鱼鳃

首页 > 试题列表 > 单题解析

213563. （2022•未央区•高二上期中） A new study discovers that sharks do sleep，and they often sleep with their eyes open.Since some sharks have to swim constantly to keep oxygen-rich water flowing over their gills （鱼鳃），people have long thought that they don't sleep at all.
   Researchers from Australia have now recorded a species of shark sleeping for the first time，finishing the long-standing debate about whether sharks sleep.To see if sharks were in fact asleep，the team analyzed the metabolism（新陈代谢）and pose of seven draughtsboard sharks （猫鲨）over 24 hours.When the sharks were resting for five minutes or longer，their oxygen consumption dropped，which suggested the animals were sleeping.And the researchers also noticed that the sharks changed their posture by lying flat and closer to the ground.
   The sharks sometimes slept with their eyeut as well，though，mostly during the day.At night，they tended to keep their eyes open more often，leading researchers to suspect that the sharks' eye closure might have more to do with light than the sleep state itself. "Not only are sleeping sharks less responsive to their surroundings，but they also have lower metabolic rate，" said Michael Kelly，an ecophysiologist at La Trobe University.
   "Sharks are an important group as they are the oldest living jawed vertebrates（颌类脊椎动物）—a character they share with us，"Michael Kelly said."Sharks have been swimming in the sea for over 400 million years and have evolved very little in that time.Understanding how and why these animals sleep will provide important understanding into the function of sleep and how the animal has evolved over time."
   The team points out that more research will be needed to see if other species sleep like the draughtsboard sharks.Next they plan to continue to analyze the sharks' brain activity while they sleep，to learn more about their waking and resting states.

（1）What is the previous misunderstanding about sharks？
A．They sleep with their eyes closed.
B．They breathe in flowing water.
C．They swim frequently at night.
D．They always stay awake.
（2）What do researchers find about draughtsboard sharks？
A．They need to rest every five minutes in the sea.
B．They consume much less oxygen during the day.
C．They have the same pose when awake and when asleep.
D．They might close their eyes not to sleep but to avoid light.
（3）What does paragraph 4 talk about？
A．The process of the research.
B．The findings ot the research.
C．The significance of the research.
D．The introduction of the researchers.
（4）What does the researchers think of their research in the last paragraph？
A．Insufficient.
B．Unrealistic.
C．Meaningless.
D．Inefficient.

共享时间:2022-11-17 难度:2

纠错

下载

相似

组卷

[考点]

科普知识，说明文，

[答案]

DDCA

[解析]

（1）细节理解题。根据第一段A new study discovers that sharks do sleep，and they often sleep with their eyes open.Since some sharks have to swim constantly to keep oxygen﹣rich water flowing over their gills （鱼鳃），people have long thought that they don't sleep at all.（一项新的研究发现，鲨鱼确实会睡觉，而且它们经常睁着眼睛睡觉。由于一些鲨鱼必须不停地游泳，以保持富含氧气的水流过它们的鳃，人们一直认为它们根本不睡觉。）可知之前关于鲨鱼的误解是他们总是醒着，故选D。
（2）细节理解题。根据第三段中的At night，they tended to keep their eyes open more often，leading researchers to suspect that the sharks' eye closure might have more to do with light than the sleep state itself. （在晚上，它们往往会更频繁地睁开眼睛，这使得研究人员怀疑鲨鱼闭上眼睛可能更多地与光线有关，而不是睡眠状态本身。）可知吃水板鲨闭上眼睛可能不是为了睡觉，而是为了避光。故选D。
（3）段落大意题。根据第四段中的Understanding how and why these animals sleep will provide important understanding into the function of sleep and how the animal has evolved over time.（了解这些动物如何以及为什么睡觉，将为了解睡眠的功能以及动物如何随着时间的推移而进化提供重要的帮助。）可知第四段主要讲的是研究的意义。故选C。
（4）推理判断题。根据最后一段The team points out that more research will be needed to see if other species sleep like the draughtsboard sharks.Next they plan to continue to analyze the sharks' brain activity while they sleep，to learn more about their waking and resting states.（研究小组指出，还需要更多的研究来看看其他物种是否像吃水板鲨那样睡觉。下一步，他们计划继续分析鲨鱼睡觉时的大脑活动，以更多地了解它们醒着和休息时的状态。）可推测研究小组认为他们在最后一段的研究不够充分。故选A。

