医学类文章25篇精练全解

第一节 医学类文章25篇精练全解

Passage 1

People who sleep fewer than six hours a night are more likely to die early，researchers have found in a study they claim provides“unequivocal（毫无疑问的，确实的）evidence” of a link between sleep deprivation and premature death.They discovered that people who slept for less than six hours each night were 12 per cent more likely to die prematurely— before the age of 65—than those who slept the recommended six to eight hours a night.

The team from the University of Warwick and Federico II University Medical School in Naples analyzed 16 studies involving a total of 1.3 million people before reaching their conclusions.They pointed out that previous studies had shown that sleep deprivation was associated with heart disease，high blood pressure，obesity，Type 2 diabetes，and high cholesterol.

However，the researchers also found that sleeping too much was linked to an early death.Those who slept for more than nine hours a night were 30 per cent more likely to die early，the research published in the journal Sleep found.That directly contradicts research published in the same journal last week which suggested that people who slept for ten hours or longer a night were more likely to live to 100.This was thought to be because people who lived into extreme old age were healthier and therefore slept better.

However，the authors of the latest research contradicted this and suggested that long sleep was a sign of underlying illnesses such as depression and low levels of physical activity.Some cancer is also associated with sleeping for longer.Professor Francesco Cappuccio，leader of the Sleep，Health and Society Programme at the University of Warwick and Consultant Physician at the University Hospitals Coventry and Warwickshire NHS Trust，said：“Whilst short sleep may represent a cause of ill-health，long sleep is believed to represent more an indicator of ill-health.”

“Consistently sleeping six to eight hours per night may be optimal for health.The duration of sleep should be regarded as an additional behavioral risk factor，or risk marker， influenced by the environment and possibly amenable to change through both education and counseling as well as through measures of public health aimed at favorable modifications of the physical and working environments.”

1.According to the passage，which one has the least possibility to die early？

A.Sleep less than six hours per night.

B.Sleep more than six hours per night.

C.Sleep between six to eight hours per night.

D.Sleep more than nine hours per night.

2.When someone is lack of sleep for a long time，he is apt to have some kinds of diseases EXCEPT____.

A.heart disease B.high blood pressure

C.fatness D.tuberculosis

3.What can we infer from the passage？

A.The longer hours we sleep，the healthier we would be.

B.The shorter hours we sleep，the healthier we would be.

C.People who sleep between six to eight hours wouldn’t die early.

D.If someone tends to sleep long hours，then it indicates that there is something wrong with his body.

4.What does“whilst”（Line 6，Para.4）probably mean？

A.Although. B.Furthermore.

C.Because. D.Since.

5.Which is the best title of the passage？

A.Sleep and Health B.Long Hours’Sleep Leads to Early Death

C.Don’t Sleep too Long D.The Deterioration of our Health Status

Passage 2

Imagine eating everything delicious you want—with none of the fat.That would be great，wouldn’t it？

New“fake fat”products appeared on store shelves in the United States recently，but not everyone is happy about it.Makers of the products，which contain a compound called olestra，say food manufacturers can now eliminate fat from certain foods.Critics，however， say the new compound can rob the body of essential vitamins and nutrients（营养物）and can also cause unpleasant side effects in some people.So it’s up to consumers to decide whether the new fat-free products taste good enough to keep eating.

Chemists discovered olestra in the late 1960s，when they were searching for a fat that could be digested by infants more easily.Instead of finding the desired fat，the researchers created a fat that can’t be digested at all.

Normally，special chemicals in the intestines（肠）“grab”molecules of regular fat and break them down so they can be used by the body.A molecule of regular fat is made up of three molecules of substances called fatty acids.

The fatty acids are absorbed by the intestines and bring with them the essential vitamins A，D，E，and K.When fat molecules are present in the intestines with any of those vitamins，the vitamins attach to the molecules and are carried into the bloodstream.

Olestra，which is made from six to eight molecules of fatty acids，is too large for the intestines to absorb.It just slides through the intestines without being broken down. Manufacturers say it’s that ability to slide unchanged through the intestines that make olestra as valuable as a fat substitute.It provides consumers with the taste of regular fat without any bad effects on the body.But critics say olestra can prevent vitamins A，D，E，and K from being absorbed.It can also prevent the absorption of carotenoids（类胡萝卜素），compounds that may reduce the risk of cancer，heart disease，etc.

Manufacturers are adding vitamins A，D，E，and K as well as carotenoids to their products now.Even so，some nutritionists are still concerned that people might eat unlimited amounts of food made with the fat substitute without worrying about how many calories they are consuming.

1.We learn from the passage that olestra is a substance that____.

A.contains plenty of nutrients

B.renders foods calorie-free while retaining their vitamins

C.makes foods easily digestible

D.makes foods fat-free while keeping them delicious

2.The result of the search for an easily digestible fat turned out to be____.

A.commercially useless B.just as anticipated

C.somewhat controversial D.quite unexpected

3.Which of the following is NOT true about the fatty acid？

A.The fatty acid is made up of three molecules of substances.

B.The fatty acid can be absorbed by the intestines.

C.The fatty acid brings the essential vitamins A，D，E and K to the intestines.

D.Olestra is made from six to eight molecules of fatty acids.

4.Olestra is different from ordinary fats in that____.

A.it passes through the intestines without being absorbed

B.it facilitates the absorption of vitamins by the body

C.it helps reduce the incidence of heart disease

D.it prevents excessive intake of vitamins

5.Why are nutritionists concerned about adding vitamins to olestra？

A.It may lead to the over-consumption of vitamins.

B.People may be induced to eat more than is necessary.

C.The function of the intestines may be weakened.

D.It may trigger a new wave of fake food production.

Passage 3

Pier 17 in downtown Manhattan is not the most likely destination for theatre-goers.But here on the East River，among the wailing seagulls，frying fish and tourists，is an enchanting offer of entertainment.Spiegel world is back in town for its second summer，with two spicy cabaret shows of dance，music，and acrobatics and burlesque.Called“Absinthe”and“La Vie”，the shows are staged in the anachronistic opulence of a Spiegel tent（Flemish for“tent of mirrors”）.

Nobody seems to know how many of these European pavilions are left but most people agree that there are fewer than 20.Built by hand without nails，Spiegel tents are beautiful assemblies of teak，velvet，stained glass and bevelled mirrors，created originally in Belgium in the early 20th century as mobile dance halls.Only two families in Belgium and the Netherlands still know how to make them，producing one every five or ten years or so，says Vallejo Gantner， one of the show’s producers and a long-time Spiegel tent aficionado.“But you know it when you walk into an old one.They have a special boutique quality.”

This one，which dates from the 1920s and has a painted art-nouveau facade，lends continental glamour to the pier.It holds about 350 people on wooden chairs and banquettes around a modest，circular stage.And it is this intimacy，this proximity to the performers，that gives these shows their special feel.Erotic contortionists，balletic hand-balancers and bawdy jugglers emanate a sweaty，tangible humanity.Many of them，Mr.Gantner explains，have left larger circus troupes，such as Cirque du Soleil，in order to make eye-contact with their audience.The simplicity of the staging gives their performances a gritty authenticity.

Once in a while，a family on a children’s outing is fooled by Spiegel world’s festive red-and-blue tent spires.Make no mistake：the shows are for adults.“La Vie”，created by Les 7 Doigts de la Main，a Montreal-based troupe，laces an array of artfully sexy circus acts with the premise that everyone is dead and in purgatory，travelling on“a flight to hell that never quite gets there”.Wearing what looks like a straitjacket，a contortionist moves in a highly unsettling way to a recording of“Crazy”，crooned by Patsy Cline.The show closes with a steamy pas de deux between the devilish master of ceremonies and the evening’s lip-curling seductress.

“Absinthe”is a more explicit grab-bag of stripping，cross-dressing and intrigue，without a unifying theme.The show’s strongest moments come from the acrobats，all of whom carry a powerful sexual charge.Two women sway with suggestive grace on the trapeze.An aerialist in black trousers，his sculpted chest glistening，pulls and twists himself up two hanging straps to the lusty music of“Jealous Guy”，sung by a transvestite diva.

Sexy but not tawdry.Despite colorful language and a brief moment of unnecessary male nudity in“La Vie”，the setting is too elegant and the talent too astonishing for that.It’s a bit of risquéfun that has been warmly received by New Yorkers，many of whom have grown tired of the wholesome， tourist-friendly fare of Broadway.Last summer“Absinthe”ran for two months to sell-out crowds；this year’s two-show programme is for three months until the end of September.

1.According to the passage，Spiegel world is probably____.

A.a series shows of dance，music，acrobatics and burlesque with boutique quality

B.a mobile dance hall of long history as well as exquisite decoration

C.a troupe performing certain programmes for the public

D.a traditional form of entertainment derived from some ancient European countries

2.By mentioning that“Pier 17 in downtown Manhattan is not the most likely destination for theatre-goers”，the author wants to____.

A.imply that theatre-goers are paying much attention to the environment of performance

B.show that Pier 17 is not a place for a formal performance of the theatre

C.prove that the shows in Spiegel tents are very attractive

D.tell us the status of the place where the shows of“Absinthe”and“La Vie”are presented

3.The performances staged in Spiegel tents are different from the other ones mainly in that____.

A.they are on show in the pier rather than in the theatre

B.the seats are arranged around the stage so that the audience can watch the performers closely

C.they are of a sweaty，tangible humanity and a like of enticing simplicity

D.it is much easier for their performers to make eye-contact with their audience

4.In the fourth paragraph，the author gives a detailed description of“La Vie”in order to____.

A.imply that Spiegel world is characterized by suggestive sexy scenes and is mainly oriented to the adults

B.showcase the fact that the performance is sexually attractive，but far from tawdry

C.demonstrate the profound meaning conveyed by the surface of the performance

D.give a general impression of the specific performance and illustrate that people should not be deluded by the representation

5.Which one of the following statements is TRUE of the performances staged in Spiegel tents？

A.Only two families in Belgium and the Netherlands know how to give such performances.

B.The performances are characteristic of erotic shows.

C.The performances are always given with an explicit motif.

D.The performances are mainly given to the mass rather than the elite.

Passage 4

A line of water bottles that had become a symbol of environmental responsibility has been removed from the shelves of Canada’s leading outdoor gear retailer over concerns about a chemical used in its manufacture.

The Mountain Equipment Co-op，which is based in Vancouver，British Columbia，removed the bottles，sold under the brand name Nalgene，and other polycarbonate containers from its 11 large-scale stores on Wednesday.The retailer said that it would not restock the bottles，which are made by Nalge Nunc International in Rochester，a unit of Thermo Fisher Scientific，until Health Canada completed a review of bisphenol-a，or B.P.A.，a chemical used to make hard，transparent plastics as well as liners for food cans.“We’ve been following the B.P.A.issue for at least three years，”said Tim Southam，a spokesman for Mountain Equipment.“The decision we’ve taken this week does not mean that polycarbonate products will never return to our stores.We’re just seeking some certainty about this chemical.”

Church and environmental groups in Canada have mounted campaigns against bottled water because of concerns about the huge amount of plastic used in containers.As a result，the reusable Nalgene bottles have become ubiquitous on college campuses and elsewhere.

