第四部分 ：閱讀理解(第31～45題，每題3分，共45分)
短文后有5道題，每題后面有4個選項。請仔細閱讀短文并根據(jù)短文回答其后面的問題，從4個選項中選擇1個答案涂在答題卡相應的位置上。下面共有15個句子，每個句子中均有1個詞或短語劃有底橫線，請從每個句子后面所給的4個選項中選擇1個與劃線部分意義最相近的詞或短語。
(31)根據(jù)下面材料，回答題。
Human Heart Can Make New Cells
Solving a longstanding mystery, scientists have found that the human heart continues to
generate new cardiac cells throughout the life span, although the rate of new cell production
slows with age.
The finding, published in the April 3 issue of Science, could open a new path for the
treatment of heart diseases such as heart failure and heart attack, experts say.
"We find that the beating cells in the heart, cardiomyocytes, are renewed," said lead
researcher Dr. Jonas Frisen, a professor of stem cell research at the Karolinska Institute in
Stockholm, Sweden.
"It has previously not been known whether we were limited to the cardiomyocytes we are
born with or if they could be renewed," he said.
The process of renewing these ceils changes over time, Frisen added. In a 20-year-old,
about 1 percent of cardiomyocytes are exchanged each year, but the turnover rate decreases
with age to only 0.45 percent by age 75.
"If we can understand how the generation of new cardiomyocytes is regulated, it may be
potentially possible to develop pharmaceuticals that promote this process to stimulate
regeneration after, for example, a heart attack," Frisen said.
That could lead to treatment that helps restore damaged hearts. "A lot of people suffer from
chronic heart failure," noted co-author Dr.Ratan Bhardwaj, also from the Karolinska
Institute.
"Chronic heart failure arises from heart cells dying," he said.
With this finding, scientists are "opening the door to potential therapies to having ourselves
heal ourselves," Bhardwaj said. "Maybe one could devise a pharmaceutical agent that
would make heart cells make new and more cells to overcome the problem they are facing."
But barriers remain. According to Bhardwaj, scientists do not yet know how to increase
heart cell production to a rate that would replace cells faster than they are dying off,
especially in older patients with heart failure. In addition, the number of new cells the heart
produces was estimated using healthy hearts--whether the rate of cell turnover in diseased
hearts is the same remains unknown.
The human heart stops producing cardiac cells____________.
A: when a person is born
B: when a person becomes old
C: when a person gets sick
D: when a person dies
答案:D
解析:細節(jié)題。題干 ：__________ ，人類的心臟停止產(chǎn)生心臟細胞。
利用題干關鍵詞可以定位到短文的第一段，即科學家們發(fā)現(xiàn)，在人的整個生命過程中，
其心臟不斷產(chǎn)生新的心肌細胞。言外之意，這個過程直到人死了才會停止。
(32) The finding could prove to be helpful to____________.
A: the study of longstanding mysteries
B: the analysis of cardiac cells
C: the prevention of chronic diseases
D: the treatment of heart disease
答案:D
解析:
細節(jié)題。題干 ：這一發(fā)現(xiàn)被證明對__________有益。
利用題干關鍵詞可以定位到短文的第二段，即這一發(fā)現(xiàn)將為心臟病的治療開辟新的途徑
。
(33) The people who're in their mid-70s, only 0.45 percent
ofcardiomyocytes____________.
A: are still functional
B: are replaced each year
C: are lost each year
D: are damaged each year
答案:B
解析:
細節(jié)題。題干 ：70多歲的人群中，只有0.45%的心臟細胞__________。
利用題干關鍵詞可以定位到短文的第四段，即一個人20歲時，
其每年被更替的心肌細胞為1%。隨著年齡的增長，該更替率不斷下降，等到75歲時，
只有0.45%。
(34) Chronic heart failure is associated with____________.
A: the death of heart cells
B: the life span of a person
C: the effects of pharmaceuticals
D: the weight of the patient
答案:A
解析:
細節(jié)題。題干 ：慢性心衰與__________有關。
利用題干關鍵詞可以定位到短文的倒數(shù)第三段，即慢性心衰是由心肌細胞死亡導致的。
(35) It remains unknown whether the rate of cell turnover in diseased hearts____________.
