2011年理工類職稱英語教材新增文章

第三十八篇
Longer Lives for Wild Elephants
Most people think of zoos as safe places for animals，where struggles such as difficulty finding food and avoiding predators don’t exist. Without such problems，animals in zoos should live to a ripe old age1.
But that may not be true for2 the largest land animals on Earth. Scientists have known that elephants in zoos often suffer from poor health. They develop diseases，joint problems and behavior changes. Sometimes, they even become infertile，or unable to have babies.
To learn more about how captivity affects elephants，a team of international scientists compared the life spans of female elephants born in zoos with female elephants living outdoors in their native lands. Zoos keep detailed records of all the animals in their care，documenting factors such as birth dates, illnesses, weight and death. These records made it possible for me researchers to analyze 40 years of data on 800 African and Asian elephants in zoos across Europe. The scientists compared the life spans of the zoo-born elephants with the life spans of thousands of female wild elephants in Africa and Asian elephants that work in logging camps3，over approximately the same time period.
The team found that female African elephants born in zoos lived an average of 16.9 years. Their wild counterparts who died of natural causes lived an average of 56 years-more than three times as long. Female Asian elephants followed a similar pattern. In zoos，they lived 18.9 years，while those in the logging camps lived41.7 years.
Scientists don't yet know why wild elephants seem to fare so much better than their zoo-raised counterparts. Georgia Mason，a biologist at the University of Guelph in Canada who led the study，thinks stress and obesity may be to blame4.Zoo elephants don't get the same kind of exercise they would in the wild，and most are very fat. Elephant social lives are also much different in zoos than in the wild，where they live in large herds and family groups.
Another finding from the study showed that Asian elephants born in zoos were more likely to die early than Asian elephants captured in the wild and brought to zoos. Mason suggests stress in the mothers in zoos might cause them to have babies that are less likely to survive.
The study raises some questions about acquiring more elephants to keep in zoos. While some threatened and endangered species living in zoos reproduce successfully and maintain healthy populations，that doesn't appear to be the case with elephants. "Currently，zoos are net consumers of elephants，not net producers," Mason says.
詞匯：
predator n.食肉動物 captivity/ n.監(jiān)禁;束縛
ripe adj.成熟的 fare v.過活，生活
infertile adj.不生育的 obesity n.過度肥胖;肥胖癥
注釋：
1.1ive to a ripe old age：這是一種固定用法，意思是live to an age that is considered to be very old(長壽，高壽)。
2.be true for：或者be true of：對……適用。短文中第二段第一句：But that may not be true for
the largest land animals on Earth.這里，作為主語的that指的是第一段所陳述的內(nèi)容。這個句子要傳達的意思是：動物園對其他動物來說是一個安棲之地，而對大象來說卻不然。
3.logging camps：伐木場。Logging作為名詞，意思是：伐木業(yè)。
4.stress and obesity may be to blame：壓力和肥胖是問題的根源。be to blame：該受責備，應(yīng)承擔責任。
練習(xí)：
1.According to the first two paragraphs，unlike other zoo animals，zoo elephants
A.have difficulty eating food.
B.1ive to a ripe old age.
C.are not afraid of predators.
D.develop health problems.
2.Which of the following about the international scientists' research on the life spans of elephants is NOT true?(See paragraph 3)?
A.They compared zoo elephants with wild elephants.
B.They kept detailed records of all the elephants in their care.
C.They analyzed the records of the elephants kept in zoos.
D.The zoo-born elephants they studied are kept in European zoos.
3.What do the scientist find in their research?
A.Female elephants live longer than male elephants.
B.Female zoo elephants live longer than their wild counterparts.
C.Female zoo elephants die much earlier than their wild counterparts.
D.Elephants in zoos and those in the wild enjoy the same long life spans.
4.What are the possible causes of stress and obesity Zoo-raised elephants generally suffer from?
A.They do not like living in herds.
B.They do not get enough exercise.
C.They do not live with their families.
D.Both B and C.
5.Which of the following does the author suggest in the last paragraph 7?
A.It may not be a wise policy to keep elephants in the zoo.
B. Elephants are no longer an endangered species.
C.Zoo-born elephants should be looked after more carefully.
D.Zoos should keep more animals except elephants.
