IT’S never a real problem for us when the weather gets cold. We can put on more clothes, stay next to a fireplace, turn on the air conditioner or simply travel to a warmer city to spend the winter – people have many different ways of coping with the cold.
But things are not as easy for plants. Unlike humans, plants can’t move to escape the cold or generate heat to keep themselves warm. So how do they manage to survive the freezing winter?
It turns out that plants have their own strategies too, said a study published on Dec 22 in the journal Nature.
According to researcher Amy Zanne of George Washington University, US, the cold is a big challenge for plants. Their living tissues can be damaged when they freeze. “It’s like a plant’s equivalent to frostbite (凍瘡),” Zanne told Science Daily. Also, the process of freezing and thawing (解凍) can cause air bubbles to form in the plant’s water transport system. “If enough of these air bubbles come together as water thaws they can block the flow of water from the roots to the leaves and kill the plant,” she explained.
To live through cold weather, plants have developed three traits, according to the study. Some plants, such as oak trees, avoid freezing damage by dropping their leaves before the winter chill sets in – effectively shutting off the flow of water between roots and leaves – and growing new leaves and water transport cells when the warm spring returns.
Other plants, pine trees for example, protect themselves by narrowing their water transport cells, which makes it easier for cells to travel among air bubbles.
The third strategy is also the most extreme – some plants die on the ground in winter and start growing as new plants from seeds when conditions get warmer.
However, the study also found that these smart strategies were developed very slowly – over millions of years of evolution. This leads scientists to worry that plants may not be able to deal with human-caused climate change, which has only started occurring over the past few decades.
Scientists are hoping that this study can help people find possible ways to save plants from the threat of climate change.
小題1:What is the article mainly about?
A．Why plants are not afraid of the winter chill.
B．The ways that plants survive cold weather.
C．Changes in plants’ water transport system in winter.
D．How plants evolve to keep up with climate change.
小題2:According to the article, if a plant freezes in the winter, ______.
A．it produces more living tissues to stay alive
B．its leaves quickly fall out and its roots begin to die
C．lots of air bubbles form in its water transport system
D．its water transport system could be blocked in the spring
小題3:How do oak trees usually survive the cold winters?
A．By dropping their leaves before winter.
B．By narrowing their water transport cells.
C．By widening their water transport cells.
D．By leaving only the seeds alive and growing from the seeds in the spring.
小題4:What are scientists worried about when it comes to plants according to the article?
A．Plants may not be able to adapt to the increasingly cold climate.
B．Human activities might have a great impact on the pace of plants’ evolution.
C．Plants may not be able to evolve fast enough to adapt to human-caused climate change.
D．The strategies plants develop are not good enough to protect them against cold.

小題1:B
小題2:D
小題3:A
小題4:C

試題分析：在寒冷的冬天，人們有各種各樣保暖的方法，但是植物怎么過(guò)冬呢？這篇文章講的是植物在寒冷的天氣生存的方法。
小題1:主旨題：從全篇文章和第二段的句子：But things are not as easy for plants. Unlike humans, plants can’t move to escape the cold or generate heat to keep themselves warm. So how do they manage to survive the freezing winter?可知這篇文章講的是植物在寒冷的天氣生存的方法，選B。
小題2:細(xì)節(jié)題：從第四段的句子;“If enough of these air bubbles come together as water thaws they can block the flow of water from the roots to the leaves and kill the plant,” 可知如果植物在冬天被凍住了，會(huì)影響它們的水運(yùn)輸系統(tǒng)在春天就會(huì)被堵塞，所以選D。
小題3:細(xì)節(jié)題：從第五段的句子：Some plants, such as oak trees, avoid freezing damage by dropping their leaves before the winter chill sets in – effectively shutting off the flow of water between roots and leaves 可知橡樹(shù)是通過(guò)在冬天將樹(shù)葉落下，這樣來(lái)在冬天幸存的，選A。
小題4:細(xì)節(jié)題：根據(jù)文章倒數(shù)第二段的句子：This leads scientists to worry that plants may not be able to deal with human-caused climate change, which has only started occurring over the past few decades.可知科學(xué)家擔(dān)心的是植物可能不能進(jìn)化的那么快來(lái)適應(yīng)人類造成的氣候變化。C
練習(xí)冊(cè)系列答案
相關(guān)習(xí)題