[点评]

本题考查了"科普知识，说明文，"，属于"必考题"，熟悉题型是解题的关键。

转载声明：

本题解析属于发布者收集录入，如涉及版权请向平台申诉！！版权申诉

相似题 全部同步专题复习模拟真题联考专练月考周考期中期末单元寒假暑假副题

212704. （2024•铁一中学•高二上期中）     Years ago，I bought a blouse.That same day，I considered putting it on，but for no particular reason I decided not to.That weekend，I again considered wearing the blouse，but the occasion didn't seem special enough，so again，I passed it up.Fast forward to today，I have never worn that blouse.
    What happened here？Why do people own so many unused possessions，treating them as though they are too special to use？To find out，I ran an experiment in which participants imagined buying a bottle of wine.We had half of the participants imagine considering opening it one night，but deciding not to.Then when we measured how special the wine seemed and participants' intentions to open it later，we found that those who had imagined holding off on opening it were in fact less likely to intend to open it later.When asked the reason，most assumed they were waiting for a future occasion to open it-a more special occasion.
    Why do people fall into this mental trap？Prior research points to two main reasons.
    First，when options are presented one at a time，rather than all at once，it can be difficult to know when to make a decision.So people often end up"holding out" for an idealized future occasion.Second，regardless of the actual reasons behind their feelings and actions，people often come up with their own explanations after the fact.
    Putting these together is a recipe for what psychologists term""specialness spirals".When you give up using something-for whatever reason-if you believe that you are waiting to use it，the possession will start to feel more special.And as you search for the right occasion day after day，it becomes more tempting to hold out for a future occasion.The less you use it，though，the more special it feels，and the cycle continues.Ultimately，the likelihood of using the possession becomes rarer and rarer.The more this happens，the more stuff you have lying around.
    How can you fight specialness spirals？Try committing in advance to using an item on a specific occasion.When buying a dress，tell yourself you'll wear it this weekend.Or when purchasing a candle，plan to light it that day.This strategy encourages you to actually enjoy your possessions.

（1）What were the participants asked to imagine doing in the experiment？
A.Putting off drinking the wine.
B.Evaluating the quality of the wine.
C.Listing reasons for drinking the wine.
D.Discussing how they would deal with the wine.
（2）What does the underlined word"tempting"in paragraph 5 mean？
A.Particular.
B.Ordinary.
C.Appealing.
D.Uninviting.
（3）What can we learn about specialness spirals？
A.They can mislead people into shopping traps.
B.They can lead to a collection of unused stuff.
C.They result from a pessimistic attitude to the future.
D.They help explain the psychology of delayed rewards.
（4）What is the main purpose of the text？
A.To explain a psychological phenomenon.
B To criticize a wrong consumption concept.
C.To remind people to enjoy their possessions.
D.To encourage people to prepare for a rainy day.

共享时间:2024-11-24 难度:2 相似度:2

解析

纠错

下载

组卷

202729. （2020•西安中学•六模） Facebook lets friends connect．They can give each other updates，share photos and post comments．But that's not all．Facebook might also stress users out．
   In a new study，88 volunteers how much time they spent on Facebook and the types of Facebook posts and comments that they made．In addition，they answered questions about their feelings and state of mind．They also offered saliva．Researchers tested it for cortisol．This chemical is a stress hormone．Levels of it vary throughout the day．
   In this study，people with the most Facebook friends，more than 300，had somewhat higher cortisol levels．Additionally，the more Facebook friends that users had，the more likely they were to feel anxious．On the other hand，youths who gave lots of "likes" and supportive comments on Facebook had lower cortisol levels． "The more social support you give to others，the lower your stress hormone levels will be，" says Lupien．
   "This research decidedly combines the social science approach and the medical science approach on an important question in our social-media age，" says Wenhong Chen，a sociologist at the University of Texas at Austin． "It's ready pleasantly new to see Lupien's team study cortisol levels-along with questionnaire data．"
   One finding from Lupien's work surprised Chen．Teens who felt they got a lot of support from others also had higher cortisol levels．Usually，she says，those feelingould protect people from stress． "There are many potential dangers of social media use among young people，" Chen notes．So，she says，enjoy Facebook，but be aware of the risks．
   Lupien suggests that teen Facebook userare information with and support their friends on the site．They shouldn't just stay silent． "if anyone is more stressed，it's the watchers，not the sharers，" she says．Also，she recommends that people who use social media heavily should find time to take active walks，to run or to do other activities．Cortisol increases a person's energy． "The best way to reduce stress hormones is to use the energy，" she says．