A: changes over time
B: can be monitored
C: is the same as that in healthy hearts
D: is high enough to replace cells faster than they're dying off
答案:C
解析:
細節(jié)題。題干 ：有病心臟的細胞更替率是否__________還未知。
利用題干關鍵詞可以定位到短文的最后一段，
即心臟產(chǎn)生的新細胞的數(shù)量是按照健康心臟計算的，
而有病心臟的細胞更替率是否與健康心臟相同還不得而知。
(36) 根據(jù)下面材料，回答題。
Storms Sink Ships
Rescuers have found the bodies of over 130 people killed in two ferry disasters in
Bangladesh.
The accidents happened during a storm that hit the country on April 21. Hundreds more are
missing or feared dead.
The two ferries sank in different rivers near the capital city of Dhakfi as strong winds and
rain hit the South Asian country.
The government has since banned all ferries and other boats from traveling at night during
the April-May stormy season.
One of the ferries, MV Mitali, was carrying far more people than it was supposed to. About
400 passengers fitted into a space made for just 300, police said. The second ferry carried
about 100 passengers.
"The number of deaths is certain to rise," said an official in charge of the rescue work. "No
one really knows how many people were on board the ferry or how many of them
survived."
Ferries in Bangladesh don't always keep passenger lists, making it difficult to determine the
exact number of people on board.
Besides the ferry accidents, at least 40 people were killed and 400 injured by lightning
strikes,falling houses and trees and the sinking of small boats. Storms are common this time
of year in Bangladesh, as are boating accidents. Ferry disasters take away hundreds of lives
every year in a nation of 130 million people. Officials blame these river accidents on a lack
of safety measures: too many passengers in boats and not enough checks on weather
conditions.
Ferries are a common means of transport in Bangladesh. It is a country covered by about
230 rivers. Some 20,000 ferries use the nation's Waterways every year. And many of them
are dangerously overcrowded.
Since 1977, more than 3,000 people have died in some 260 boating accidents.
How many people have been found dead in the two ferry disasters?
A: Over 130.
B: At least 40.
C: About 400.
D: Over 3,000.
答案:A
解析:
細節(jié)題。題干 ：在兩次渡船失事中已發(fā)現(xiàn)多少人死亡?
利用題干關鍵詞可以定位到第一段第一個句子“
救援人員已經(jīng)找到了在孟加拉國的兩次渡船失事中的130多人的尸體”。當然，
實際的死亡人數(shù)還要高。
(37) The two ferry disasters occurred____________.
A: at noon
B: in the morning
C: at night
D: in the afternoon
答案:C
解析:
推理題。題干 ：這兩次渡船失事發(fā)生在__________。
文章中沒有一個句子直接提供這方面的信息。但是第三段間接地傳遞了這方面的信息 ：
政府此后禁止所有的渡船和其他船只在4月或5月的暴風季節(jié)夜航。
(38) How many passengers was MV Mitali designed to carry?
A: 500.
B: 100.
C: 400.
D: 300.
答案:D
解析: 細節(jié)題。題干 ：渡船MV Mitali
的設計載客量是多少?利用題干關鍵詞可以定位到第四段的第二句 ：把大約400
個旅客裝進了只能容納300個旅客的空間。
(39) Officials attribute boating accident to____________.
A: strong winds
B: bad weather conditions
C: the blockages of waterways
D: the lack of safety measures
答案:D
解析:
細節(jié)題。題干 ：官員們說船只失事的原因是__________。
利用題干關鍵詞可以定位到第三段，即缺乏安全措施。
(40) Which of the following statements is NOT true of the two ferry disasters?
A: They were overcrowded.
B: They sank on April 21.
C: The exact number of deaths could be easily determined.
D: They sank somewhere near Dhaka.
答案:C
解析:
細節(jié)題。題干 ：下面有關這兩次渡船失事的說法哪種是錯的?利用選項關鍵詞進行定位，第五段有這樣一句話 ：沒有人真正知道當時有多少人在船上，也不知道有多少人還活著。第六段是這么說的 ：孟加拉國的渡船不是總能留下乘客的名單的，這使得確認船上確切的人數(shù)很困難。
(41) 根據(jù)下面材料，回答題。
Eat More, Weigh Less, Live Longer
Clever genetic detective work may have found out the reason why a near-starvation diet
prolongs the life of many animals.