Polycarbonate plastic，which can only be produced by using B.P.A.，creates bottles that are transparent and almost as hard as glass，but particularly shatter-resistant.Recently，however，the use of B.P.A.-based plastics in food containers has been questioned in Canada by Environmental Defence，a Toronto-based group. Environmentalists in the United States are also raising concerns about the chemical.Last year，San Francisco’s board of governors passed a local law banning the use of the chemical in children’s products.B.P.A.was removed from the ordinance before it went into effect，however，after an industry lawsuit.Critics point to studies dating back to 1936 showing that the chemical can disrupt the hormonal system.

While there is little dispute about that，the plastics industry，supported by several studies from government agencies in Japan，North America and Europe，contends that polycarbonate bottles contain very little of the chemical and release only insignificant amounts of B.P.A.into the bodies of users.“Rarely has a chemical been the subject of such intense scientific testing and scrutiny，and still，important agencies across the globe agree that there is no danger posed to humans from polycarbonate bottles，”Tom Cummins，the director of research and development at Nalge Nunc，said in a statement.

Rick Smith，the executive director of Environmental Defence，said that a paper published by 38 scientists after a government-sponsored conference in the United States found that the lack of research on the effects of B.P.A.on humans was a concern that required further investigation.Steven G.Hentges，the executive director of the American Chemistry Council’s polycarbonate group，takes issue with that report’s worries and points to a separate expert panel report published by the United States Department of Health and Human Services last month.In its 396-page report，which looked only at the impact of B.P.A.on reproduction，the panel said it had“negligible concern”about the chemical’s effect on adult reproductive systems but raised some concerns about its impact on children and pregnant women.

1.The word“ubiquitous”（Paragraph 3）most probably means____.

A.omnipresent B.popular

C.common D.usual

2.Which one of the following statements is TRUE of the local law passed by San Francisco’s board of governors？

A.This law forbade the use of B.P.A.in food containers for children.

B.This law was not enforced because of an industry lawsuit that was against the use of B.P.A.

C.This law was revised to allow B.P.A.to be used in children’s products.

D.This law went into effect before B.P.A.was removed.

3.According to Tom Cummins，which one of the following is NOT true of B.P.A.？

A.B.P.A.is rarely tested and scrutinized so intensely.

B.The testing and scrutiny done to other chemicals are no comparison with that to B.P.A.

C.That polycarbonate bottles containing B.P.A.are not dangerous to humans is supported by multiple evidence.

D.Polycarbonate bottles containing B.P.A.can be used safely by humans.

4.From the separate expert panel report it can be inferred that____.

A.B.P.A.has no effect on reproduction

B.B.P.A.has trifling impact on children and pregnant women

C.B.P.A.has trifling impact on adult reproductive systems

D.B.P.A.has great effect on reproduction

5.The author’s attitude to the use of Nalgene bottles is____.

A.negative B.positive

C.biased D.unclear

Passage 5

On the face of things，a fall in the number of people infected with HIV（the virus that causes AIDS）from 39.5m to 33.2m over the course of a single year，as reported in this year’s AIDS epidemic update from the World Health Organisation（WHO）and UNAIDS，should be cause for rejoicing.Indeed，it is，for it means there are fewer people to treat，and fewer to pass the infection on，than was previously thought.But the fall is not a real fall.Rather，it is due to a change in the way the size of the epidemic is estimated.

If you factor in that change，the number of infected individuals has actually risen since last year，by 500，000.Yet even that is not necessarily bad news in the paradoxical world of AIDS.As treatment programmes are rolled out around the world，death rates are falling.According to the revised figures，the lethal peak，of 2.2m a year，was in 2005.Now the figure is 2.1m.Since the only way for an infected person to drop out of the statistics in reality（as opposed to by sleight of statistical hand）is for him to die，such increased survivorship inevitably pushes up the total size of the epidemic.

The best news of all，however，is that the new figures confirm what had previously been suspected—that the epidemic has peaked.The highest annual number of new infections around the world was 3.4m in 1998.That figure has now fallen to 2.5m.

Both the change in the death rate and the change in the infection rate are partly a consequence of the natural flow and ebb of any epidemic infection.But they are also a reflection of the hard graft of public-health workers in many countries，who have persuaded millions of people to modify or abandon risky behaviour，such as having unprotected sex，as they have also created the medical infrastructure needed to distribute anti-retroviral drugs that can keep symptoms at bay in those who do become infected.

The revision of the figures is mainly a result of better data-collection methods， particularly in India（which accounts for half the downward revision）and five African countries （which account for another fifth）.In India many more sampling points have been established， and in all countries better survey methods，relying on surveyors knocking on doors rather than asking questions at clinics，have gathered data from more representative samples.

Sceptics will feel vindicated by the revision.They have suspected for a while that the older survey methods were biased，and that the inflation thus produced was tolerated because it helped twang the heart-strings of potential donors.However，the structures for collecting and distributing money to combat AIDS are now well established，and accurate data are crucial if that money is not to be misdirected.The new information also means that the goal of treatment for all who need it will be easier and cheaper to achieve.The WHO and UNAIDS are planning to publish a report on the matter early next year，but Paul De Lay，UNAIDS’s director of evidence，monitoring and policy，says that the financial requirements for 2010 will probably be about 5%less than previously estimated，and that by 2015 that figure will have risen to 10%.Good news for everyone，then，donors and sufferers alike.

1.Though the number of infected individuals has risen，it is still worth rejoicing because____.

A.the number of people who are dying from AIDS has decreased

B.the total size of the epidemic is shrinking to a significant extent

C.it is only a rise in the sense of statistics，instead of a real number

D.in the paradoxical world of AIDS bad news can turn out to be good news

2.About the changes in the death rate and the infection rate of HIV，which one of the following statements is NOT true？

A.Any epidemic will naturally have such changes.

B.They are mainly caused by the new statistic methods.

C.They clearly mirror the essential achievements of public-health workers.

D.The death rate has been greatly suppressed due to massive implementation of treatment programmes.

3.The word“vindicated”（Line 1，Paragraph 6）most probably means____.

A.confused B.clarified

C.doubting D.annoyed

4.By 2015，the financial requirements will____.

A.have risen by 10%more than what was previously estimated

B.be 10% of what was previously estimated

C.be 10% less than previously estimated

D.be 15% less than previously estimated

5.Towards the revision，the author’s attitude can be said to be____.

A.negative B.positive

C.indifferent D.neutral

Passage 6

Infertility is normally seen as a private matter.If a couple are infertile and wish they were not，that is sad.But there is understandable resistance in many countries to the idea that treatments intended to deal with this sadness—known collectively as assisted reproductive technologies，or ARTs—should be paid for out of public funds.Such funds are scarce，and infertility is not a life-threatening condition.

However，two papers presented to the“State of the ARTs”conference held earlier this month in Lyon argue that in Europe，at least，there may be a public interest in promoting ARTs after all.The low fertility rate in many of that continent’s more developed countries means their populations are ageing and shrinking.If governments want to change this，ARTs—most significantly in-vitro fertilisation（IVF）—could offer at least part of a way to do so.

As the conference heard，IVF does seem to be keeping up the numbers in at least one country.Tina Jensen of the University of Southern Denmark has just finished a study of more than 700，000 Danish women.She found that young women in Denmark have a significantly lower natural conception rate than in past decades.That is partly，but not entirely，because they are having their children later in life.The rest of the cause is unknown，though reduced sperm quality in men may be a factor.Whatever the cause，she also found that the effect has been almost completely compensated for by an increasing use of ARTs.Denmark’s native population is more or less stable，but some 3.9%of babies born there in 2003 were the result of IVF.The comparable figure for another northern European country，Britain，was 1.5%.

Without IVF，then，the number of Danes would be shrinking fast.That may not have something to do with the fact that in Denmark the taxpayer will cover up to six cycles of IVF treatment.In Britain，by contrast，couples are supposed to be entitled to three cycles.In practice，many of the local trusts that dish the money out do not pay for any cycles at all. Jonathan Grant，the head of the Cambridge branch of the Rand Corporation（an American think-tank），believes this is shortsighted.His paper showed that if Britain supported IVF at the Danish level then its birth rate would probably increase by about 10，000 a year.

The cost of offering six cycles to couples（and doing so in practice，rather than just in theory）would be an extra£250m-430m a year.That is not trivial，but Dr.Grant reckons it is cheaper than other ways of boosting the birth rate.Some countries，for example，have tried to bribe women into having more children by increasing child benefits.According to his calculations，raising such benefits costs between£50，000 and£100，000 a year for each additional birth procured.Ten thousand extra births each year would thus cost between £500m and £1 billion.

There are，of course，some disadvantages to promoting IVF.In particular，women who use it tend to be older than those who conceive naturally，and that can lead to congenital problems in their children.But if the countries of Europe do wish to keep their populations up，making IVF more widely available might be a good way of doing so.

1.According to the text，the public’s opinion on the infertility treatments is that____.

A.the treatments should be paid for out of public funds

B.the treatments are not so compulsory as they consume the limited public funds

C.the treatments are not necessarily only paid for out of public funds

D.the public is not obliged to pay for such treatments of no urgent nature

2.According to the study conducted by Tina Jensen，which one of the following statements is TRUE？

A.ARTs have reversed the tendency of the decreasing population in Denmark.

B.Danes’problem of low natural conception has been completely counterbalanced by the widely use of ARTs.

C.The population of Denmark is not decreasing after the adoption of ARTs.

D.IVF has played an essential role in Denmark in terms of keeping up the number of its population.

3.From the paper of Dr.Grant，it can be inferred that____.

A.the cost of offering six cycles of IVF to couples is not high at all

B.IVF treatment is an economical way of solving population shrinking

C.Britain does not promote adopting IVF to boost the birth rate

D.encouraging women to bear more babies by bonus is not so efficient to solve the problem of population shrinking

4.The word“congenital”（Line 2，Paragraph 6）most probably means____.

A.innate B.instinctive

C.cerebral D.acquired

5.According to the passage，the author’s attitude towards promoting in-vitro fertilization can be said to be____.

A.supportive B.opposing

C.ambiguous D.objective

Passage 7

Back in 2000，Steve Ballmer，Microsoft’s chief executive，described a grand vision for the future of health care.One day，he said，everyone would have a secure and private website on the Internet on which their doctors could post their“scans，lab results，test results，visit minutes”，and to which the owner could grant certain people access，to view some or all of that information.His ideas met with guffaws from the old lags of the industry，who have seen many fancy schemes for electronic medical records fall flat.America’s health sector is simply too balkanised and too paper-based to stitch together easily in digital form.Even Mr.Ballmer conceded back then that he was searching for the“holy grail”of healthcare.

And yet，after years of frustration and furious development work，Microsoft now believes it has realised Mr.Ballmer’s dream.On October 4th，the software giant was poised to unveil its new health-information product at a big event in Washington，DC.It is called the Health Vault，in keeping with Microsoft’s promise to make storing data on the Internet just as secure as keeping it in a bank.Health Vault will store all its customers’health data，ranging from test results to doctors’reports to daily measurements of weight or blood pressure，online. Individuals then have access to those records anytime，anywhere，via the Internet—a great boon for those who travel a lot.Medical offices and hospitals who sign up for the service could easily send test results in digital form to the vault，and patients could authorise them in turn to have access to various，carefully circumscribed bits of their personal data.