（1）Paragraph 2 shows us the        ．
A．research proposes
B．research methods
C．research contents
D．research results
（2）What should we do if we want to feel less stressed？
A．Share as many nine photos as possible．
B．Give more positive comments to others．
C．Listen to music frequently on social media．
D．Communicate less with others on Facebook．
（3）What is Wenhong Chen's attitude towards Lupien's study？
A．Cautious．
B．Critical．
C．Doubtful．
D．Approving．
（4）What can be learned from Lupien's suggestion？
A．There are many dangers on social media．
B．Getting support from e-friends makes us healthier．
C．Sharers on Facebook live a happier life than watchers．
D．Doing physical exercise helps reduce the levels of cortisol．

共享时间:2020-05-18 难度:2 相似度:2

解析

纠错

下载

组卷

213288. （2023•西工大附中•高一下期中） Some bacteria （细菌）have a superpower that scientists would love to use.These bacteria gain energy from light，just as plants do.Scientists have wanted to use cyanobacteria（蓝藻菌）to make electricity.But in previous research，they didn't survive long on artificial surfaces.Researchers have now moved them to a living surface - a mushroom.Their creation is the first mushroom to make electricity.
   Applied Physicist Simon Jackson and his team turned that mushroom into a mini energy farm.This bionic（生物电子的）mushroom combines 3 D printing，conductive ink and bacteria to generate electricity.Its design could lead to new ways of combining nature with electronics.Like plants，cyanobacteria make their own food from sunlight，releasing electrons（电子）.When enough electrons build up in one place，they can create an electric current.
   The researchers needed to bring a lot of these bacteria together.They decided to use 3 D printing to place them precisely onto a surface.Jackson's team chose mushrooms for that surface.After all，they realized，mushrooms naturally host communities of bacteria and other microbes.Finding test subjects for their tests was easy.Jackson simply went to the grocery store and picked up white button mushrooms.
   Printing on those mushrooms，though，turned out to be a real challenge.3 D printers have been designed to print on flat surfaces，but mushroom caps are curved.The researchers spent months writing computer code to solve the problem.Eventually，they came up with a program to 3 D print their ink onto the curved mushroom tops.
   The researchers printed two "inks" onto their mushrooms.One was a green ink made of cyanobacteria.They used this to make a spiral pattern on the cap.They also，used a black ink made of graphene，which is great at conducting electricity.They printed this ink in a branching pattern across the mushroom top.Then it was time to shine.
   "Cyanobacteria are the real heroes here，" says Jackson.When his team shone light on the mushrooms，the bacteria gave out electrons.Those electrons flowed into the graphene and created an electric current.

（1）What was the problem in previous research？
A．Cyanobacteria didn't produce electrons.
B．Cyanobacteria couldn't get enough light.
C．The researchers chose the wrong bacteria.
D．No suitable home was made for cyanobacteria.
（2）Why were mushrooms finally chosen as test subjects？
A．They are convenient to find.
B．They can produce electric currents.
C．They are where bacteria can naturally grow.
D．They can be easily combined with 3 D printing.
（3）What is the major function of the black ink in this test？
A．To feed bacteria.
B．To deliver electrons.
C．To produce electricity.
D．To reshape mushroom tops.
（4）Which of the following is a suitable title for the text？
A．Who are the real heroes？
B．New application of 3 D printing
C．Nature combined with electrons
D．Bionic mushroom makes electricity