科目：高中英語(yǔ) 來(lái)源：不詳 題型：閱讀理解

Scientists have been puzzled by the phenomenon that migrating birds fly not just in groups all the time, but in "V" formations and they have tried to figure out what benefit birds get from this particular formation. Now, a research group from University of London may have found the answer ― migrating birds fly in a "V" to save energy, according to a study published in the journal Nature.
When a bird flaps(振翅) its wings, it stirs the air around it and causes it to move indifferent directions. Scientist found in the study that the air creates an upward-moving wave at the tips of the wings, which means that if a bird flies around the wingtips of another bird, it can get a boost（抬高） from the rising air and therefore use less energy to stay in the air.
Apart form the "free ride" strategy, scientists were also surprised to observe that migrating birds timed their wing beats and adjusted their positions in a very precise way to maximize the lifting effect while avoiding areas where the air move downward.
"They're able to sense what's going on from the bird in front, where this 'good air' is coming from and now how to position themselves perfectly in it," lead researcher Steven Portugal told BBC.
In fact, the "V" formation has long thought to help birds fly more efficiently(效率搞地). A previous study showed that birds' heart rates went down when they were flying together in a "V" formation. Jet fighters were also found to be able reduce their energy use by up to 18% by staying near the wingtips of other jet fighters. Both of these findings led scientists to suspect that the "V" formation had an efficiency purpose, but until now they still lack proof.
"For scientists, the new study provides an insight into an interesting natural phenomenon. But it could mean even more for aircraft companies — helping them understand how they can imitate that with their plane formations to save fuel, said Portugal."
小題1:What is the author's purpose in writing this article?
A．To explain how birds benefit from migration.
B．To introduce how migrating birds find their way.
C．To tell some applications of migrating birds' "V" formations.
D．To report new findings about migrating birds' "V" formations.
小題2: According to the recent study, when birds migrate        .
A．they don't change their lead birds during the whole journey
B．they fly in "V" formations to protect themselves against enemies
C．they form the shape of a "V" to make best use of the lifting effect
D．the air they stir around makes it hard for the birds behind to fly fast
小題3:What is the significance of the new study according to this article?
A．It might inspire aircraft companies to think of ways to improve efficiency.
B．It has proved that the "V" formation can improve in efficiency in many fields,
C．It has led scientists to discover that birds' heart rates go down when they fly in a "V".
D．It shows that the best formation of jet fighters in battle should be a "V" formation.
小題4: The underlined word "imitate" in the last paragraph most probably means "        ".
A．useB．copyC．changeD．learn

查看答案和解析>>

科目：高中英語(yǔ) 來(lái)源：不詳 題型：閱讀理解

New findings from Queen’s University biologists show that in the plant world, bigger isn’t necessarily better.
“Until now most of the thinking has suggested that to be a good competitor in the forest, you have to be a big plant,” says Queen’s Biology professor Lonnie Aarssen. “But our research shows it’s virtually the other way around.”
Previous studies showed that larger plant species monopolize(壟斷) sunlight, water and other resources, limiting the number of smaller plant species that can exist around them. But the research has proved that this is not generally the case in natural vegetation.
In the Queen’s project, PhD student Laura Keating targeted the largest “host plants” of 16 woody plant species growing in the Okanogan Valley, British Columbia. The research team calculated the number and variety of plants that neighbored each large host plant. They then randomly selected plots without host plants and calculated the plant species there as well. The research showed that the massive trees have no effect on the number of species with which they coexist.
Smaller plants have many advantages over their overbearing neighbors, Professor Aarssen notes. Larger species generate physical space niches under their shelters where smaller species grow well. Smaller plants are much more effective than large trees at using available resources. They also produce seeds at a much younger age and higher rate than their bigger counterparts, and settle down much more quickly—thuscompeting with the newly-born plants of larger species.
小題1: What’s the main idea of the text?
A．Smaller plants may have many advantages over their neighbors.
B．In the plant world, the bigger is better than the smaller one.
C．To be a good competitor in the forest, you have to be a small plant.
D．Queen’s University’s students made a new research.
小題2: The underlined word “this” in Para. 3 refers to the view that _____.
A．large and small plants can grow together in harmony
B．larger plant species limit their smaller neighbors’ growth
C．small plant species have their own advantages
D．large and small plant species can never coexist
小題3:What can we learn according to the text?
A．Larger plant species limit the number of smaller ones around them.
B．Smaller plants can limit the number of plant species around them.
C．Smaller plants produce seeds at a higher rate than their bigger counterparts.
D．Larger trees are more effective than small plants at using available resources.
小題4:Which is the CORRECT order in the Queen’s project?
a. Randomly selected plots without host plants and-calculated the plant species.
b. Calculated the number and variety of plants that neighbored each large host plant.
c. Selected the largest individuals or "host plants" of 16 woody plant species.
A．a(chǎn), b, cB．c, b, a
C．b, c, aD．a(chǎn), c, b