Microsoft was also set to announce this week that several dozen manufacturers， hospitals and charities have signed up for Health Vault.Big names including the American heart，diabetes and lung associations，the New York-Presbyterian Hospital，and Omron and Texas Instruments，in addition to various firms devoted to the craze for“wellness”，are all now on board，and are expected to announce products and services shortly.If the software giant has really found a hacker-proof way of storing records online，then the benefits of Health Vault are clear.But use of the vaults will be free both for the individuals that sign up for them and for the vendors and doctors that provide services based on the information they contain. So how will Microsoft make any money？

Sean Nolan of Microsoft explains that the business model depends on one thing： targeted search.Microsoft is betting that people will use its Health Vault Search to find out about their ailments.This service relies on an approach known as“vertical search” which attempts to provide more relevant results than generalist search engines like “Google”and“Yahoo”！by specialising in a particular field.The firm’s recent acquisition of Medstory，a vertical-search engine focusing on health care，has given it a boost in this area.

Health Vault’s search engine would definitely work better than those of rival sites if it could examine users’health records and past queries，and thus provide the responses that are most relevant to each individual’s situation.But in order to attract any users in the first place，Microsoft has promised to enforce strict privacy rules.These would preclude such data-mining.

1.The old lags of the industry did not think highly of Ballmer’s scheme because____.

A.Ballmer’s scheme sounded too fantastic and far-fetched to be true

B.Ballmer lacked technology proof to back up his ideas

C.they had witnessed too many failures of attempts to realize such schemes

D.America’s health sector is too stubborn and is reluctant to change for the digital

2.Which one of the following statements is NOT true of Health Vault？

A.Individuals can have access to the medical records of anybody anytime via the Internet.

B.Those who travel a lot will greatly benefit from services of Health Vault.

C.Hospitals who sign up for the service could improve their efficiency by Health Vault.

D.Health Vault is software invented by Microsoft.

3.The main problem of Health Vault is____.

A.that it will be difficult for Vault to make profit during the beginning phase

B.that the software may be trapped in the dilemma of customer privacy and convenient data search

C.that it has to adopt the“vertical search”which is not the company’s strength

D.that Microsoft does not have powerful search engines as Google and Yahoo！do

4.Microsoft will make money in Health Vault by____.

A.attracting customers with the enforcement of strict privacy rules

B.providing a charging platform for the communication of patients and hospitals

C.cooperating with big hospitals and charities by providing useful customer information

D.providing highly specialized service with high efficiency

5.Compared with Google and Yahoo！，the advantage of Health Vault Search is____.

A.that its technology far more advanced than that of the other two

B.that it is more effective for those who need special information

C.that it specializes on the information of ailment diagnosis

D.that its business model is more promising and profitable

Passage 8

Most cells are transparent—in other words，they are not very good at reflecting or absorbing light.To look at them under a microscope thus requires trickery.Many of these tricks kill the cells，and even those that keep them alive look only at slices through each cell，rather than seeing the whole thing in three dimensions.

Michael Feld，of the Massachusetts Institute of Technology，and his colleagues，think they can change that.They have invented a way to look at cells that are still alive.Moreover，they can do so in three dimensions.Their method is called tomographic phase microscopy，and it is reported in this week’s Nature Methods.Instead of relying on absorbed or reflected light，Dr.Feld’s technique celebrates transparency by looking at light that gets through unaltered.It does so by measuring a property called the refractive index.

This index measures the speed of light in a material.（Light zips along at the actual“speed of light”，faster than which nothing can go，only when it is travelling through a vacuum.）The different components of a cell，though transparent，have different refractive indices.Dr.Feld and his team therefore set out to map what these differences are，with a view to using them to distinguish between cellular components.

To measure the refractive indices of different parts of a cell they use a technique called interferometry，which involves splitting a beam of light in two.One half，known as the object beam，passes through the cell；the other is directed along a different path and acts as a reference.The length of the reference path is such that if no sample is present，the two daughter beams will be as perfectly in phase when they meet as they were when they were separated.The crests and the troughs of their waves will reinforce each other，and the result will be brightness.The more that the light passing through the sample is slowed down，however，the more the two beams will be out of phase.Crest will fall on trough，and the result will be darkness.It is this phase shift that gives Dr.Feld’s new form of microscopy its name.

A single pair of beams does not，however，produce a useful image.To do that requires scanning the object beam through the target about a hundred different ways.From the refractive index of each path it is possible—with the application of some suitably crunchy computing power—to produce a three-dimensional image.

To test his idea，Dr.Feld looked at cervical-cancer cells.If you identify this cancer early，the patient will probably survive.Miss it，and she will die.Dr.Feld wondered if the changes that occur during cancer would show up using his new method.They did，in a part of the cell called the nucleolus.This is the place where the components of protein factories are made.Since cancer cells grow rapidly，and thus have a high demand for proteins，it was a likely place to expect changes.

Dr.Feld also has plans to use beams of different colours，since each colour has a slightly different refractive index in a given material.That would provide extra data for the computer to chew on，and probably result in better pictures.With enough pictures，Dr.Feld’s technique may make biology as transparent as the cells it studies.

1.Tomographic phase microscopy is different from the other tricks that look at cells in that____.

A.the light that gets through the cells is unaltered in tomographic phase microscopy

B.it does not require the trickery to kill cells

C.it is not dependent on absorbed or reflected light

D.it could see all the components of the cells from three dimensions

2.Which one of the following statements is TRUE of the speed of light in materials？

A.Light runs the fastest when it is passes through transparent materials in the real world.

B.The speed of light can only be precisely measured when the light is travelling in vacuum.

C.The speed of light in any material is slower than the actual“speed of light”.

D.The speed of light shifts when the light travels through different cells.

3.The result of darkness in the technique of interferometry implies that____.

A.there is no light passing through the sample

B.the refractive index of the sample is very great

C.the speed of the light passing through the sample is very slow

D.the two daughter beams weaken each other

4.Dr.Feld’s method could be applied into identifying cancer early by____.

A.detecting changes of refractive indices in the components of protein factories

B.finding out the changes of the refractive indices in some parts of the cervical-cancer cells

C.examining the changes of the refractive indices in the nucleolus

D.identifying the changes of the refractive indices in part of the nucleolus of the cancer cells

5.The best title of the passages could be____.

A.Image of the Transparent Cells

B.New Technique of Celebrating Transparency

C.Refractive Indices of the Transparent Cells

D.New Method of Detecting Cancer Cells

Passage 9

For a Nobel laureate，the molecular biologist Max Perutz made a lot of mistakes.His science was strewn with assertions that were not supported by the sparse evidence he had gathered.No matter.He was eventually right about the important things—and gentleman enough to concede his errors.

With bloody-minded persistence，Perutz mastered the painstaking task of analysing images of haemoglobin，the component of blood that carries oxygen.This was by no means feat：a molecule of haemoglobin consists of thousands of atoms and，at the time，only simple structures of tens of atoms had been mapped.It was for this work that Perutz was awarded the Nobel prize in chemistry in 1962.But his triumphal announcement of the correct structure of haemoglobin was by no means his first solution to the problem：he had previously claimed all sorts of unlikely arrangements，backing down each time a colleague spotted a fatal flaw.

Even when he did finally hold the secret to why blood supports life，he did not piece together the evidence to produce the ultimate result.Indeed，Perutz was furious when a junior researcher saw how the final piece fitted and could not resist popping it into its slot， completing what Perutz viewed as his jigsaw puzzle.Nevertheless，it was Perutz who had gathered all the pieces and who ensured，in the end，that they were correctly assembled.

Perutz was long the outsider.Of Jewish descent，he was a lapsed Catholic by religion. He left his native Austria in 1936，two years before Hitler annexed it.The outbreak of war saw him expelled to Canada as an enemy alien.On returning to Cambridge，he was not welcomed by his college.It was only after he won the Nobel Prize that he felt accepted as an Englishman，despite having been naturalised as a British subject 20 years earlier.

As a scientist，too，Perutz was always on the fringe.His field of endeavour，X-ray crystallography，was neither physics nor maths nor chemistry nor biology but a combination of these.As often happens to researchers working in interdisciplinary areas of science，his progress was impeded by an establishment that sought to promote existing subjects.He lived from grant to grant，each lasting a matter of months.Nevertheless，he managed to establish the unit in which James Watson and Francis Crick elucidated the double helix structure of DNA. A decade later，a whole institute was established under him.

Georgina Ferry’s biography captures not only the scientific advances made by Perutz but also his curious personal qualities.A skinny，sickly and，for much of his life，skint individual，Perutz is an unlikely hero.He was demanding—his diet required him to eat black bananas，even in February—and he was unselfconscious in ensuring that his elaborate needs were met.He was also naive in insisting that scientific reasoning would trump political thought and religious teaching.

Ms Ferry portrays his foibles sympathetically.Perutz used to complain that，although he was famous，few people knew what it was he had achieved.By combining scientific with personal anecdotes，her book goes a good way towards redressing that balance.

1.Max Perutz won the Nobel prize though he made a lot of mistakes because____.

A.his important contribution outweighed those marginal mistakes

B.he made assertions not based on the sparse evidence he had gathered

C.he could always reach the correct conclusion in the end

D.he was brave enough to admit his mistakes and strived for improvement

2.Which one of the following statements is TRUE of Perutz’s task of analyzing the structure of hemoglobin？

A.Perutz successfully worked out the structures of all the different arrangements of atoms of hemoglobin.

B.It is not Perutz who had first provided an answer to the correct structure of hemoglobin.

C.It is in fact Perutz’s colleague who had sorted out the solution to the problem of hemoglobin’s structure.

D.Perutz had worked diligently on the divergences between himself and his colleague in analyzing the structure of hemoglobin.

3.Perutz was very angry with the junior researcher who popped the final piece into its slot because____.

A.the researcher asserted that what Perutz viewed was only jigsaw puzzle

B.the researcher pointed out that Perutz did not piece together the evidence to prove the final result

C.the researcher passed off the secret to why blood supports life as his own idea

D.the researcher pieced together the evidence to work out the final result

4.Perutz’s progress was interrupted by an establishment because____.

A.the subject he studied did not belong to any of the conventional disciplines

B.his study threatened existing subjects by promoting interdisciplinary areas of science

C.that establishment prevented him from receiving adequate and long-term funds

D.he was diverted to the cause of setting up a brand new institute

5.The word“redressing”（Paragraph 7）most probably means____.

A.remedying B.rectifying

C.re-adjusting D.reversing

Passage 10

In a world where sight and sound seem to reign supreme，all it takes is a cursory glance at the size of the perfume industry to realise that smell matters quite a lot，too.Odours are known to regulate moods，thoughts and even dating decisions，which is why any serious romantic will throw on the eau de toilette before going out for a night on the town.Yet in all these cases，those affected are aware of what they are smelling.Unlike the media of sight and sound，in which subliminal messages have been studied carefully，the potential power of subliminal smells has been neglected.

Wen Li and her colleagues at Northwestern University in Chicago are now changing that.In particular，they are investigating smells so faint that people say they cannot detect them.The idea is to see whether such smells can nevertheless change the way that people behave towards others.

Dr.Li’s experiment，the results of which have just been published in Psychological Science，employed 31 volunteers.These people were exposed to three different odours at low concentration.One was the fresh lemon scent of citral.The second was the neutral ethereal perfume of anisole.The third was the foul sweaty smell of valeric acid.And the concentrations really were low.In the case of valeric acid，for example，that concentration was seven parts per trillion—a level only just detectable by bloodhounds.As a control，Dr.Li used a mineral oil that has no detectable smell at any concentration.

The participants were asked to sniff a jar containing either one of the three odours or the scentless oil，and then press a button to indicate whether they thought the jar smelled of anything.Immediately after that，a picture of a face would appear on a screen in front of them for just over a second.Each participant was asked to rate the face’s“likeability”.