共享时间:2023-05-21 难度:2 相似度:2

解析

纠错

下载

组卷

203543. （2025•铁一中学•高二上期末）      Last winter I enjoyed a brief adventure in Guatemala.Over a period of 12 days，I explored through the jungle to watch the sunrise and danced in the street during the holiday parade.But looking back on that trip，what I remember most vividly is a New Year's Eve in Guatemala City，at a lifeless hotel.Rather than a countdown to midnight，I counted down the hours until my departure.
    Nothing special happened during that night.Rather，the big role this hotel plays in my memories can be explained by a psychological principle called the recency effect."The recency effect helps to account for our tendency to remember the ending part of a sequence of events with far more clarity than the rest，"said Dr.Mary Poffenroth，a biopsychologist.
    She says it arises from our short-term memory's inability to hold on to more than a small amount of information at once.So while there is no magic formula to create lovely travel memories，employing the recency effect can turn a good trip into an unforgettable one.
    Dr.Stephanie，a Neuroscientist，says that while you can strategically set off the recency effect at a trip's end，you may have multiple opportunities to create lasting memories all along the way by breaking it up into smaller chunks.
    Keep in mind that the recency effect can also backfire."Ending an amazing trip with stressful flight delays，lost luggage or feeling unwell might be enough to overshadow the entire experience，resulting in remembering the trip as awful instead of joyful，"Stephanie said.
    To avoid disproportionately（不成比例地） spotlighting the final days，Poffenroth has created a trip.She amplifies（增强） earlier days in a trip to keep her memories well-rounded."I collect little bits that will remind me of that day：a subway ticket，a seashell，a cardboard drink with a pub's logo on it."Then，ae is packing on the last day， "I go through all my little found treasures and spend a few moments recalling each one，"she said."This gives me a sense of closure for that chapter of travel and makes the experience memorable."

（1）How did the author feel about the New Year's Eve in Guatemala City？
A.It was boring.
B.It was eventful.
C.It was relaxing.
D.It was cheerful.
（2）What do we know about the recency effect from paragraph 2？
A.It is based on a psychological principle.
B.It is widely used to create lovely memories.
C.It highlights the final part of a series of events.
D.It makes up for the inability of short-term memory.
（3）What does the underlined word"backfire"mean in paragraph 4？
A.Be avoided to some extent.
B.Be applied extensively.
C.Produce undesirable consequences.
D.Pose unexpected challenges.
（4）According to Poffenroth，which of the following may help travelers have good memories？
A.Share travel experiences.
B.Recall the final days of a journey.
C.Purchase as many souvenirs as possible.
D.Purposely gather reminders of a journey.

共享时间:2025-03-01 难度:2 相似度:2

解析

纠错

下载

组卷

205255. （2021•阎良区•高一下期末） Canadians have a global reputation（名声）for being polite.A survey ranked Canada first out of 50 countries.Most Canadians think that while being polite can be a superficial attitude when people are communicating with friend and strangers，being "kind" to others generally requires a much greater effort and truly knows who you are as a person.
   A national survey made by Environics Research Group for Coca-Cola Canada shows that on average each Canadian haown kindness to others through random （随意的）actions four times in the last four weeks.Examples of their kindness include things such as opening a door for a stranger，offering to carry heavy items or giving up your seat for someone else in a public bus.
   With millions of acts of kindness happening every day，most Canadians surveyed felt kind folks deserved more recognition for their actions.Coca-Cola Canada has decided to praise some very special individuals who make others happy with good acts in their own communities.The goal is to share their stories to help inspire others to give a little kindness too.
   "When it comes to kindness，seeing really is believing，" says Carolyn Harty，Senior Brand Manager of Coca-Cola. "More than half of Canadians are inspired to pay it forward themselves when they see others making a kind gesture.It is these small acts of kindness that make a large difference and inspire people and create happiness. "
   Sixteen-year-old Sheliza Kassam，from Canada，decided on her thirteenth birthday that instead of gifts，she and her family would help feed families in need.Her small action became larger and developed into a non-profit organization that Sheliza now runs to hold birthday parties for children living in shelters who otherwise would not be able to celebrate their special day.
   Another teen Nathan Unrau started out with a one-time school charity project that just couldn't help.With the support of his parents，Lunches with Love has become a non-profit organization that makes and gives away 450 paper bag lunches to the local homeless people every other Saturday.