查看答案和解析>>

科目：高中英語(yǔ) 來(lái)源：不詳 題型：閱讀理解

There are many things that go into making a successful school, and success can be measured in many ways. Often, the teachers are praised for a school’s success and blamed for its failure. Yet, in order for a school to be effective, it must be a place where teaching and learning can easily take place, and that requires the hard work of more than just educators. Students must take learning into their own hands and feel as if what they are doing is as important as it actually is. This can only be done with the cooperation of every adult that is involved in the students’ life. Some of these individuals often go unnoticed, yet the role they play in the students’ lives is immeasurable.
Administrative assistants welcome students at the beginning of the day and answer a large number of questions. When an assistant remembers a student’s name or even something special about that student, it communicates to him that he is cared for. The assistant can also give that extra encouragement for a student to make better choices, especially when they are visiting the principal’s office.
Cafeteria workers have a short period of time to interact with students, but can make a big difference as well. Beyond meeting nutritional needs, cafeteria workers may also on occasion meet the emotional needs of the students they serve. Students benefit from positive interaction with adults, and cafeteria workers may give that extra bit of encouragement that a child needs.
Custodians (管理人員) are often underappreciated for all that they give to schools. They have to be knowledgeable about everything from cleaning to fixing the most intricate (復(fù)雜的) tools. They get to school early in the morning before teachers arrive and lock up late at night after the last student has left from the after-school event. They also make sure teachers are equipped with the necessary items and prepare the rooms so that they are ready for learning. A great custodian also gives that kind word or extra smile to that student who needs it most.
小題1:If an assistant remembers a student’s name, the student will feel that       .
A．he is cared for
B．he is special
C．he has done something wrong
D．he has made progress in study
小題2:Which of the following is TRUE about cafeteria workers?
A．It’s enough for them to cook for the students.
B．It’s hard for them to interact with the students.
C．They can also meet the emotional needs of the students.
D．They have the most interaction with students at school.
小題3:We learn from the fourth paragraph that       .
A．custodians play the least important role in a school
B．the work of custodians often goes unnoticed
C．custodians should be more serious with students
D．custodians’ work is always appreciated at school
小題4:How does the author feel about the staff mentioned in the text?
A．Disappointed. B．Appreciative.
C．Dissatisfied. D．Doubtful.

