opposes physician-assisted suicide。
成人文章[D]patients have no constitutional right to commit suicide。
2.Which of the following statements its true according to the text?
[A]Doctors will be held guilty if they risk their patients'death。
[B]Modern medicine has assisted terminally ill patients in painlessrecovery。
[C]The Court ruled that high-dosage pain-relieving medication canbe prescribed。
[D]A doctor's medication is no longer justified by his intentions。
3.According to the NAS's report,one of the problems inend-of-life care is
[A]prolonged medical procedures。
[B]inadequate treatment of pain。
[C]systematic drug abuse。
[D]insufficient hospital care。
4.Which of the following best defines the word“aggressive"(line3,paragraph7)?
[A]Bold.
[B]Harmful.
[C]Careless.
[D]Desperate。
5.George Annas would probably agree that doctors should bepunished if they
[A]manage their patients incompetently。
[B]give patients more medicine than needed。
[C]reduce drug dosages for their patients。
[D]prolong the needless suffering of the patients。
三、Learning disabilities are very common.They affect perhaps10percent of all children.Four times as many boys as girls have learning disabilities.
Since about1970，new research has helped brain scientists understand these problems better. Scientists now know there are many different kinds of learning disabilities and that they are caused by many different things.There is no longer any question that all learning disabilities result from differences in the way the brain is organized.
You cannot look at a child and tell if he or she has a learning disability.There is no outward sign of the disorder.So some researchers began looking at the brain itself to learn what might be wrong.
In one study，researchers examined the brain of a learning-disabled person，who had died in an accident.They found two unusual things.One involved cells in the left side of the brain，which control language.These cells normally are white.In the learning-disabled person，however，these cells were gray.The researchers also found that many of the nerve cells were not in a line the way they should have been.The nerve cells were mixed together.
西游记解析The study was carried out under the guidance of Norman Geschwind，an early expert on learning disabilities.Doctor Geschwind proposed that learning disabilities resulted mainly from problems in the left side of the brain.He believed this side of the brain failed to develop normally. Probably，he said，nerve cells there did not connect as they should.So the brain was like an electrical device in which the wires were crossed.
Other researchers did not examine brain tissue.Instead，they measured the brain’s electrical activity and made a map of the electrical signals.
Frank Duffy experimented with this technique at Children’s Hospital Medical Center in Boston.Doctor Duffy found large differences in the brain activity of normal children and those with reading problems.The differences appeared throughout the brain.Doctor Duffy said his research is evidence that reading disabilities involve damage to a wide area of the brain，not just the left side.
1.Scientists found that the brain cells of a learning-disabled person differ from those of a normal person in.
A.structure and function
C.size and arrangement
2.Which of the following is NOT mentioned in the passage？
A.Learning disabilities may result from the unknown area of the brain.
B.Learning disabilities may result from damage to a wide area of the brain.
C.Learning disabilities may result from abnormal organization of brain cells.
D.Learning disabilities may result from problems in the left side of the brain.
3.All of the following statements are true EXCEPT that.
A.many factors account for learning disorder
B.a learning-disabled person shows no outward signs
D.the brain activity of learning-disabled children is different from that of normal children
4.Doctor Duffy believed that.
A.he found the exact cause of learning disabilities
B.the problem of learning disabilities was not limited to the left side of the brain
C.the problem of learning disabilities resulted from the left side of the brain
D.the problem of learning disabilities did not lie in the left side of the brain
5.According to the passage we can conclude that further researches should be made.
< investigate possible influences on brain development and organization
< study how children learn to read and write，and use numbers
< help learning-disabled children to develop their intelligence
< explore how the left side of the brain functions in language learning
答案解析：
大约从1970年以来，新的研究已经帮助脑科学家更好地探讨了这一问题。科学家现在了解到：有很多不同种类的无学习能力，它们由许多不同的原因引起。可以肯定的是：所有的无学习能力都是由大脑组合在一起的不同方式导致的。
你不可能看一眼某个儿童就说他或她有无无学习能力症，这种疾病没有外在表现。因此，一些研究人员开始研究大脑本身，以便了解哪个部位出了什么问题。
在一项研究中，研究人员检查了一个死于意外事故的无学习能力者的大脑。他们发现了两件不寻常的事情。一件是与大脑左半部的细胞有关的，这些细胞控制语言，这些细胞在正常情况下是白的。然而，这个无学习能力者的细胞却是灰的。研究人员还发现，许多神经细胞并没有按照它们应该的方式排成一条直线，而是交织在一起。
这项研究是在诺尔曼·盖茨维德的指导下进行的，他是一个早期研究无学习能力的专家。盖茨维德医生指出，无学习能力主要是由于大脑左半部出现问题造成的。他认为，大脑的这半部分没有正常发育。他说，神经细胞没有按照它们应该的方式连接起来。所以，大脑就像一个线路交叉在一起的电子设备。
其他研究人员没有对脑部组织进行研究。相反，他们检测了脑部的电子活动，并绘制了一幅电子信号图。
弗兰克·达菲在波士顿的儿童医院医学中心用这种技术进行了试验。他发现，正常儿童与那些无学习能力的儿童的脑部活动有很大差异。这些差异遍布大脑。达菲医生说，他的研究证实：无学习能力与大脑许多部位的损伤有关，而不只是与大脑的左半部有关。
1.【正确答案】D
【考点类型】细节判断
【解析过程】科学家们发现，没有学习能力的人的大脑细胞和一个正常人的大脑细胞的不同在于。
A.结构和功能
B.颜和功能
C.大小排序
D.颜和排序
线索1：文章的第3段提到“These cells normally are white.In the learning-disabled person，however，these cells were gray.”
线索2：文章的第3段提到“The researchers also found that many of the nerve cells were not in a line the way they should have been.The nerve cells were mixed together.”
通过线索1和线索2的理解，我们可以判断正确答案应该是选项D.
2.【正确答案】A
【考点类型】细节判断
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