Dr.Li found that the odours helped shape people’s judgments about the faces when their responses indicated that they had not smelled anything.When someone had been exposed to valeric acid，for example，he tended to react negatively to a face.Exposure to citral，by contrast，made that face seem，on average，more friendly.（Obviously，the same face was not shown to any given participant more than once.）Even more intriguing，however，was that when participants did consciously perceive a smell，its effect on face-perception disappeared.

What is going on is unclear.If smells can carry useful information about personality（which is possible），then the effect would be expected to be the same whether or not the chemical in question is detected subliminally.If they do not carry such information，then it is hard to see what use the subliminal reaction is.Nevertheless，it is there.

The findings do，however，demonstrate what might be a powerful method of manipulation.Indeed，Dr.Li considers the potential uses to be vast.Business meetings might be made more pleasant by releasing appropriate fragrances into the air in unsmellable amounts.Conversely，fights might be started by putting people in the presence of a faint foul odour.Advertising hoardings might benefit from a little olfactory tweaking and cinema audiences could be reduced to floods of tears at the appropriate moment.The sweet smell of success might，in other words，actually be undetectable.

1.Dr.Li is carrying out such an investigation in order to____.

A.find out how smells regulate moods in a subtle and nuanced way

B.prove that smell plays an equally important role in daily life as that of sight and sound

C.find out if people are sensitive to faint smells

D.find out if faint smells could influence people’s judgment of others

2.The mineral oil is used in Dr.Li’s experiment to____.

A.control the concentration of odors to a slightly detectable degree

B.act as a group of comparison with that of the other smells

C.regulate the participants’moods by decreasing the smell’s concentration

D.protect the participants from losing the sense of smell

3.The word“likeability”（Line 4，Paragraph 4）most probably means____.

A.similarity B.likeness

C.loveliness D.likelihood

4.When the participants consciously smelt the valeric acid，they tended to____.

A.make negative judgment to a face

B.make positive judgment to a face

C.make biased judgment to a face

D.make fair judgment to a face

5.From Dr.Li’s experiment，it can be inferred that____.

A.one’s reaction to subliminal smells reflects useful information about his or her personality

B.subliminal smells can influence people’s interaction with each other

C.subliminal smells have no effect on people’s conscious face-perception

D.subliminal smells turn out to be a means of powerful manipulation in terms of business success

Passage 11

A boy or a girl？That is usually the first question asked when a woman gives birth. Remarkably，the answer varies with where the mother lives.In rich countries the chances of being a boy are about 5%higher than in poor ones.Equally remarkably，that figure has been falling recently.Several theories have been put forward to explain these observations.Some argue that smoking plays a role，others that diet may be important.Neither of these ideas has been supported by evidence from large studies.But new research points to a different factor：stress.

Strange as it might seem，the terrorist attacks of September 11th 2001 shed light on the enigma.Studies noting the sex of babies conceived in New York during the week of the attacks found a drop in the ratio of males to females.That is consistent with earlier studies，which revealed a similar shift in women who became pregnant during floods and earthquakes and in time of war.Moreover，a study carried out eight years ago by researchers at the University of Aarhus，in Denmark，revealed that women who suffered the death of a child or spouse from some catastrophic illness around the time they conceived were much more likely to give birth to girls than to boys.

Taken together，these results suggest that acute stress to a woman at the time of conception shifts the sex ratio towards girls.However，Carsten Obel，a researcher at Aarhus who was not involved in the earlier study，wondered if the same might be true of chronic stress too.In a paper just published in Human Development，he shows that it is.

Dr.Obel used a set of data collected between 1989 and 1992.During that period 8，719 expectant mothers were asked to fill in questionnaires that inquired，among other things，about their level of stress.Dr.Obel found that the more stressed a mother had been，the less chance she had of having given birth to a boy.Only 47%of children born to women in the top quartile of stress were males.That compared with 52%for women in the bottom quartile.Dr.Obel suspects the immediate cause is that male pregnancies are more likely to miscarry in response to stress than female pregnancies are，especially during the first three months.However，that is difficult to prove.More intriguing，though，is the ultimate cause，for he thinks it might be adaptive，rather than pathological.

That is because the chances are that a daughter who reaches adulthood will find a mate and thus produce grandchildren.A son is a different matter.Healthy，strapping sons are likely to produce lots of grandchildren，by several women—or would have done in the hunter-gatherer societies in which most human evolution took place.Weak ones would be marginalised and maybe even killed in the cut and thrust of male competition.If a mother’s stress adversely affects the development of her fetus then selectively aborting boys，rather than wasting time and resources on bringing them to term，would make evolutionary sense.

That，in turn，would explain why women in rich countries，who are less likely to suffer from hunger and disease，are more likely to give birth to sons.That this likelihood is，nevertheless， falling suggests that rich women’s lives may be more stressful than they used to be.

1.The author begins the passage by____.

A.presenting an argumentation B.explaining a phenomenon

C.raising a question D.making a comparison

2.The ratio of giving birth to a boy is falling in rich countries because____.

A.the terrorist attacks of September 11th 2001 exerted huge negative impact

B.women are facing greater pressure now than in the past

C.women are under new pressure now which they seldom faced in the past

D.male pregnancies are more easily to miscarry

3.Which of the following can explain Dr.Obel’s opinion that the ultimate cause is adaptive rather than pathological？

A.47% of children born to women in the top quartile of stress were males while 52% in the bottom quartile.

B.Women in rich countries are more likely to give birth to boys.

C.Women selectively abort boys rather than waste time and resources on bringing them to term for fear of male competition.

D.Women who suffer from calamity in conception are more likely to give birth to girls.

4.Women in the hunter-gatherer societies are more likely to give birth to daughters because____.

A.they agree that giving birth to daughters is beneficial in the evolutionary sense

B.sons are likely to produce lots of grandchildren with several women

C.they think it is a better practice for a daughter to produce grandchildren with only one mate

D.they think bringing sons to term is wasting time and resources

5.From this passage，we may draw a conclusion that____.

A.acute stress is more likely to cause women to choose aborting boys than chronic stress

B.stress to a woman at the time of conception，whether acute or chronic，will shift the sex ratio towards girls

C.more girls will be born in the future because today’s women，in both rich and poor countries，suffer from increasing pressure

D.chronic stress is more decisive in influencing the women’s pregnancies

Passage 12

Numbers get a bad press.Almost alone of the academic disciplines，mathematics is one where expressions of ignorance are more of a boast than a shameful admission（imagine admitting at a dinner party that you can’t read）.Yet numbers are more important than ever. They are the language of most of science and much of government，two forces that do much to shape people’s lives.They are the nervous system of any modern country，marshalled in support of arguments over everything from defence to which diseases should be treated.

Happily for the number-shy，help is at hand.A book about numbers and how to interpret them doesn’t sound like interesting bedtime reading.Yet in the hands of Michael Blastland and Andrew Dilnot，respectively producer and presenter of“More or Less”，a BBC radio programme on the subject，that is what it becomes.

The chapters proceed from simple concepts to more complicated ones，starting with the simples of all：working out how big a number is.That is harder than you might think.The British government’s promise to spend£300m（$600m）over five years on child-care looks impressive at first glance.Only after working through the calculations does one realise that it amounts to only £1.15 a week for every family.The authors avoid a hectoring tone.Their prose is light-hearted and never condescending.Amusing（or occasionally frightening）examples make theoretical arguments instantly accessible.The authors point out that most people have a higher-than-average number of feet（it takes only a single man with one foot to bring the average below two）.Incomes are the other way around：thanks to a few billionaires，most people earn less than the average.

Later on，trickier and more emotive subjects are tackled.Much of the second half is taken up with the devilishly tricky business of trying to extract causation from correlation.One such issue is the so-called“cancer clusters”.A mobile-phone mast is erected in a village.Soon after，cancer rates rise to several times the national average.But masts are common，and some villages are bound to develop high cancer rates through nothing more sinister than sheer bad luck.Proving correlation is easy，but proving causation—despite how obvious the links may seem—is not.The authors make the sobering point that mortality rates for doctors vary so much that，even if he had been constantly monitored，Harold Shipman（a British doctor who murdered at least 200 patients）would have racked up a body-count of several dozen before coming to official attention.

The central problem，as the authors admit，is that numbers can often be deeply counter-intuitive.Individuals find it difficult to cope with the vast quantities of cash consumed by a modern nation state，and everyday rules of thumb can sometimes lead to utterly wrong conclusions.That is what makes this book so valuable：it provides a reliable guide to a treacherous subject，giving its readers the mental ammunition to make sense of official claims.That it manages to make them laugh at the same time is a rare and welcome feat.

1.Which one of the following statements is TRUE of status quo of mathematics？

A.One is cracking oneself up when expressing ignorance of mathematics.

B.Mathematics is only a discipline to tolerate the shame of knowing nothing about numbers.

C.The shame of admitting that you can not read at a dinner party is paramount of admitting that you do not know about mathematics.

D.Expression of ignorance in mathematics is a boast not only in the academic disciplines but also in other fields.

2.The style of“More or Less”by Michael Blastland and Andrew Dilnot can be described as____.

A.detailed and accessible B.technical and illuminating

C.professional and inviting D.theoretical and humorous

3.The author of the article uses the example of average number of feet and average income to demonstrate that____.

A.to correctly understand the meaning of numbers is sometimes very tricky

B.people can understand better about statistical data by comparing them with most common phenomenon

C.the book helps people learn about the secret of numbers through interesting and daily examples

D.the way of calculating average income is the opposite to that of calculating the average number of feet

4.Some villages develop high cancer rates through sheer bad luck other than masts because____.

A.they could not sense any link between these two phenomena

B.they can only find some vague correlation between them without solid evidence

C.there are not enough proofs to demonstrate that masts could raise cancer rate

D.they could not deduce a reasonable relation of the cause and effect on the concerning issues

5.According to the authors of“More or Less”，the main point they want to demonstrate is that____.

A.numbers are very difficult to understand

B.numbers could be cheating in most occasions

C.numbers can be subtly sensed by intuition

D.numbers could make people’s minds more reasonable

Passage 13

Everyone is interested in whether different foods or nutrients affect our odds of getting diseases like cancer or of developing risk factors for those diseases，such as too much weight or high blood pressure.But there are many barriers to studying dietary change，which is why we still have no easy answers to the question of what，exactly，we should eat to be at our healthiest.It’s also why you can be forgiven for often feeling whipsawed by headlines：Is coffee good or bad？What about alcohol，garlic，or chocolate？

This week researchers reported in the Journal of the American Medical Association that breast cancer survivors who cram their diets with fruits and vegetables are no more likely to escape a recurrence than women who stick to the usual five-a-day recommendation.Does that mean fruits and vegetables don’t protect against cancer？No—just that in this specific group of women with breast cancer，the extra greens and additional apples didn’t seem to help.

We asked researchers to explain why studies involving dietary changes are so hard to do—and what consumers should keep in mind when they read about them.Here’s what the experts said：

Most diet studies take place in the real world.That means study subjects are keeping diaries of what they eat as they go rather than having their intake strictly controlled by someone else.You can give them meal advice，counseling，and how-to books up to their ears，but at the end of the day，they are on their own when it comes to what they put in their mouths.It’s easier to get people to add something—like garlic，in the form of tasty sandwich spreads，or dark chocolate—than to take something away；no wonder a recent study comparing low-fat and low-carb diet plans found that almost no one was sticking to them by the end.