答案與題解：
1.D 短文的第一段告訴我們，人們通常認為動物園內(nèi)的動物沒有獵食的困難，也不受其他獵食動物的威脅，所以一般壽命較長。但第一段并沒有提及大象。第二段則說，動物園內(nèi)的大象卻不然，它們面臨很多健康問題。所以，除了D以外，其他選項均不符合這兩段內(nèi)容。
2.B 第三段告訴我們，動物園，而不是這些研究人員，保存了所有園內(nèi)動物的詳細相關(guān)信息。所以應(yīng)該選擇B。其他三個選項均能在該段中找到相關(guān)內(nèi)容。
3.C 短文的第四段提供了答案。該段告訴我們，野生的雌性大象的平均壽命是動物園里的雌性大象平均壽命的3倍還多。
4.D 短文的第五段提供了答案。該段第三句的意思是：動物園里的大象不像野生大象那樣活動，因此非常肥胖。他們也不像野生大象那樣過著群居的生活，即live in herds and family groups。
5.A 短文通篇陳述了大象在動物園內(nèi)的生存問題，最后一段是全文的總結(jié)。該段第一句指出，對動物園大象的研究向人們提出了一個問題：是否應(yīng)該將更多的大象關(guān)進動 物園。該段還重復(fù)了第一、第二段的觀點：其他動物在動物園能夠很好地繁衍生息，而大象卻不能。所以，A是正確選擇。B、C、D均沒有在文中被提及 第四十五篇
Some People Do Not Taste Salt Like Others
Low-salt foods may be harder for some people to like than others，according to a study by a Penn State College of Agricultural Sciences1 food scientist. The research indicates that genetic factors influence some of the difference in the levels of salt we like to eat.
Those conclusions are important because recent，well-publicized efforts to reduce the salt content in food2 have left many people struggling to accept fare that simply does not taste as good to them as it does to others3，pointed out John Hayes，assistant professor of food science，who was lead investigator4 on the study.
Diets high in salt can increase the risk of high blood pressure and stroke. That is why public health experts and food companies are working together on ways to help consumers lower salt intake through foods that are enjoyable to eat. This study increases understanding of salt preference and consumption.
The research involved 87 carefully screened participants who sampled salty foods such as soup and chips，on multiple occasions，spread out over weeks5.Test subjects were 45 men and 42 women，reportedly healthy，ranging in age from 20 to 40 years. The sample was composed of individuals who were not actively modifying their dietary intake and did not smoke cigarettes. They rated the intensity of taste on a commonly used scientific scale，ranging from barely detectable to strongest sensation of any kind.
“Most of US like the taste of salt. However，some individuals eat more salt，both because they like the taste of saltiness more，and also because it is needed to block other unpleasant tastes in food. "said Hayes." Supertasters，people who experience tastes more intensely，consume more salt than nontasters do. Snack foods have saltiness as their primary flavor，and at least for these foods，more is better，so the supertasters seem to like them more.”
However，supertasters also need higher levels of salt to block unpleasant bitter tastes in foods such as cheese，Hayes noted. "For example，cheese is a wonderful blend of dairy flavors from fermented milk，but also bitter tastes from ripening that are blocked by salt," he said. "A supertaster finds low-salt cheese unpleasant because the bitterness is too pronouncedo6."
Hayes cited research done more than 75 years ago by a chemist named Fox and a geneticist named Blakeslee，showing that individuals differ in their ability to taste certain chemicals. As a result，Hayes explained，we know that a wide range in taste acuity exists，and this variation is as normal as variations in eye and hair color.