Ronald Kahn at Harvard Medical School in Boston, U.S., and his colleagues have been able
to extend the lifespan (壽命) of mice by 18 per cent by blocking the rodent's (嚙齒動物)
increase of fat in specific cells. This suggests that thinness--and not necessarily
diet--promotes long life in"calorie (熱量卡) restricted" animals.
"It's very cool work," says aging researcher Cynthia Kenyon of the University of
California,San Francisco. "These mice eat all they want, lose weight and live longer. It's
like heaven."
Calorie restriction dramatically extends the lifespan of organisms as different as worms and
rodents. Whether this works in humans is still unknown partly because few people are
willing to submit to such a strict diet.
But many researchers hope they will be able to trigger the same effect with a drug once they
understand how less food leads to a longer life. One theory is that eating less reduces the
increase of harmful things that can damage cells. But Kahn's team wondered whether the
animals simply benefit by becoming thin.
To find out, they used biology tricks to disrupt the insulin (胰島素) receptor (受體) gene in
lab mice, but only in their fat cells. "Since insulin is needed to help fat cells store fat, these
animals were protected against becoming fat," explains Kahn.
This slight genetic change in a single tissue had dramatic effects. By three months of
age,Kahn's modified mice had up to 70 per cent less body fat than normal control mice,
despite the fact that they ate 55 per cent more food per gram of body weight.
In addition, their lifespan increased. The average control mouse lived 753 days, while the
thin rodents averaged a lifespan of 887 days. After three years, all the control mice had
died, but one-quarter of the modified rodents were still alive.
"That they get these effects by just manipulating the fat cells is controversial," says Leonard
Guarente of the Massachusetts Institute of Technology, who studies calorie restriction and
aging.
But Guarente says Kahn has yet to prove that the same effect is responsible for increased
lifespan in calorie-restricted animals. "It might be the same effect or there might be two
routes to long life," he points out,."and that would be very interesting."
Ronald Kahn and his colleagues can make mice live longer by__________.
A: offering them less food
B: giving them a balanced diet
C: disrupting the specific genes in their fat cells
D: preventing them growing larger
答案:C
解析: 細節(jié)題。題干 ：Ronald Kahn
和其同事通過__________ 能使老鼠活得更長。
利用題于關鍵詞可以定位到第二段的第一句話以及第六段的第一句話，可知答案為C。
(42) According to the passage, we do not know whether humans will benefit from taking in
fewer calories partly because__________.
A: humans, worms and rodents are different
B: most people are not willing to be put on a strict diet
C: the effect is not known
D: genetic changes in tissues can not be performed on humans
答案:B
解析:
細節(jié)題。題干 ：根據(jù)短文，我們不知道人類是否能受益于攝取較少的熱量，因為
__________。
利用題干關鍵詞可以定位到第四段的最后一句話，可知答案為B。
(43) What does the last sentence in the third paragraph imply?
A: People like to lose weight, but they do not like to eat less.
B: People want to go to heaven, but they do not want to die.
C: Mice will go to heaven if they lose weight.
D: Mice enjoy losing weight.
答案:A
解析:
推理題。題干 ：第三段的最后一句話的含義為__________。根據(jù)第三段最后一句話可知
，這些老鼠隨便想吃什么就吃什么，還能減肥，活得更長，就像在天堂一樣。
這是帶著幽默意味的一句話，暗含的意思是，人們對這樣的老鼠有點“嫉妒”。
人們也想減肥，又不想節(jié)食，但是卻不能像這些老鼠一樣。
(44) The average modified mouse lived__________.
A: 3 years
B: 753 days
C: more than 3 years
D: 887 days
答案:D
解析:
細節(jié)題。題干 ：被改良過的老鼠平均能活__________。
利用題干關鍵詞可以定位到倒數(shù)第三段第二句話，可知答案為D。
(45) What can be inferred from the passage about the route to long life?
A: It remains to be studied.
B: It has already been discovered.
C: Eating more leads to long life.
D: Eating less leads to long life.
答案:A
解析:
推理題。題干 ：關于長壽的路線我們可以得出什么?利用題干關鍵詞可以定位到最后一段Guarente說的話，其中用了兩個might，說明還只是一種不確定的猜測，需進一步研究。