In studies focusing on diet，including the recent study on breast cancer recurrence，the amount of calories subjects reported eating would have caused them to lose far more weight than they actually did lose.The misreporting isn’t necessarily vicious，but the inaccuracies add up.Say you’re phoned about your daily intake on a day when it was someone’s birthday at work and you had a slice of cake.You may not report it，thinking that a typical day wouldn’t include the cake...forgetting yesterday’s“special occasion”piece of pizza，and the Big Gulp of the day before.Or，despite the portion size guides you get，you characterize your bagel from the deli as a 4-ounce standard serving when a 4-ounce bagel hasn’t been sighted in any major city for a decade.

“You can’t put a camera in everyone’s belly and see exactly what they ate，”says Christopher Gardner，a nutrition scientist at the Stanford Prevention Research Center who has recently published research on garlic and diet plans.You can get around this in some studies by taking objective measurements.Weight，for example，or if you’re assessing intake of fruits and veggies，you can measure the level of pigments called carotenoids in the blood.In the breast cancer study，blood tests showed that the study subjects actually did eat more fruits and veggies（carotenoid concentration was 73 percent higher in those women after one year and 43 percent higher after four years）.But objective measures can’t definitively nail down whether someone is eating nutrients in certain proportions.

1.One can be forgiven for feeling whipsawed by those headlines because____.

A.there is no solid and convincing scientific hypothesis on these subjects

B.the question about what the healthiest food is has no answers(https://www.daowen.com)

C.opinions on these subjects are quite contradictory

D.there is no authoritative answer to these questions

2.Which one of the following statements is TRUE of the conclusion of the study on breast cancer recurrence？

A.Women who stick to the five-a-day recommendation are less likely to have a recurrence.

B.Women who eat extra greens and vegetables are less likely to escape a recurrence.

C.Women could not depend on fruit diet to avoid the breast cancer recurrence.

D.Fruits and vegetables are no good to women with breast cancer.

3.From the results of the studies focusing on diet，it can be inferred that____.

A.the amount of calories set in diet could not help people to lose weight

B.people are reluctant to take part in such studies

C.it is difficult to get valuable conclusion from these studies

D.this kind of studies is not objective enough

4.The fact that a 4-ounce bagel hasn’t been sighted in any major city for a decade implies that____.

A.you should re-examine the standard size of the food you intake

B.you tend to give an inaccurate report of your actual diet

C.you fail to cooperate with the doctor by false record of your daily food

D.you make a mistake in noting down the size of standard serving

5.The limitation of the objective measurements mentioned in the last paragraph is that____.

A.they could only assess the proportion of fruits and veggies study subjects have taken

B.they could not have the subjects follow exactly the food proportion of their diet

C.they could not identify the levels of all the nutrients in patients’blood

D.they could not tell the exact proportions of nutrients study subjects have eaten

Passage 14

If you found yourself in a cocktail bar with a Neanderthal man，what would he say？A good conversation is one of the great joys of being human，but it is not clear just how far back in the hominid lineage the ability to use language stretches.The question of when grunts and yelps turned into words and phrases is a tricky one.One way of trying to answer it is to look in the fossil record for evidence about what modern humanity’s closest relatives could do.Svante Pääbo，of the Max Planck Institute for Evolutionary Anthropology in Leipzig， and his colleagues have done just that.Dr.Pääbo is an expert in extracting and interpreting the DNA of fossils.As he reports in the latest issue of Current Biology，he and his team have worked their magic on a gene called FOXP2 found in Neanderthal remains from northern Spain.The reason for picking this particular gene is that it is the only one known so far to have a direct connection with speech.In 1990，a family with an inherited speech disorder known as verbal dyspraxia drew the attention of genetics researchers.Those researchers identified a mutation in FOXP2 as the cause of the dyspraxia.

Since then FOXP2 has been the subject of intensive study.It has been linked to the production of birdsong and the ultrasonic musings of mice.It is a conservative type，not changing much from species to species.But it has undergone two changes since humans split from chimpanzees 6m years ago，and some researchers believe these changes played a crucial role in the development of speech and language.

If these changes are common to modern humans and Neanderthals，they must predate the separation of the line leading to Homo sapiens from the one leading to Homo neanderthalensis.Dr.Pääbo’s research suggests precisely that：the FOXP2 genes from modern humans and Neanderthals are essentially the same.To the extent that the gene enables language，it enables it in both species.

There has been much speculation about Neanderthals’ability to speak.They were endowed with a hyoid bone，which anchors the tongue and allows a wide variety of movements of the larynx.Neanderthal skulls also show evidence of a large hypoglossal canal.This is the route taken by the nerves that supply the tongue.As such，it is a requisite for the exquisitely complex movements of speech.Moreover，the inner-ear structure of Homo heidelbergensis，an ancestor of Neanderthals，shows that this species was highly sensitive to the frequencies of sound that are associated with speech.

That Neanderthals also shared with moderns the single known genetic component of speech is another clue that they possessed the necessary apparatus for having a good natter.But suggestive as that is，the question remains open.FOXP2 is almost certainly not “the language gene”.Without doubt，it is involved in the control and regulation of the motions of speech，but whether it plays a role in the cognitive processes that must precede talking remains unclear—jokes about engaging brain before putting mouth in gear notwithstanding.The idea that the forebears of modern humans could talk would scupper the notion that language was the force that created modern human culture—otherwise，why would they not have built civilisations？But it would make that chat with a Neanderthal much more interesting.

1.Which one of the following statements is TRUE of Neanderthal men？

A.They are derived from a branch of early Neanderthals called Homo heidelbergensis.

B.They are existent descendant of Homo neanderthalensis.

C.They are Homo sapiens’closest relatives.

D.They are officially named Homo neanderthalensis in the academic circle.

2.Svante Pääbo and his team carried out a study on FOXP2 in order to____.

A.trace the appearance and evolution of the speech ability

B.find out how far back in the hominid lineage the ability to use language stretches

C.find evidence proving the gene which controls the motion of speech

D.identify the crucial changes that had taken place on this gene and the consequent influence

3.The gene of FOXP2 is regarded as a gene with a direct connection with speech because____.

A.it was found that FOXP2 existed in Neanderthal remains from northern Spain

B.it was found that sudden change of FOXP2 may lead to speech disorder

C.it was linked to the production of birdsong and the ultrasonic musings of mice

D.it does not change much from species to species

4.The word“scupper”（Paragraph 5）most probably means____.

A.deny B.defeat

C.demolish D.destroy

5.From the findings of Dr.Pääbo’s research it may be inferred that____.

A.FOXP2 is the gene that enables the speech ability in both humans and Neanderthals

B.the fork separating the line leading to Homo sapiens from that to Homo neanderthalensis is wrong

C.more important genes should be identified which control speech ability and cognitive process

D.the establishment of human civilization as a result of language ability might be false

Passage 15

Britons’most searing memories of their encounter with foot-and-mouth disease in 2001 are of the piles of animals slaughtered to try to stop its spread.Such a draconian policy might have been accepted had the disease been controlled quickly.But its ineffectiveness— more than 6m cows，sheep and pigs were culled before the disease was eradicated—led to widespread revulsion and a government rethink.

Just as in 2001，if an animal is thought to be infected，its herd will be culled and a quarantine zone set up.But this time，unless the disease is stamped out quickly，animals nearby will also be vaccinated to create a“fire-break”across which it is unlikely to travel. Already 300，000 doses of vaccine have been ordered，so that if government vets decide that slaughter alone is unlikely to be effective，they can start vaccinating straight away.

Humans almost never catch foot-and-mouth and it rarely kills the cloven-hooved beasts it affects.But animals produce less milk and meat，so its economic effects are severe.It is also highly contagious：infected livestock produce the virus that causes it in large quantities， and transmit it through saliva，mucus，milk，faeces and even droplets in their breath.

Even so，only countries where foot-and-mouth is endemic，as in parts of Latin America， vaccinate all animals.One reason is cost：the disease is caused by a virus with seven main types and tens of sub-types，with a targeted vaccine needed for each strain and shots repeated，perhaps as often as twice a year.It is also because vaccinating damages exports. Places that are free from foot-and-mouth are unwilling to import vaccinated beasts，or fresh meat from them，because they may still carry the disease.

The fear of being shut out of foreign markets led to the British government’s disastrous foot-dragging over vaccination in 2001.But that same year an outbreak in the Netherlands involving 26 farms was brought under control in just one month by vaccinating 200，000 animals.Though healthy，these beasts then had to be culled so that farmers could return to exporting without restrictions as soon as possible.

Not even eternal vigilance on imports can keep a country free of foot-and-mouth disease：the latest outbreak was apparently caused by a breach of bio-security at the Pirbright laboratory complex in Surrey，where government researchers keep the live virus for vaccine research and Merial，an American animal-health company，manufactures vaccine for export.Human action，accidental or deliberate，seems likely to have been involved.

Ironically，one reason for eschewing vaccination is that although it provides the best hope of dealing with outbreaks，maintaining the capacity to produce vaccine is itself a risky business.Many earlier episodes of foot-and-mouth in countries normally free from the disease have been caused by laboratory escapes；in 1970 a leak from Pirbright’s isolation facilities was fortunately contained.

1.Which one of the following statements is NOT true of the foot-and-mouth disease in Britain in 2001？

A.The disease had never been effectively controlled throughout the event.

B.The policy of slaughtering animals to stop the disease spread proved to be a failure.

C.The slaughtering policy was arousing discontent among the public in Britain.

D.The government failed to take immediate actions of creating fire-break around the infected livestock.

2.The new policy is different from the policy in 2001 in the following aspects EXCEPT.

A.the piles of animals will not be slaughtered as in 2001

B.animals near the infected herb will be injected with vaccine

C.a belt of quarantine with vaccinated animals will be erected

D.it is paying more attention to prevention of the outbreak of the epidemic

3.Only a few countries have all of their animals injected with vaccines because of the following reasons EXCEPT____.

A.it is unnecessary to vaccinate all the animals in the counties in which there are few chances of infecting foot-and-mouth

B.the cost of vaccines against all types of the virus causing the disease is very high

C.vaccinated animals are less welcomed by importing countries

D.the vaccine cost will be rising as types of virus causing the disease are increasing

4.Though vaccinated animals were free from the foot-and-mouth in Britain and Netherlands in 2001，they were still slaughtered because____.

A.they might be more likely to infect the virus than the healthy ones

B.the exporting restrictions were too strict to let these animals pass the customs

C.the farmers were afraid of being deprived of the exporting right

D.the government wanted to regain the former status of exporting animals

5.The outbreak of foot-and-mouth disease may be a result of the following situations EXCEPT____.

A.animals being wrongly or incompletely injected with vaccination

B.importing animals from the countries with the foot-and-mouth-disease

C.leak of the virus during the research experimentation

D.malicious actions by some people with particular purpose

Passage 16

When honey bees began to desert their hives recently，never to return，it threw apiarists into a panic.What appeared to be perfectly healthy adult bees would flee their queen，the young and their food stores.Instead of ransacking the empty hive，other bees would avoid it like the plague.Yet there was nothing obviously wrong.Researchers have now identified the first tangible clue in the mystery—a relatively new virus.

