1、考研英语（阅读）-试卷 424 及答案解析(总分：60.00，做题时间：90 分钟)一、Reading Comprehensio(总题数：10，分数：60.00)1.Section II Reading Comprehension_2.Part ADirections: Read the following four texts. Answer the questions below each text by choosing A, B, C or D._The cause of Alzheimers disease is unknown, but various studies sugges
2、t that its risk factors extend beyond genetics. Some studies have associated the disease with a lack of physical activity. Others have linked Alzheimers disease to a lack of stimulating brainworkfitting a use-it-or-lose-it situation of cognitive decline. A new study supports the view that both kinds
3、 of inactivity pose risks. People who have the memory loss, confusion, and disorientation of Alzheimers disease in old age were generally less active physically and intellectually between the ages of 20 and 60 than were people who dont have the disease, according to study coauthor Robert P. Friedlan
4、d, a neurologist at Case Western Reserve University School of Medicine in Cleveland, and his colleagues. After establishing an average overall activity level for all the studys participants, the researchers discovered that the Alzheimers patients were nearly four times as likely as the people withou
5、t Alzheimers to fall below that average. In particular, the non-Alzheimers volunteers had devoted more time on average between ages 40 and 60 to intellectual activities and less to passive ones than had those who developed the disease. The only single activity in which Alzheimers patients on average
6、 significantly outperformed their counterparts was watching television, Friedland says. While certain genetic factors seem to influence the brain deterioration associated with Alzheimers, these dont account for all cases of the disease. Indeed, studies of genetically similar people living in separat
7、e countries show divergent rates of Alzheimers disease. The new study accounted for differences in education and income but not occupation. It doesnt point to a cause of Alzheimers or even predict who might develop the disease, but it does reinforce the value of remaining physically and mentally act
8、ive, Friedland says. From an evolutionary standpoint, people are still physically designed to be active hunters and gatherers. “Being a couch potato,“ he says, “is not our natural state.“ Intellectual stimulation may work the same way, he says. Studies indicate that a higher educational level makes
9、a person less likely to develop Alzheimers disease. Some researchers suggest that challenging the brain builds reserves of functional brain tissue that protect people against the disease. “This is a very intriguing study“ built on “extremely rigorous“ data collection, says Mary S. Mittelman, a scien
10、tist at New York University School of Medicine. However, she wonders why some people are active during their middle years while others arent. Could it be that a sedentary lifestyle really contributes to the development of Alzheimers, or does the illness begin early in life and subtly steer a person
11、toward such a lifestyle? “ It could be a combination of both,“ Friedland says.（分数：10.00）(1).From the first two paragraphs, we learn that_.（分数：2.00）A.Alzheimers disease has nothing to do with genetic transmissionB.intellectual work may reduce the risk of getting Alzheimers diseaseC.an inactive child
12、is more likely to get Alzheimers disease than an active oneD.a lack of physical exercise has been proved to be a cause of Alzheimers disease(2).Alzheimers patients watching television is mentioned to suggest that_.（分数：2.00）A.watching television may do great harm to ones healthB.there is a controvers
13、y over whether Alzheimers patients should watch TVC.one intellectual activity Alzheimers patients did more is watching televisionD.passive activities such as watching television may lead to Alzheimers disease(3).According to the study, Alzheimers disease may have something to do with peoples_.（分数：2.