（1）For what are Canadians famous all around the world？
A．Working hard.
B．Being grateful for others' help.
C．Behaving rudely in public.
D．Having good manners.
（2）What does the national survey mainly tell us？
A．Why Canadianow kindness.
B．What kindness means.
C．How kind Canadians are.
D．When Canadianow politeness.
（3）What's the purpose of Coca-Cola Canada's praising the special individuals？
A．To encourage all the people to spread kindness.
B．To celebrate the great events of kindness.
C．To show the ways of making others happy.
D．To remind people of the importance of kindness.
（4）What did Sheliza Kassam and Nathan Unrau have in common？
A．They were once supported by others.
B．They offer others some food.
C．They enjoyed staying with children.
D．They came from the same organizations.

共享时间:2021-07-05 难度:2 相似度:2

解析

纠错

下载

组卷

213667. （2023•鄠邑区•高一下期中）     Optical（光学的）fiber is a flexible line of glass capable of carrying information over long distances.Scientists Dr.Robert Maurer.Dr.Peter Schultz，and Dr.Donald Keck invented the first low-loss optical fiber in 1970.Inspired by their belief that information could be sent through light，they spent four years experimenting with different kinds of glass until they succeeded.
    Optical fiber was an answer to consumer demand for increased bandwidth （带宽）.Beginning in the 1960s.the telecommunications industry realized that the existing copper wire infrastructure（基础设施）could no longer keep up as communications traffic increased.Optical fiber changed the telecommunications industry greatly because it，unlike copper，offered limitless bandwidth.Because of those qualities，optical fiber has become the backbone of the networks that we use today to send voice，data，and video around the world.
    The first optical fiber was celebrated for having a total attenuation of 17 dB/km.Today，there are optical fibers with attenuation as low as 0.17 dB/km，which translates to signal loss being 100 times better than the first one.As a result，optical fiber is the preferred medium for fast.reliable communications networks.
    Today，optical fiber provides the infrastructure for broadband connectivity all around the world.Optical fiber supports all the communications and interactive technology we use every day.Because of the global fiber network，you have instant access to voice，information，and video through devices such as smartphones，computers，high-definition TV.CPS，and game systems through which you get directions，send email，conduct research.join social networks，shop，and download music，movies，and more.
    As has been the case from the very beginning，one driver that shapes the future of optical fiber is market demand.Optical fiber continues to create new opportunities in how we live，work，and play.Innovations such as Cloud Computing will enable us to partner with technology in a way never before possible.

（1）What drives the scientists to invent the optical fiber？
A．No enough copper.
B．Better understanding of light.
C．Invention of glass.
D．Need for faster information sending.
（2）What does the underlined word "attenuation" in Paragraph 3 mean？
A．Signal.
B．Loss.
C．Power.
D．Metal.
（3）What can we learn about the optical fiber in Paragraph 4？
A．It has limited usage.
B．It needs more devices.
C．It benefits life and technology.
D．It offers better resources.
（4）What is the passage mainly about？
A．The development and advantages of optical fiber.
B．The ways to develop optical fiber.
C．The future of optical fiber.
D．Different opinions about optical fiber.

共享时间:2023-05-15 难度:2 相似度:2

解析

纠错

下载

组卷

202596. （2021•高陵一中•二模） Honeybees can't swim，and when their wings are wet，they can't fly，either.But Chris Roh and other researchers at the California Institute of Technology found that when bees drop into bodies of water，they can use their wings to produce little waves and slide toward land—like surfers（冲浪者） who create and then ride their own waves.
As with many scientific advances - Isaac Newton's apple or Benjamin Franklin's lightning bolt — Dr.Roh's experiment began with a walk.Passing Caltech's Millikan Pond in 2016，he observed a bee on the water's surface producing waves.He wondered how an insect known for flight could push itself