Colony collapse disorder became widespread in America in the winter of 2006-2007，when about a quarter of the nation’s beekeepers were affected，each losing between 30% and 90% of their winged workers.Bees are valued not so much for their honey，which is worth some $200m a year in America，but for their work in pollinating crops.This brings the economy some$15 billion a year，as apiarists move their hives to land producing fruit，vegetables and nuts.

Finding exactly why colonies collapse has been taxing the minds of both federal and university scientists.There have been few bodies on which to conduct autopsies.Those adult bees that have been found dead near an abandoned hive have been riddled with almost every bee disease known to man.Now a report by Diana Cox-Foster of Pennsylvania State University and her colleagues，published in the September 6th issue of Science，points the finger at the Israeli acute paralysis virus.The lurgy in question was，the researchers suggest， imported from Australia.

Because many factors could be acting together to cause bee colonies to collapse， Dr.Cox-Foster and her colleagues decided to examine everything they could find within the empty hives.They collected samples from infected hives and compared them not only with samples from apparently healthy hives but also with an analysis of royal jelly—a bee secretion fed to the larvae—from China，which has not been affected by the mystery disorder.From their samples，the researchers extracted RNA—a chemical that carries and helps to decode genetic information.Their analysis revealed the presence of various bacteria，fungi and viruses that were lurking in the hives and the royal jelly.They then looked to see whether there was anything in the abandoned hives that was not found elsewhere.

What they found was a virus first identified in 2004 in the Middle East.Bees infected with Israeli acute paralysis virus shiver，their bodies become frozen and they die.But the virus itself cannot be the sole cause of colony collapse disorder.For a start，all the hives infected with it were also infested with a second nasty，the Kashmiri bee virus.Yet this virus was also present in many of the apparently healthy hives.Intriguingly，there was also a virus that the researchers were unable to classify.They suspect it may be a new lineage of the Kashmiri bee virus，but it could be something completely novel.This second virus was also found only in the abandoned hives.

The researchers reckon that the reason why so many honey bees are dying is down to a combination of factors that are found only，so far，in America.The Israeli acute paralysis virus may have had such a devastating effect there because of the presence of a parasite called the Varroa mite.This parasite weakens the immune systems of bees，making the consequences of an infection more likely to be fatal.Tellingly，bees in Australia have not been infected by the parasite.

1.When honey bees desert their hives，the other bees will usually____.

A.stay far away from the empty hives because they are useless

B.flee their queen，the young and their food stores away and steal the hives

C.throw apiarists into a panic by plaguing the empty hives

D.plunder the empty hives and take possession of all that is worth anything

2.When the bee colony collapse disorder became rampant in America，____.

A.the workers of the nation’s beekeepers resigned from the beekeeping factory

B.the apiarists moved their hives to land producing fruit，vegetables and nuts

C.the crops could not grow to maturity as before for short of effective pollination

D.each apiarist suffered a loss of$200m to$1b a year as well as most of their workers

3.It has been a headache to find out why bee colonies collapse because of the following reasons EXCEPT____.

A.RNA experiment shows an intricate connection between the dead bees with their Chinese counterparts

B.dead bees near a deserted hive are found to carry too many diseases

C.there were almost no samples for scientists to do research on the dead bees

D.the scientists could not identify exactly which disease was the main factor that had caused the colonies collapse

4.Which one of the following statements is NOT true of the experiment carried out by Dr.Cox-Foster and her colleagues？

A.They collected samples not only from infected hives，but also from healthy hives and royal jelly.

B.They sorted out a chemical that provides relevant information from the genetic perspective.

C.The research points out that an Israeli virus is the main cause of the collapse disorder since the virus was found in the hives and the royal jelly.

D.They found that there were all kinds of viruses in the royal jelly which were also present in the infected hives.

5.According to the researchers，so many honey bees are dying probably because of the following reasons EXCEPT____.

A.the bees were affected with Israeli acute paralysis virus which was fatal to them

B.the hives were infected with a combination of the viruses that led to massive deaths of the bees

C.an unidentified virus which may be a new lineage of the Kashmiri bee virus or a new virus causes the disaster

D.the Varroa mite is believed to worsen the conditions of the infected bees and leave them more vulnerable to deadly disease

Passage 17

The animal dissection requirement of biology classes has been getting under the skin of students for generations，and there have always been some who asked to be excused from the requirement.Now，a growing number of technological alternatives are making it possible for students to swap that scalpel for a computer mouse.There are laws in nearly a dozen states—including California，Florida，New Jersey，and New York—protecting a student’s choice to learn about animal anatomy sans scalpel.Some students choosing to opt out feel we should be kinder to our web-footed friends.Others are just queasy at the thought of rubbery frog bodies and the smell of formaldehyde.

“Dissection is icky.There’s a yuck factor，”admits Brian Shmaefsky，a board member with the National Association of Biology Teachers.“And a teacher has to weigh the benefits with the cost of students being offended to the point that it interferes with learning.”

Virtual blades.So for cases in which a real dissection would be too slimy，it’s time to try some toad tech.While the first computer-based alternatives to dissection emerged in the 1980s，modern frog dissection software can be found at different websites.These software programs use creative clicking，high-powered zoom functions，and video clips to teach anatomy.Froguts software，for example，lets students trace incision lines with a computer mouse and snip through skin with a virtual blade.There are even sound effects like a“slish” for slicing frog flesh，or a“shwoosh”for pinning down skin flaps.（Schools currently pay about$300 for a one-year software license，though some organizations will lend programs out free of charge.）

Earlier this year，a graduate student from Simon Fraser University in Vancouver designed the first-ever haptic（the Greek word for“touch”）frog dissection program，which uses a penlike tool to create a sensation similar to cutting into real flesh.The hand-held device connects to a computer，and students move the device through the air while watching the results of their actions on a computer screen.

With Digital Frog—a popular program that’s had approximately 1，500 frog demo downloads since January and is currently in use in 2，000 schools—students can add or subtract those amphibious organs with a mere mouse click.They can then assess their learning with sporadic frog anatomy quizzes.

“Repetition is helpful.The fact that a student can review sections of a program over and over again is important，”says Martin Stephens，vice president for animal research issues at the Humane Society of the United States.“In dissections，the animal’s organs are all shriveled and discolored.You look for things and can’t find them because body parts have changed drastically since the animal was killed.But on a computer screen，layers can be digitally peeled away.”Other experts think the dissection technology has its limits.Gerry Wheeler，executive director of the National Science Teachers Association，says that artificial simulations don’t give as enriching an experience as the real thing.Still others worry the programs are depriving kids of experiential learning.

1.The word“swap”（Paragraph 1）most probably means____.

A.exchange B.throw away

C.reject D.refuse

2.Some students ask to be excused from the requirement of biology classes because of the following reasons EXCEPT that____.

A.dissection consists of disgusting procedures and unpleasant smells

B.they are entitled to reject dissection requirement given the legal regulation

C.they are offended when fulfilling the requirements of animal dissection

D.they insist that people should treat animals more as friends instead of simply objects

3.Brian Shmaefsky’s statement implies that____.

A.he indeed supports the students’animal protection movement

B.he thinks the animal dissection should be banned

C.he thinks the animal dissection may not be good for students to learn biology effectively

D.he always evaluate the teaching effect by weighing reluctant factors of cost and effect

4.Compared with the real dissection，the dissection on computer has the following advantages EXCEPT____.

A.it has authentic sound effect like a“slish”or“shwoosh”

B.there is a sensation of always dealing with fresh and recognizable organs

C.the process can be repeated so that students can gather better insight of the animal structure

D.students can take quizzes with the software to evaluate the learning effect

5.The author’s attitude towards the toad tech can be said to be____.

A.supportive B.doubtful

C.objective D.biased

Passage 18

We sometimes think humans are uniquely vulnerable to anxiety，but stress seems to affect the immune defenses of lower animals too.In one experiment，for example，behavioral immunologist（免疫学家）Mark Laudenslager，at the University of Denver，gave mild electric shocks to 24 rats.Half the animals could switch off the current by turning a wheel in their enclosure，while the other half could not.The rats in the two groups were paired so that each time one rat turned the wheel it protected both itself and its helpless partner from the shock.Laudenslager found that the immune response was depressed below normal in the helpless rats but not in those that could turn off the electricity.What he has demonstrated，he believes，is that lack of control over an event，not the experience itself，is what weakens the immune system.

Other researchers agree.Jay Weiss，a psychologist at Duke University School of Medicine，has shown that animals who are allowed to control unpleasant stimuli don’t develop sleep disturbances or changes in brain chemistry typical of stressed rats.But if the animals are confronted with situations they have no control over，they later behave passively when faced with experiences they can control.Such findings reinforce psychologists’suspicions that the experience or perception of helplessness is one of the most harmful factors in depression.

One of the most startling examples of how the mind can alter the immune response was discovered by chance.In 1975 psychologist Robert Ader at the University of Rochester School of Medicine conditioned（使形成条件反射）mice to avoid saccharin（糖精）by simultaneously feeding them the sweetener and injecting them with a drug that while suppressing their immune systems caused stomach upsets.Associating the saccharin with the stomach pains，the mice quickly learned to avoid the sweetener.In order to extinguish this dislike for the sweetener，Ader re-exposed the animals to saccharin，this time without the drug，and was astonished to find that those mice that had received the highest amounts of sweetener during their earlier conditioning died.He could only speculate that he had so successfully conditioned the rats that saccharin alone now served to weaken their immune systems enough to kill them.

1.Laudenslager’s experiment showed that the immune system of those rats who could turn off the electricity____.

A.was strengthened B.was not affected

C.was altered D.was weakened

2.Laudenslager has demonstrated that it is the____that weakens the immune system.

A.mild electric shocks B.the saccharin

C.the depressed mind D.the lack of control over an event

3.According to the passage，the experience of helplessness causes rats to____.

A.try to control unpleasant stimuli

B.turn off the electricity

C.behave passively in controllable situations

D.become abnormally suspicious

4.The reason why the mice in Ader’s experiment avoided saccharin was that____.

A.they disliked its taste B.it affected their immune systems

C.it led to stomach pains D.they associated it with stomachaches

5.The passage tells us that the most probable reason for the death of the mice in Ader’s experiment was that____.

A.they had been weakened psychologically by the saccharin

B.the sweetener was poisonous to them

C.their immune systems had been altered by the mind

D.they had taken too much sweetener during earlier conditioning

Passage 19

Although close relationships are often wellsprings of health-enhancing support， accumulating evidence indicates that persistent domestic conflict deals a blow to the body—and especially the heart.In one of the latest studies，researchers found that British adults who were in adverse close relationships were 34 percent more likely to suffer coronary problems，ranging from chest pain to deadly heart attacks，than those who weren’t.Numerous American studies have produced similar findings.Last year， for example，a long-term analysis of more than 1，000 marriages found that strained matrimonies take a clear toll on physical health over time，hitting the elderly the hardest.

Negativity-plagued relationships are toxic in part because of the effects of chronic stress，says Sheldon Cohen，a Carnegie Mellon University psychologist.In addition to damaging the heart，ongoing stress can deplete the immune system—creating openings for colds，cancers，and other maladies—and also lead to depression and risky coping behaviors like excessive drinking.

People who endure persistent interpersonal problems are more at risk than those reeling from an isolated blowup，Cohen says.But spouses aren’t the only potential source of unrelenting trouble.In the recent British study，20 percent of adults identified someone other than a romantic partner as the object of their closest relationship，according to the report in the October 8 issue of Archives of Internal Medicine.