查看答案和解析>>

科目：高中英語(yǔ) 來(lái)源：不詳 題型：閱讀理解

DAVID Beckham. Cristiano  Ronaldo and Rnfacl Nadal while you watch sports and admin* the players’ skills, do you ever notice how handsome the players are?
Yes, sportsmen tend to be handsome. And they haven’t only attracted the interest of the audience even scientists are now studying their good looks.
In a recent study, Erik Postma, a biologist at the University of Zurich in Switzerland, collected the headshots（頭像）of 80 professional athletes from I hr 2012 Tour He France, a bicycle race held in Franco. The race, which covers 3,200 kilometers in 23 days, is often considered to In* one of the hardest endurance（耐力）events, according to The Telegraph.
Postma then asked female participants to score the cyclists’ attractiveness.judging them only based on their facial appearances. So, if a participant recognized any of the cyclists, meaning she knew how good he was at the sport, her score wouldn’t count.
After comparing all the scores with the cyclists’ performances in the 2012 race, Postma was surprised to find that the best riders were rated on average 25 percent more attractive than the worst ones. For example, one of the cyclists, Maxime Monfort , came third in terms of attractiveness and sixth in terms of performance, reported Discovery News.
But where did women get the ability to single out a good rider by simply looking at his face?
According lo Postma, evolution (進(jìn)化) seems to be the answer. In ancient times, women preferred to marry strong men because they would provide good genes for their children. A man with great endurance was also able to cover long distances to hunt for food, which would allow him to better feed the family. “That’s why endurance performance was a key evolutionary factor.” Postma told Discovery News.
As you can see, it’s not that sportsmen ate more attractive themselves, women were just born to think of them that way.
Perhaps surprisingly, when Postma did the same test with male participants, he found that men actually had a quite similar view on which riders were handsome. Even
though most men aren’t aware of it. they inherited (繼承) this ability from their ancient past, when it was necessary to “spot potential competitors” , explained Postma.
小題1:What did Erik Postma ask female participants to do in his study?
A．To help collect the headshots of professional cyclists from the Tour de France.
B．To pick out the cyclists whom they are familiar with or appreciate most.
C．To rate the cyclists’ attractiveness according to facial appearance.
D．To predict the cyclists ’ performances based on facial appearance.
小題2:What did Postma discover from his study?
A．The more attractive a cyclist was, the better he performed in the race.
B．Generally, a cyclist’s endurance had nothing to do with his attractiveness.
C．Attractive cyclists proved to have less endurance than those who were less attractive.
D．Those who performed best in the games were considered more attractive than those who performed worst.
小題3:What can we conclude from the last three paragraphs?
A．Women and men hold quite different views on male attractiveness.
B．Men with good looks tend to lie less popular than men with great endurance.
C．A man with great endurance appealed to women in ancient times and this remains the same today.
D．Most men don* t have the same ability as women to single out a good sportsman by simply looking at his face.

查看答案和解析>>

科目：高中英語(yǔ) 來(lái)源：不詳 題型：閱讀理解

A blind baby is doubly handicapped. Not only is it unable to see, but because it cannot receive the visual stimulus（刺激）from its environment that a sighted child does, it is likely to be slow in intellectual development. Now the ten-month old son of Dr. and Mrs. Dennis Daughters is the subject of an unusual psychological experiment designed to prevent a lag（滯后）in the learning process. With the aid of a sonar-type electronic that he wears on his head, infant(嬰兒) Dennis is learning to identify the people and objects in the world around him by means of echoes(回聲).
The device is an improvement of the “Sonicguide”, an instrument produced by Telesensory Systems, Inc., of Palo Alto, Calif, and used by blind adults in addition to a smart or guide dog. As adapted for Dennis, it consists of a battery-powered system about the size of a half dollar that is on a headgear. A transmitter sends out an ultrasonic(超聲的) pulse that creates an 80 degree cone of sound at 6 feet. Echoes from objects within the cone are perceived (felt) as sounds that vary in pitch(音調(diào)) and volume(音量) with the size and distance of the object.
The closer an object is, the lower the pitch, and the larger the object, the louder the signal. Hard surfaces produce a sharp ping, while soft ones send back signals with a slightly fuzzy quality. An object slightly to the right of Denny’s sends back a louder sound to his right ear than to the left. Thus , by simply moving his head right and left and up and down, he can not only locate an object but also get some notion of its shape and size, thanks to the varying qualities of sounds reaching his ears as the cone of ultrasound(超聲波) passes its edges. Dennis likes to use the device to play a kind of peek-a-boo with his mother. Standing on her knee and facing her directly, he receives a strong signal in both ears. By turning his head away, he makes her seem to disappear. “From the first time he wore it,” says Mrs. Daughters, “it was like a light going on in his head.”
What remains to be determined is how well the device will help Dennis cope with his surroundings as he begins to walk and venture further into his environment.
Meanwhile, Telesensory, Inc, is working on the development of sonar(聲納) device with somewhat the same sensitivity as Dennis’s for use by school-age children.
小題1:Dr. and Mrs. Daughters’ research is directed to ________.
A．helping the blind to see and learn as well as others
B．benefiting the learning process of blind children
C．solving blind children’s psychological problems
D．finding out how children develop intellectually
小題2:Infant Dennis becomes the subject of the experiment most probably because ________.
A．he already lags behind the sighted children
B．he leads a life as normal as any other children
C．he is at the early stage of the learning process
D．he has the aid of a sonar-type electronic device
小題3:What can we learn about infant Dennis’ device?
A．Its first design was designed for blind adults.
B．Its battery is as small as a half-dollar coin.
C．It is functionally similar to a sane and guide dog.
D．It has been improved by Telesensory Systems, Inc.
小題4:In the third paragraph, “its edges” refers to ___________ .
A．the edge of an object
B．the edge of the device
C．the boundary of Dennis’ movement
D．the boundary of the sound pitch.