14、00）A.professionB.living environmentC.salaryD.nationality(4).The word “sedentary“(Line 3, Para. 7) means_.（分数：2.00）A.involving much sittingB.showing physical fatigueC.involving much standingD.showing mental tiredness(5).To which of the following statements would Friedland most likely agree?（分数：2.00）A
15、.Educational difference is a cause of Alzheimers disease.B.People should participate actively in hunting and gathering.C.Peoples lifestyle may lead to Alzheimers disease and vice versa.D.Intellectual work may ward off Alzheimers disease better than physical work.The immune system is equal in complex
16、ity to the combined intricacies of the brain and nervous system. The success of the immune system in defending the body relies on a dynamic regulatory communications network consisting of millions and millions of cells. Organized into sets and subsets, these cells pass information back and forth lik
17、e clouds of bees swarming around a hive. The result is a sensitive system of checks and balances that produces an immune response that is prompt, appropriate, effective and self-limiting. At the heart of the immune system is the ability to distinguish between self and non-self. When immune defenders
18、 encounter cells or organisms carrying foreign or non-self molecules, the immune troops move quickly to eliminate the invaders. Virtually every body cell carries distinctive molecules that identify it as self. The bodys immune defenses do not normally attack tissues that carry a self marker. Rather,
19、 immune cells and other body cells coexist peaceably in a state known as self-tolerance. When a normally functioning immune system attacks a non-self molecule, the system has the ability to remember the specifics of the foreign body. Upon subsequent encounters with the same species of molecules, the
20、 immune system reacts accordingly. With the possible exception of antibodies passed during lactation, this so-called immune system memory is not inherited. Despite the occurrence of a virus in your family, your immune system must learn from experience with the many millions of distinctive non-self m
21、olecules in the sea of microbes in which we live. Learning necessitates producing the appropriate molecules and cells to match up with and counteract each non-self invader. Any substance capable of stimulating an immune response is called an antigen. Tissues or cells from another individual (except
22、an identical twin, whose cells carry identical self-markers) act as antigens; because the immune system recognizes transplanted tissues as foreign, it rejects them. The body will even reject nourishing proteins unless they are first broken down by the digestive system into their primary, non-antigen
23、ic building blocks. An antigen announces its foreignness by means of intricate and characteristic shapes called epitopes, which stick out from its surface. Most antigens, even the simplest microbes, carry several different kinds of epitopes on their surface, some may even carry several hundred. Some
24、 epitopes will be more effective than others at stimulating an immune response. Only in abnormal situations does the immune system wrongly identify self as non-self and execute a misdirected immune attack. The result can be so-called autoimmune disease. The painful side effects of these diseases are
25、 caused by a persons immune system actually attacking itself.（分数：10.00）(1).We know from the text that the immune system_.（分数：2.00）A.is no less complicated than the nervous systemB.far exceeds the human brain in intricacyC.is enclosed by numerous sensitive cellsD.results in an effective communication
26、s network(2).The principal task of the immune system is to_.（分数：2.00）A.recognize and eliminate all foreign molecules that enter the bodyB.remove all the substances that invade the body organismsC.defend the body from the attacks of different viruses and bacteriaD.identify and specify all non-self mo
27、lecules it encounters(3).The remembering power of a persons immune system is_.（分数：2.00）A.mostly descended from his/her ancestorsB.partially passed down from his/her motherC.mainly acquired through fighting against foreign cellsD.basically generated by its communications network(4).A tissue transplan
28、ted from father to daughter would be less acceptable than that transplanted between twins because_.（分数：2.00）A.the ages of the twins tissues are exactly alikeB.the twins tissues have the same self-markersC.the father and daughter are different in sexD.the twins immune systems possess identical memory
29、(5).The main idea of the text may be generalized as_.（分数：2.00）A.the success of the immune system in distinguishing foreign substancesB.the normal and abnormal activities of the immune system in the bodyC.the unfavorable effects of the immune system on organ transplantationD.the essential duties of t
30、he immune system in guarding the bodyCommunity cancer clusters are viewed quite differently by citizen activists than by epidemiologists. Environmentalists and concerned local residents, for instance, might immediately suspect environmental radiation as the culprit when a high incidence of cancer ca
31、ses occurs near a nuclear facility. Epidemiologists, in contrast, would be more likely to say that the incidences were “inconclusive“ or the result of pure chance. And when a breast cancer survivor, Lorraine Pace, mapped 20 breast cancer cases occurring in her West Islip, Long Island, community, her