Fortunately，strategies for minimizing feuds within the family are similar to those that can resolve conflicts with in-laws，coworkers，neighbors，and others，says Redford Williams，a behavioral scientist at Duke University.One technique he recommends is this：Before lashing someone with a sharp-tongued comment，step back and evaluate a brewing dispute.Say it’s your turn to host the annual holiday family feast.Frazzled，juggling food prep for 20 people with a maniacal effort to scrub everything clean，you finally feel pleased by your home’s facelift.Then the doorbell rings.In strides your 84-year-old aunt，craning her neck to eyeball the surroundings.“Well you certainly don’t pay much attention to keeping your house tidy，”she barks，flinging her coat over your outstretched arms.“If we did what came naturally，we’d either explode or keep fuming for the rest of the day，”Williams says.Instead，he suggests，ask yourself four questions：Is this situation important？

After years studying the strain hostility and anger place on the heart，he and his wife，also a doctor，have developed a system called Williams LifeSkills.A 2005 study found that when people with heart disease used Williams’s techniques，their anger levels，average blood pressure，and blood pressure elevation when angry all went down；their depression and anxiety diminished；and they reported being more satisfied with family and friends.

Nevertheless，the holidays tend to strap everyone with a little extra stress，so make an effort to be on your best behavior，especially if you’re prone to conflict，says Williams.But if family fighting becomes an annual theme，there might be something wrong.

Not all conflict is bad，according to Harvard University lecturer Tal Ben-Shahar，author of the new book Happier：Learn the Secrets to Daily Joy and Lasting Fulfillment.“Negativity is normal，as long as it’s outweighed by positivity，”he says.“No negativity at all is actually a bad sign”that people may be avoiding serious issues.

1.From the first paragraph，it can be inferred that____.

A.close relationship between matrimonies is a double-edged sword

B.adverse close relationships lead to high risk of coronary problems

C.strained relationship within family will cut short one’s normal span of life

D.numerous studies have proved the devastating effect of close relationship

2.Negative close relationship may lead to the following diseases EXCEPT____.

A.coronary problems B.immune system disorder

C.psychosis D.depression and anxiety

3.By the technique recommended by Redford Williams，the author implies that.

A.one should be reasonable so as to keep good relationship with intimate partners

B.one should divert oneself from the furious state so as to minimize family conflicts

C.it is not so difficult to lessen the conflicts within the family

D.you’d better think the other way when potential conflict is under your nose

4.The strategy for minimizing conflicts in the family suggested by Redford Williams is that____.

A.people should undertake housework on one’s own

B.people should choose a brewing dispute rather than a sharp-tongued comment

C.people should weigh if it is worth of having a feud

D.people should learn to hold their anger when something unpleasant happens

5.Which one of the following statements is TRUE of Tal Ben-Shahar’s opinions on family conflict？

A.Family conflict is necessary for maintaining the positivity in close relationships.

B.Lack of family conflict will make people void of serious issues.

C.Negativity in close relationship can indeed improve the relationship positively.

D.Modest family conflict will do little harm to close relationship.

Passage 20

Often people with deep vein thrombosis do not have any symptoms.In these people， this condition is usually suspected only after a blood clot is discovered in the lung.Once diagnosed with deep vein thrombosis，treatment begins if it is likely that the blood clot will grow or that a piece of the clot might break loose and flow to the lungs.

If you have a blood clot in your upper leg vein，you will usually need to take anticoagulant medication for 3 to 6 months，and possibly longer.After 3 to 6 months，your doctor may recommend that you continue Warfarin on an ongoing basis to prevent deep vein clots from recurring.Typically，if you have a blood clot in the lower deep leg veins，you will need to take anticoagulant medication for 6 to 12 weeks fan monitor the blood clot with ultrasound.

The main goal of treatment is to prevent the blood clot from growing or moving to the lungs.If a blood clot in the deep veins of the leg breaks loose and travels to the lungs，it can cause pulmonary embolism.Pulmonary embolism occurs in 25% of cases of untreated， diagnosed deep leg vein thrombosis.In people who receive treatment for deep vein thrombosis，the rate of pulmonary embolism falls drastically.Blood clots in the lung occur more often in people with deep vein blood clots in the upper rather than the lower leg veins. Only about 20% of blood clots in the veins of the calf will become larger and extend into the upper leg or groin veins.Blood clots that extend into the upper leg veins usually require with anticoagulant medication to prevent pulmonary embolism.

The recurrence rate for deep vein thrombosis varies depending on what caused the blood clot and how it was treated.Recurrence is most common in people who have continuing risk factors such as cancer or inherited blood-clotting problems and in people who have more than one blood clot in the leg.Recurrence is lowest in people who have a short-term risk factor，such as surgery or temporary inactivity.In 30% to 50% of people who have had deep vein thrombosis with symptoms，a condition called post thrombotic syndrome may develop within 8 years.This condition can cause pain，swelling，discoloration， and sores on the leg.

1.Once diagnosed with deep vein thrombosis，the patient will be given the treatment to____.

A.dissolve the existing blood clots

B.break loose the existing blood clots

C.prevent the new clots from forming

D.prevent the existing blood clots from growing and moving to the lungs

2.If a patient is found a clot in his lower deep leg vein，he will have to____.

A.take anticoagulant medication for 3 to 6 months

B.monitor his blood clot with ultrasound with no need for medication

C.take anticoagulant medication for 6 to 12 weeks

D.need continuous use of Warfarin

3.According to Paragraph 3，Pulmonary embolism is most likely to occur when____.

A.blood clots are found in the upper leg veins

B.more than one blood clot is found in the leg

C.blood clots appear in the lower leg veins

D.proper treatment was given to patients with deep vein thrombosis

4.The recurrence rate for deep vein thrombosis may be the lowest among people____.

A.who have had a family history of blood-clotting problems

B.who have been diagnosed with deep vein thrombosis after undergoing the mastectomy due to breast cancers

C.whose deep vein thrombosis are caused by temporary sedentary work

D.who have more than one clot in the leg

5.The author of this passage focuses on the____of deep vein thrombosis.

A.treatment

B.early diagnosis

C.treatment and prevention

D.treatment and prognosis

Passage 21

After 25 years battling the mother of all viruses，have we finally got the measure of HIV？Three developments featured in this issue collectively give grounds for optimism that would have been scarcely believable a year ago in the wake of another failed vaccine and continuing problems supplying drugs to all who need them.

Perhaps the most compelling hope lies in the apparent“cure”of a man with HIV who had also developed leukemia.Doctors treated his leukemia with a bone marrow transplant that also vanquished the virus.Now US Company Sangamo Biosciences is hoping to emulate the effect patients being cured with a single shot of gene therapy，instead of taking antiretroviral drugs for life.

Antiretroviral therapy（ART）is itself another reason for optimism.Researchers at the World Health Organization have calculated that HIV could be effectively eradicated in Africa and other hard-hit places using existing drugs.The trick is to test everyone often，and give those who test positive ART as soon as possible.Because the drugs rapidly reduce circulating levels of the virus to almost zero，it would stop people passing it on through sex. By blocking the cycle of infection in this way，the virus could be virtually eradicated by 2050.

Bankrolling such a long-term program would cost serious money—initially around$3.5 billion a year in South Africa alone，ring to$85 billion in total.Huge as it sounds，however，it is peanuts compared with the estimated$1.9 trillion cost of the Iraq war，or the$700 billion spent in one go propping up the US banking sector.It also looks small beer compared with the costs of carrying on as usual，which the WHO says can only lead to spiraling cases and costs.

The final bit of good news is that the cost of ART could keep on falling.Last Friday，GlaxoSmithKline chairman Andrew Witty said that his company would offer all its medicines to the poorest countries for at least 25 per cent less than the typical price in rich countries.GSK has already been doing this for ART，but the hope is that the company may now offer it cheaper still and that other firms will follow their lead.

No one doubts the devastation caused by AIDS.In 2007，2 million people died and 2.7 million more contracted the virus.Those dismal numbers are not going to turn around soon—and they won’t turn around at all without huge effort and investment.But at least there is renewed belief that，given the time and money，we can finally start riddling the world of this most fearsome of viruses.

1.Which of the following can be most probably perceived beyond the first paragraph？

A.The end of the world. B.A candle of hope.

C.A Nobel Prize. D.A quick fix.

2.According to the passage，the apparent“cure”of the HIV patient who had also developed leukemia would____.

A.make a promising transition from antiretroviral medication to gene therapy

B.facilitate the development of effective vaccines for the infection

C.compel people to draw an analogy between AIDS and leukemia

D.would change the way we look at those with AIDS

3.As another bit of good news，____.

A.HIV will be virtually wiped out first in Africa

B.the cycle of HIV infection can be broken with ART

C.the circulating levels of HIV have been limited to almost zero

D.the existing HIV drugs will be enhanced to be more effective in 25 years

4.The last reason for optimism is that____.

A.governments will invest more in improving ART

B.the cost of antiretroviral therapy is on the decline

C.everybody can afford antiretroviral therapy in the world

D.the financial support of ART is coming to be no problem

5.The whole passage carries a tone of____.

A.idealism B.activism

C.criticism D.optimism

Passage 22

European Union environmental officials have determined that two kinds of genetically modified corn could harm butterflies，affect food chains and disturb life in rivers and streams，and they have proposed a ban on the sale of the seeds，which are made by DuPont Pioneer，Dow Agrosciences and Syngenta.The preliminary decisions are circulating within the European Commission，which has the final say.Some officials there are skeptical of a ban that would upset the powerful biotechnology industry and could exacerbate tensions with important trading partners like the United States.The seeds are not available on the European market for cultivation.

In the decisions，the environment commissioner，Stavros Dimas，contends that the genetically modified corn，or maize could affect certain butterfly species，specifically the monarch，and other beneficial insects.For instance，research this year indicates that larvae of the monarch butterfly exposed to the genetically modified corn“behave differently than other larvae”.In the decision concerning the corn seeds produced by Dow and Pioneer，Mr.Dimas calls“potential damage on the environment irreversible”.In the decision on Syngenta’s corn，he says that“the level of risk generated by the cultivation of this product for the environment is unacceptable”.

A decision by the European Union to bar cultivation of the genetically modified crops would be the first of its kind in the trade bloc，and would intensify the continuing battle over genetically modified corn.Banning the applications for corn crops also would mark a bold new step for European environmental authorities，who are already aggressively pursuing regulations on emissions from cars and aircraft，setting it at odds with the United States and angering industries.

“These products have been grown in the U.S.and other countries for years，”said Stephen Norton，a spokesman for the United States trade representative.“We are not aware of any other case when a product has been rejected after having been reviewed and determined safe by European food safety authorities，”he said.

Barbara Helfferich，a spokeswoman for Mr.Dimas，declined to comment on the specifics of the procedure because commissioners had not yet made a final decision.But she said that the European Union was within its rights to make decisions based on the“precautionary principle”even when scientists had found no definitive evidence proving products can cause harm.She said that the decisions by Mr.Dimas could go before the commission within a few weeks，but she said that no date had been set.In the decisions，Mr.Dimas cited recent research showing that consumption of genetically modified“corn byproducts reduced growth and increased mortality of nontarget stream insects”and that these insects“are important prey for aquatic and riparian predators”and that this could have“unexpected ecosystem-scale consequences”.

Although still preliminary，his decisions could drastically tilt the policy against future approvals of genetically modified crops，said Nathalie Moll，a spokeswoman for Europabio，an industry group with 80 members including Syngenta，Pioneer and Dow.Europabio says that the crops grown using the genetically modified corn are already imported into several European countries，including France and Germany，where they are used to feed animals like cows and chickens.