查看答案和解析>>

科目：高中英語(yǔ) 來(lái)源：不詳 題型：閱讀理解

Schooling Matters
March 25, 2014  Chengdu  Michelle Obama
You see, the truth is that I grew up like many of you. My mom, my dad, my brother and I, we lived in a tiny apartment in Chicago, which is one of the largest cities in America. My father worked at the local water plant…
While we certainly weren’t rich, my parents had big dreams for me and my brother. They had only a high school education themselves, but they were determined to send us both to universities.
So they poured all of their love and all of their hope into us, and they worked hard. They saved every penny. And I know that wasn’t easy for them, especially for my father. You see, my father had serious illness called multiple sclerosis(多發(fā)性硬化癥). And as he got sicker, it got harder for him to walk, and it took him longer to get dressed in the morning.
But no matter how tired he felt, no matter how much pain he was in, my father hardly ever missed a day of work, because he was determined to give me and my brother a better life. And every day, like so many of you, I felt the weight of my parents’ sacrifices on my shoulders. Every day, I wanted to make them proud.
So, while most American kids attend public schools near their homes, when it was time for me to attend high school, I took an exam and got into a special public high school where I could get a better education. But the school was very far from my home, so I had to get up early every morning and ride a bus for an hour, sometimes an hour and a half if the weather was bad. And every afternoon, I’d ride that same bus back home and then immediately start my homework, often studying late into the night – and sometimes I would wake up at 4:30 or 5:00 in the morning to study even more.
And it wasn’t easy. But whenever I got tired or discouraged, I would just think about how hard my parents were working for me. And I would remember something my mother always told me – she said, “A good education is something that no one can take away from you.”
小題1:The passage can be sorted as a        ．
A．self-introductionB．short storyC．news reportD．speech draft (草稿)
小題2:Which of the following is TRUE about Michelle Obama and her family?
A．Her parents were poor but had good educational backgrounds.
B．She attended a public high school near her home.
C．Her father suffered a serious disease and became disabled.
D．She was aware of her parents’ sacrifices and expectations.
小題3:Which of the following words best describes Michelle’s father?
A．Optimistic.B．Humorous.C．Strong-mindedD．Generous
小題4:What does Michelle mainly want to tell readers in this excerpt?
A．We should work hard and get good educations.
B．Our parents always have high expectations for us.
C．She is an ordinary person from an ordinary family.
D．The road to the US First Lady is not easy.