through water.
Dr.Roh and his co-worker，Morteza Gharib，used butterfly nets to collect local Pasadena honeybees and observed their surf-like movements.The researchers used a wire to restrict each bee's bodily movement，allowing close examination of their wings.They found that the bee bends its wings at a 30-degree angle，pulling up water and producing a forward force.Bees get trapped on the surface because water is roughly three times heavier than air.But that weight helps to push the bee forward when its wings move quickly up and down.It's a tough exercise for the bees，which the researchers guess could handle about 10 minutes of the activity.
The researchers said the surf-like movement hasn't been documented in other insects and most semiaquatic（半水生的） insects use their legs for propulsion，which is known as water-walking.It may have evolved in bees，they predicted.
Dr.Roh and Dr.Gharib have imagined many practical applications for bees' surfing.One plan is to use their observations to design robots able to travel across sky and sea."This could be useful for search and rescues，or for getting samples of the surface of the ocean，if you can't send a boat or helicopter，"Dr.Gharib said.
（1）What does the author intend to show by mentioning Newton and Franklin？
A．Roh's admiration for them.
B．Roh's chance discovery about bees.
C．Their outstanding talent for science.
D．Their similar achievements in discovery.
（2）What plays the most vital role in a bee's moving forward on water？
A．The air weight.
B．Its leg extension.
C．The water movement.
D．Its continuous wingbeat.
（3）What does the underlined word "propulsion" in Paragraph 4 mean？
A．Fast flight.
B．Driving force.
C．Pulling speed.
D．Explosive power.
（4）According to the last Paragraph，which of the following isn't the practical applications for bees' surfing？
A．Designing robots with the ability to travel across both sky and sea.
B．Rescuing ships or saving sailors trapped in the ocean.
C．Acquiring knowledge of moving samples of the surface of the ocean.
D．Making helicopters in the shape of bees.
（5）What does the text mainly tell us？
A．Honeybees can surf to safety.
B．Bees help scientists make inventions.
C．Insects can adapt to the environment.
D．Nature is a helpful guide for discovery.

共享时间:2021-03-28 难度:2 相似度:2

解析

纠错

下载

组卷

201865. （2024•西安一中•三模）     Fossils （化石），the preserved remains of ancient life，serve as windows into the Earth's rich history.The formation of the fossils is a wonderful journey that unfolds over vast stretches of time，catching good views of the diversity of life that once lived on our planet.
    The journey often starts with the death of an organism in a specific environment.Whether it's a plant，animal or microscopic organisms，the key factor lies in whether the remains are quickly buried.This initial step is critical to protect the organism from its enemies and environmental factors that could lead to breakdown.
    As the remains are buried，they experience layers of sediment （沉积层）.Over time，more layers gather，pressing the lower sediments.This process，known as sedimentation，plays a crucial role in preserving the remains by creating a protective environment that protects them from being destroyed.
    Mineralization is also a key period in the fossilization process.It involves the infiltration （过滤） of minerals into the organic tissues of the buried remains.Groundwater，rich in minerals moves through these layers.The minerals replace the original organic material，transforming the remains into rock-like forms.
    Sometimes，fossilization goes beyond mineralization to a process called petrification.Petrified fossils occur when the organic material is entirely replaced by minerals，often resulting in a good copy of the original organism.This transformation can preserve complex details，such as the skeletal features of animals.For softer organisms or parts like leaves or feathers，the fossilization process involves pressure.Under the weight of sediments，these delicate structures flatten but leave behind detailed imprints.
    The final step in the journey comes when geological processes expose the fossilized remains.Archaeologists then unearth these treasures，revealing the secrets of Earth's ancient inhabitants.This scientific exploration contributes to our understanding of evolution，biodiversity，and the ever-changing landscapes that have shaped the history of life on our planet.

（1）What is the role of fossils in the modern times？        ?
A．To help protect our environment.
B．To help explore the function of the Earth.
C．To enhance knowing the long history of the universe.
D．To provide an insight into the diverse life forms.
（2）Which of the following is the first step of fossilization？        ?
A．The quick pressure caused by rocks.
B．The quick transformation of the remains.
C．The rapid burial of the remains.
D．The mix of groundwater and minerals.
（3）How can a good copy of organisms form？        ?
A．By fossils petrified when minerals replace the organic material.
B．By groundwater moving through them.
C．By accumulating more pressure on them.
D．By creating a protective environment.
（4）What's the text mainly about？        ?
A．The importance of fossils.
B．The process of fossilization.
C．The evolution of ancient animals.
D．The preservation of the remains.