Rob Gianfranceschi，spokesman at the United States mission to the European Union in Brussels，said it was too early to comment on a decision that had not yet been formalized.But he made clear that the United States remained frustrated with European policies on genetically modified crops.

1.The preliminary decisions are made by____.

A.DuPont Pioneer，Dow Agrosciences and Syngenta

B.European Union environmental officials

C.European Commission

D.Stavros Dimas

2.To the decisions，the European Commission officials’attitudes are____.

A.skeptical B.controversial

C.contradictory D.divergent

3.About the decisions，which one of the following statements is TRUE？

A.The decisions aim to put a ban on the sale of the seeds of genetically modified corn due to political and biological concerns.

B.The decisions are warmly embraced by all EU members but bitterly rejected by their trade partners.

C.The decisions could probably be made even if no definitive evidence proving the products harmful is found.

D.There is high possibility that the decisions would be approved by the European Commission.

4.Mr.Dimas cited many researches on the genetically modified corn in his decisions in order to____.

A.dispel some officials’doubt on his decisions

B.enhance the strength of his decision-making

C.demonstrate the latest achievement of his decisions

D.assure that they can be presented before the commission with solid evidence

5.The word“tilt”（Line 1，Paragraph 6）most probably means____.

A.incline B.affect

C.include D.evoke

Passage 23

Once upon a time，the only ideologically acceptable explanations of mental differences between men and women were cultural.Any biologist who dared to suggest in public that perhaps evolution might work differently on the sexes，and that this might perhaps result in some underlying neurological inequalities，was likely to get tarred and feathered.Today，by contrast，biology tends to be an explanation of first resort in matters sexual.So it is salutary to come across an experiment which shows that a newly discovered difference which fits easily，at first sight，into the biological-determinism camp，actually does not belong there at all.

Writing in Psychological Science，a team led by Ian Spence of the University of Toronto describes a test performed on people’s ability to spot unusual objects that appear in their field of vision.Success at spatial tasks like this often differs between the sexes（men are better at remembering and locating general landmarks；women are better at remembering and locating food），so the researchers were not surprised to discover a discrepancy between the two.The test asked people to identify an“odd man out”object in a briefly displayed field of two dozen otherwise identical objects.Men had a 68% success rate.Women had a 55% success rate.

Had they left it at that，Dr.Spence and his colleagues might have concluded that they had uncovered yet another evolved difference between the sexes，come up with a“Just So”story to explain it in terms of division of labour on the African Savannah，and moved on.However，they did not leave it at that.Instead，they asked some of their volunteers to spend ten hours playing an action-packed，shoot-’em-up video game，called“Medal of Honour：Pacific Assault”.As a control，other volunteers were asked to play a decidedly non-action-packed puzzle game，called“Balance”，for a similar time.Both sets were then asked to do the odd-man-out test again.

Among the Balancers，there was no change in the ability to pick out the unusual.Among those who had played“Medal of Honour”，both sexes improved their performances.That is not surprising，given the different natures of the games.However，the improvement in the women was greater than the improvement in the men—so much so that there was no longer a significant difference between the two.Moreover，that absence of difference was long-lived.When the volunteers were tested again after five months，both the improvement and the lack of difference between the sexes remained.Though it is too early to be sure，it looks likely that the change in spatial acuity—and the abolition of any sex difference in that acuity—induced by playing“Medal of Honour”is permanent.

That has several implications.One is that playing violent computer games can have beneficial effects.Another is that the games might provide a way of rapidly improving spatial ability in people such as drivers and soldiers.And a third is that although genes are important，upbringing matters，too.In this instance，exactly which bit of upbringing remains unclear.Perhaps it has to do with the different games that boys and girls play.But without further research，that suggestion is as much of a“Just So”story as those tales from the savannah.

1.The“odd man out”object in the experiment of Ian Spence refers to____.

A.a weird man B.the different object

C.an ugly guy D.something separated from others

2.In Ian Spence’s experiment，the fact that men had higher success rate of identifying the“odd man out”object proves____.

A.that the biological-determinism is universal because men are better at remembering general landmarks than women

B.the cultural conclusion that women are of no difference with men in terms of judging objects

C.that it is an accepted conclusion that men have higher success rate at spatial tasks than women

D.the biological discovery that men are genetically more intelligent than women

3.The word“control”（Paragraph 3）most probably means____.

A.contrast B.regulation

C.monitor D.manipulation

4.Which one of the following case is NOT true of game players’performances of identifying the“odd man out”object？

A.There was no difference between men and women in identifying the“odd man out”object after playing the violent game.

B.Women exceeds men at picking out the unusual object after playing the violent game.

C.Men were the same as women at picking out the unusual object after playing “Balance”.

D.Women improved more greatly in identifying the“odd man out”object after playing“Medal of Honour”.

5.From the game experiment by Ian Spence，the following conclusion can be drawn that____.

A.violent games should be widely promoted to improve people’s ability of remembering and locating general landmarks

B.the reason that boys have better spatial ability is mainly because they play much more violent games

C.genes in determining the spatial ability can not be changed by acquired practice

D.playing violent games could change people’s congenital ability

Passage 24

Only two countries in the advanced world provide no guarantee for paid leave from work to care for a newborn child.Last spring one of the two，Australia，gave up that dubious distinction by establishing paid family leave starting in 2011.I wasn’t surprised when this didn’t make the news here in the United States—we’re now the only wealthy country without such a policy.

The United States does have one explicit family policy，the Family and Medical Leave Act，passed in 1993.It entitles workers to as much as 12 weeks’unpaid leave for care of a newborn or dealing with a family medical problem.Despite the modesty of the benefit，the Chamber of Commerce and other business groups fought it bitterly，describing it as“government-run personnel management”and a“dangerous precedent”.In fact，every step of the way，as（usually）Democratic leaders have tried to introduce work-family balance measures into the law，business groups have been strongly opposed.

As Yale law professor Anne Alstott argues，justifying parental support depends on defining the family as a social good that，in some sense，society must pay for.In her book No Exit：What Parents Owe Their Children and What Society Owes Parents，she argues that parents are burdened in many ways in their lives：there is“no exit”when it comes to children.“Society expects—and needs—parents to provide their children with continuity of care，meaning the intensive，intimate care that human beings need to develop their intellectual，emotional，and moral capabilities.And society expects—and needs—parents to persist in their role for 18 years，or longer if needed.”

While most parents do this out of love，there are public penalties for not providing care.What parents do，in other words，is of deep concern to the state，for the obvious reason that caring for children is not only morally urgent but essential for the future of society.The state recognizes this in the large body of family laws that govern children’s welfare，yet parents receive little help in meeting the life-changing obligations society imposes.To classify parenting as a personal choice for which there is no collective responsibility is not merely to ignore the social benefits of good parenting；really，it is to steal those benefits because they accrue（不断积累）to the whole of society as today’s children become tomorrow’s productive citizenry（公民）.In fact，by some estimates，the value of parental investments in children，investments of time and money（including lost wages），is equal to 20%-30%of gross domestic product.If these investments generate huge social benefits—as they clearly do—the benefits of providing more social support for the family should be that much clearer.

1.What do we learn about paid family leave from the first paragraph？

A.It came as a surprise when Australia adopted the policy.

B.America is now the only developed country without the policy.

C.Its meaning was clarified when it was established in Australia.

D.It has now become a hot topic in the United States.

2.What has prevented the passing of work-family balance laws in the United States？

A.The lack of a precedent in American history.

B.The existing Family and Medical Leave Act.

C.The opposition from business circles.

D.The incompetence of the Democrats.

3.What is Professor Anne Alstott’s argument for parental support？

A.Good parenting benefits society.

B.The cost of raising children in the US has been growing.

C.The US should keep up with other developed countries.

D.Children need continuous care.

4.What does the author think of America’s large body of family laws governing children’s welfare？

A.They fail to ensure children’s healthy growth.

B.They fail to provide enough support for parents.

C.They impose the care of children on parents.

D.They emphasize parents’legal responsibilities.

5.Why does the author object to classifying parenting as a personal choice？

A.It is basically a social undertaking.

B.It relies largely on social support.

C.It is regarded as a legal obligation.

D.It generates huge social benefits.

Passage 25

There is nothing like the suggestion of a cancer risk to scare a parent，especially one of the over-educated，eco-conscious type.So you can imagine the reaction when a recent USA Today investigation of air quality around the nation’s schools singled out those in the smugly（自鸣得意地）green village of Berkeley，Calif.，as being among the worst in the country.The city’s public high school，as well as a number of daycare centers，preschools，elementary and middle schools，fell in the lowest 10%.Industrial pollution in our town had supposedly turned students into living science experiments breathing in a laboratory’s worth of heavy metals like manganese，chromium and nickel each day.This happens in a city that requires school cafeterias to serve organic meals.Great，I thought，organic lunch，toxic campus.

Since December，when the report came out，the mayor，neighborhood activists（活跃分子）and various parent-teacher associations have engaged in a fierce battle over its validity：over the guilt of the steel-casting factory on the western edge of town，over union jobs versus children’s health and over what，if anything，ought to be done.With all sides presenting their own experts armed with conflicting scientific studies，whom should parents believe？Is there truly a threat here，we asked one another as we dropped off our kids，and if so，how great is it？And how does it compare with the other，seemingly perpetual health scares we confront，like panic over lead in synthetic athletic fields？Rather than just another weird episode in the town that brought you protesting environmentalists，this latest drama is a trial for how today’s parents perceive risk，how we try to keep our kids safe—whether it’s possible to keep them safe—in what feels like an increasingly threatening world.It raises the question of what，in our time，“safe”could even mean.

“There’s no way around the uncertainty，”says Kimberly Thompson，president of Kid Risk，a nonprofit group that studies children’s health.“That means your choices can matter，but it also means you aren’t going to know if they do.”A 2004 report in the journal Pediatrics explained that nervous parents have more to fear from fire，car accidents and drowning than from toxic chemical exposure.To which I say：Well，obviously.But such concrete hazards are beside the point.It’s the dangers parents can’t—and may never—quantify that occur all of sudden.That’s why I’ve rid my cupboard of microwave food packed in bags coated with a potential cancer-causing substance，but although I’ve lived blocks from a major fault line（地质断层）for more than 12 years，I still haven’t bolted our bookcases to the living room wall.

1.What does a recent investigation by USA Today reveal？

A.Heavy metals in lab tests threaten children’s health in Berkeley.

B.Berkeley residents are quite contented with their surroundings.

C.The air quality around Berkeley’s school campuses is poor.

D.Parents in Berkeley are over-sensitive to cancer risks their kids face.

2.What response did USA Today’s report draw？

A.A heated debate. B.Popular support.

C.Widespread panic. D.Strong criticism.

3.How did parents feel in the face of the experts’studies？

A.They felt very much relieved.

B.They were frightened by the evidence.

C.They didn’t know who to believe.

D.They weren’t convinced of the results.

4.What is the view of the 2004 report in the journal Pediatrics？

A.It is important to quantify various concrete hazards.

B.Daily accidents pose a more serious threat to children.

C.Parents should be aware of children’s health hazards.

D.Attention should be paid to toxic chemical exposure.

5.Of the dangers in everyday life，the author thinks that people should have more to fear from____.

A.the uncertain B.the quantifiable

C.an earthquake D.unhealthy food