查看答案和解析>>

科目：高中英語(yǔ) 來(lái)源：不詳 題型：閱讀理解

Researchers in the psychology department at the University of California at Los Angeles (UCLA) have discovered a major difference in the way men and women respond to stress. This difference may explain why men are more likely to suffer from stress-related disorders.
Until now, psychological research has maintained that both men and women have the same "fight-or-flight" reaction to stress. In other words, individuals either react with aggressive behavior, such as verbal or physical conflict ("fight"), or they react by withdrawing from the stressful situation ("flight"). However, the UCLA research team found that men and women have quite different biological and behavioral responses to stress. While men often react to stress in the fight-or-flight response, women often have another kind of reaction which could be called "tend and befriend." That is, they often react to stressful conditions by protecting and nurturing their young ("tend"), and by looking for social contact and support from others - especially other females ('befriend").
Scientists have long known that in the fight-or- flight reaction to stress, an important role is played by certain hormones(激素) released by the body. The UCLA research team suggests that the female tend-or-befriend response is also based on a hormone. This hormone, called oxytocin, has been studied in the context of childbirth, but now it is being studied for its role in the response of both men and women to stress. The principal investigator, Dr. Shelley E. Taylor, explained that "animals and people with high levels of oxytocin are calmer, more relaxed, more  social, and less anxious." While men also secrete(分泌）oxytocin, its effects are reduced by male hormones.
In terms of everyday behavior, the UCLA study found that women are far more likely than men to seek social contact when they are feeling stressed. They may phone relatives or friends, or ask directions if they are lost.
The study also showed how fathers and mothers responded differently when they came home to their family after a stressful day at work. The typical father wanted to be left alone to enjoy some peace and quiet. For a typical mother, coping with a bad day at work meant focusing her attention on her children and their needs.
The differences in responding to stress may explain the fact that women have lower frequency of stress-related disorders such as high blood pressure or aggressive behavior. The tend-and-befriend regulatory(調(diào)節(jié)的) system may protect women against stress, and this may explain why women on average live longer than men.
小題1:The UCLA study shows that in response to stress, men are more likely than women to _____ .
A．turn to friends for helpB．solve a conflict calmly
C．find an escape from realityD．seek comfort from children
小題2:Which of the following is true about oxytocin according to the passage?
A．Men have the same level of oxytocin as women do.
B．Oxytocin used to be studied in both men and women.
C．Both animals and people have high levels of oxytocin.
D．Oxytocin has more of an effect on women than on men.
小題3:What can be learned from the passage?
A．Male hormones help build up the body's resistance to stress.
B．In a family a mother cares more about children than a father does.
C．Biological differences lead to different behavioral responses to stress.
D．The UCLA study was designed to confirm previous research findings.
小題4:Which of the following might be the best title of the passage?
A．How men and women get over stress
B．How men and women suffer from stress
C．How researchers overcome stress problems
D．How researchers handle stress-related disorders

查看答案和解析>>

科目：高中英語(yǔ) 來(lái)源：不詳 題型：閱讀理解

How the Grand Canyon (大峽谷) was created remains one of the geology’s greatest mysteries. Some evidence suggests that the process was a gradual one in which the Colorado River (which runs through the canyon) slowly cut deeper and deeper into the ground over millions of years. But volcanic rock samples taken from the canyon now suggest that the canyon was down-cut instead.
Down-cutting is when a flood of water rushes over a landscape (地形) with enough force to cut deeply into the ground and leaves behind a canyon. Such a flood is usually released when a natural or man-made dam (堤壩) bursts.
Robert Webb, a research geologist, says natural dams seem to have formed and broken across the Colorado River several times during the last million years. The dams were built when lava(熔巖) from the eruptions of nearby volcanoes flowed into the river. The lava hardened into hard rocks and blocked the river, causing it to back up and form a lake. Each time the lake grew so huge that it broke the rock dam, releasing a flash flood that furthered the down-cutting process and deepened the canyon.
Down-cutting is not just an earthly event. Satellite photos sent back from Mars suggest that the process has happened there, too, say many other researchers.
The photos, taken by the Mars Global Surveyor, indicate that an enormous lake existed on Mars 3.5 billion years ago. The lake spilled into a large nearby hole. One edge of the hole broke, releasing a flash flood that quickly carved out a grand canyon.
The existence of down-cutting on Mars is just one more piece of evidence that the cold, dry planet was once warm and wet.
小題1:In the past, deep canyons were believed to have formed _______.
A．a(chǎn)s a result of a sudden break of volcanoes
B．due to river flows over millions of years
C．owing to the burst of artificial dams
D．thanks to our ancestors’ creative work
小題2:According to the passage, which of the following statements is TURE?
A．Several volcanoes broke out on Mars directly creating grand canyons.
B．Several great lakes existed on the upper parts of the Colorado River.
C．People built high dams on the upper parts of the Colorado River.
D．The Colorado River crossed the Grand Canyon to form down-cutting.
小題3:From the last three paragraphs we learn that _______.
A．there are great lakes on Mars
B．there are active volcanoes on Mars
C．there might be cities on Mars
D．there might be life on Mars
小題4:The passage can be titled as _______.
A．Lakes on Earth and Mars
B．The Cause of Lake Formation
C．The Force of Dam Breaking
D．Canyons—Results of Flood Cutting

查看答案和解析>>

同步練習(xí)冊(cè)答案