32、 rudimentary research efforts were guided more by hopethat a specific environmental agent could be correlated with the cancersthan by scientific method. When epidemiologists study clusters of cancer cases and other noncontagious conditions such as birth defects or miscarriage, they take several vari
33、ables into account, such as background rate (the number of people affected in the general population), cluster size, and specificity (any notable characteristics of the individual affected in each case). If a cluster is both large and specific, it is easier for epidemiologists to assign blame. Not o
34、nly must each variable be considered on its own, but it must also be combined with others. Lung cancer is very common in the general population. Yet when a huge number of cases turned up among World War II shipbuilders who had all worked with asbestos, the size of the cluster and the fact that the m
35、en had had similar occupational asbestos exposures enabled epidemiologists to assign blame to the fibrous mineral. Although several known carcinogens have been discovered through these kinds of occupational or medical clusters, only one community cancer cluster has ever been traced to an environment
36、al cause. Health officials often discount a communitys suspicion of a common environmental cause because citizens tend to include cases that were diagnosed before the afflicted individuals moved into the neighborhood. Add to this is the problem of cancers latency. Unlike an infectious disease such a
37、s cholera, which is caused by a recent exposure to food or water contaminated with the cholera bacterium, cancer may have its roots in an exposure that occurred 10 to 20 years earlier. Do all these caveats mean that the hard work of Lorraine Pace and other community activists is for nothing? Not nec
38、essarily. Together with many other reports of breast cancer clusters on Long Island, the West Islip situation highlighted by Pace has helped epidemiologists lay the groundwork for a well-designed scientific study.（分数：10.00）(1).The “hope“ mentioned in Paragraph 1 refers specifically to Paces desire t
39、o_.（分数：2.00）A.help reduce the incidence of breast cancer in future generationsB.improve her chances of surviving breast cancerC.determine the cause responsible for her own breast cancer caseD.identify a particular cause for the breast cancer cases in West Islip(2).The case of the World War II shipbu
40、ilders with lung cancer is an example of_.（分数：2.00）A.an occupational clusterB.a medical clusterC.a radiation clusterD.an environmental cluster(3).The text suggests that the fact “only one community cancer cluster had ever been traced to an environmental cause“ (Para. 3) is most likely due to the_.（分
41、数：2.00）A.methodological difficulties in analyzing community cancer clustersB.reluctance of epidemiologists to investigate environmental factors in cancerC.lack of credibility of citizen activists in claiming to have identified cancer agentsD.effectiveness of regulations restricting the use of carcin
42、ogens in residential areas(4).Activists may mistakenly consider a particular incidence of cancer as part of a community cluster despite the fact that_.（分数：2.00）A.the affected individual never worked with any carcinogenic materialB.the cancer was actually caused by an exposure long time agoC.the size
43、 of the cluster is too small to be meaningfulD.the cancer actually arose in a different geographic location(5).The word “caveats“ (Line 1, Para. 4) refers to_.（分数：2.00）A.refusals by epidemiologists to examine the work of Pace and other activistsB.potential flaws in amateur studies of cancer clusterC
44、.warnings by activists concerning environmental dangers in their communitiesD.tendencies of activists to assume environmental causes for cancerDoctors are having a hard go of things. Squeezed by falling refund, soaring malpractice insurance and punishing patient loads, they shouldnt have much to fea
45、r from the likes of Wal-Mart. But the fact is, the greeter in the red vest is increasingly going toe-to-toe with the doctor in the white coatand winningthanks to the growing phenomenon of retail health clinics. Retail clinicsfree-standing, walk-in medical providers located in drug stores, shopping m
46、alls and stores like Wal-Mart, Target and Walgreensare rapidly becoming to the health-care industry what Fotomat was to the camera world. There are roughly 1,000 clinics now operating in the US, offering acute care for such routine problems as throat infections and earaches as well as providing diab
47、etes and cholesterol (a white substance found in animal tissues and various foods) screenings, routine checkups and vaccinations (the introduction of preventive medicine into the body to produce immunity to a specific disease). The fees are lowand conspicuously posted; nearly all of the clinics trea
48、t both the insured and uninsured, and there is little or no waiting time. With 50 million Americans lacking health insurance and family budgets collapsing under the weight of medical costs, whats not to like about the clinics? Plenty, say physicians associations, whose members warn that clinicswhich are typically staffed by nurse practitioners and are positioned in stores that also sell prescriptionswill be inclined to misdiagnose and overprescribe. Worse, they are not built to provide long-term care for chronic conditions such as hypertension (elevatio