“Some people，called supertasters，describe bitter compounds as being extremely bitter，while others. called nontasters，find these same bitter compounds to be tasteless or only weakly bitter，"he said." Response to bitter compounds is one of many ways to identify biological difterences in food preference because supertasting7 is not limited to bitterness. (476)
詞匯：
publicize v.引起公眾對…的注意;(用廣告)宣傳 ferment v.(使)發(fā)酵
geneticist n.遺傳學(xué)家
dietary adj.飲食的;規(guī)定食物的 acuity n.敏銳;尖銳
注釋：
1.Penn State College of Agricultural Sciences：即Penn State University-College of Agricultural Sciences賓州州立大學(xué)農(nóng)學(xué)院。Penn是Pennsylvania的縮寫，是美國賓夕法尼亞州州名。賓州州立大學(xué)建于1855年，在全國共有24 個分校。在句中，Penn State College of Agricultural Sciences用作定語，修飾food scientist。
2.well-publicized efforts to reduce the salt content in food：大力宣傳減少食物含鹽量的做法
3.1eft many people struggling to accept fare that simply does not taste as good to them as it does to others：使得許多人努力去接受適合其他人而不適合他們口味的食物。fare相當于food。
4.1ead investigator：研發(fā)項目負責人
5.…carefully screened participants who sampled salty foods as soup and chips，on multiple occasion，spread out over weeks：……經(jīng)過仔細篩選的實驗參與者，他們在幾周內(nèi)的不同時間里品嘗了湯和薯條等含鹽食物。
6.too pronounced：此處pronounced為形容詞，意為very noticeable，conspicuous(明顯的，顯著的)。
7.supertasting：超重味感
練習(xí)：
1.In paragraph 2，John Hayes points out that
A.it is good to health to eat food without salt.
B.many people reject low-salt food completely.
C.many people accept low-salt tasteless food reluctantly
D.food with reduced salt tastes better.
2.The fourth paragraph describes briefly
A.how to select subjects and what to do in the research.
B.how to identify supertasters and nontasters.
C.why to limit the number of subjects to 87 persons.
D.why to select more male subjects than female ones.
3.The article argues that supertasters
A.1ike the taste of saltiness to block sweet tastes in food. .
B.1ike snack foods as saltiness is their primary flavor.
C.consume less salt because they don t like intensive tastes.
D.1ike to share salty cheese with nontasters.
4.Which of the following applies to supertasters in terms of bitter taste?
A.They like bitterness in foods as well as saltiness.
B.They like high-salt cheese as it has intense bitter taste.
C.They prefer high-salt cheese，which tastes less bitter.
D.They prefer high-salt cheese as it is good to health.
5.What message do the last two paragraphs carry?
A.Taste acuity is genetically determined.
B.Taste acuity is developed over time after birth.
C.Taste acuity is related to one’s eye and hair color.
D.Taste acuity is still a mysterious subject in science.
答案與題解：
1.C 根據(jù)短文的第二段內(nèi)容，很多人因為食物中的含鹽量降低，所以必須做出很大努力(struggling)去適應(yīng)，而低鹽食物對于他們來說，口味很不好 (fare that simply does not taste…good to them)。選項C有accept reluctantly(勉強接受)表達了這層意思，所以是正確的選擇。A、B、D三個選項均是錯誤的。
2.A第四段介紹了科學(xué)家是如何設(shè)計這項研究的，它包含了研究對象的人數(shù)、性別、人選條件、咸度味感分級表等。選項A概括了這方面的內(nèi)容，所以是答案。而選項B、C、D所述內(nèi)容均不符合該段的意思。
3.B短文的第五段提供了答案。supertaster在這里的意思是：口味重的人，在本文中，nontaster是其反義詞，即，口味清談的人。該段 告訴我們，口味重的人消耗更多的鹽;因為快餐食品的主要味道就是咸味，而且咸度越高，口味越好，所以口味重的人對快餐較為偏愛。選項B表達了上述內(nèi)容，所 以是答案。
4.C短文第六段提供了答案。該段告訴我們，奶酪發(fā)酵會產(chǎn)生苦味，supertasters不喜歡苦味，而高含鹽量可以蓋住奶酪里的苦味，這是他們偏愛高鹽奶酪的原因。所以，只有C是正確選擇。
5.A 文章第七段中，Hayes引用了75年前一位遺傳學(xué)專家的實驗。從這項實驗中，Hayes得出的結(jié)論是，Taste acuity(味覺敏度)上的差異與他們頭發(fā)和眼睛的顏色上的差異是同一類
現(xiàn)象，也就是說，都是與生俱來的。第八段又說，這是一種biological difference(生物差異)，所以A是答案。B說味覺敏度是后天形成的，顯然與作者的結(jié)論相左。C說味覺敏度的差異與頭發(fā)和眼睛的顏色上的差異有 關(guān)，顯然是錯誤的。D的內(nèi)容在最后兩段都沒有提到，所以不會是答案