共享时间:2024-04-05 难度:2 相似度:2

解析

纠错

下载

组卷

213316. （2022•师大附中•高一上期中） Clank，clank，clank，clank.Slowly the train climbs the steep （陡峭的） hill.You should look at this train closely because it is very special.It can reach a speed of 120 kilometers per hour，it can go upside down and sideways，and it can accelerate （加速） as fast as a Ferrari.Look at the passengers.They know about this vehicle and they look nervous.In fact，some even look fearful.That's not surprising，as this is no ordinary train ride；in fact，this train is a roller coaster!
   Roller coasters fly up and down hills，move around corners，twist，turn，and even go upside down.But there's a secret to their twists and turns.On a roller coaster ride，the amount of energy needed to go up a hill or through a loop （圈） is always less than the energy gained by coming down the previous hill.Believe it or not，all of the energy needed for a roller coaster ride is provided in the first drop.
   Roller coasters are designed by special engineers.These engineers need to understand mathematics and，especially，physics.They need to work out exactly how much energy will be generated in the first drop.This energy is called potential energy（势能）.Next，the engineers must figure out how much energy each of the following twists and turns will use.This is called kinetic energy（动能）.It's important work.If the engineers work out wrongly，the roller coaster may run backward and get stuck in the middle of the track!
   Nobody wants the roller coaster to get stuck，but it can happen.On rare occasions，a strong wind or a heavy load of passengers may slow the roller coaster just enough to stop it from climbing the next hill.Some roller coasters actually use this as part of their design.
   As long as people are looking for a thrill （刺激），roller coasters will be there to give it to them.Hiding against the force of gravity provides a great feeling that is hard to beat.For many people，roller coasters are the ultimate thrill ride.

（1）When does a roller coaster get all of the energy it needs？
A．When it goes through a loop.
B．When it moves around corners.
C．When it goes up the second hill.
D．When it falls down the first drop.
（2）Which of the following best describes roller coaster engineers' job？
A．Boring.
B．Well-paid.
C．Demanding.
D．Dangerous.
（3）What does the underlined word "this" in paragraph 4 refer to？
A．The roller coaster's getting stuck.
B．The roller coaster's moving slowly.
C．The roller coaster's climbing steep hills.
D．The roller coaster's carrying heavy passengers.
（4）Which of the following is a suitable title for the text？
A．Gravity can be fun
B．The power of a train
C．What an exciting ride!
D．The world's fastest roller coaster

共享时间:2022-11-28 难度:2 相似度:2

解析

纠错

下载

组卷

204537. （2023•西安市蓝田县城关中学•高二下期末）     The discovery of the Komodo Dragons is one of the most important zoological （动物学的） surprises of the 20th century.Before 1912 it was completely unknown and it was believed that there were no more large lizards （蜥蜴） in the world.Then，in that year，a party of fishermen stopped at an almost completely-unknown small island in a group of islands.The fishermen brought back stories of a huge，prehistoric animal living there.The island's name was Komodo.The largest of these lizards was over ten feet from nose to tail.Komodo dragons have also been discovered on several neighboring islands.
    Are the dragons dangerous to humans？Yes.A Swiss tourist who sat down to have a rest while the other people of his tour group went ahead was attacked and eaten by a dragon.All that was left was a piece of his camera.A number of other people have been killed by dragon attacks over the years.The dragons can eat up to 80 percent of their own weight in a single meal.Their attack way is to wait behind trees，then rush forward and give a single large bite to the person or other animal.Most Komodo dragons prefer wild boar （野猪） or deer as their meals，but they will try to attack and get almost every other animal they can find，including other dragons.The largest dragons weigh around 150 kilos.Though the Komodo dragons can see well，they do most of their hunting based on smell.A dragon can recognize a certain smell from several miles when the wind is right.They will hunt when they have to，and these large lizards are more than happy to get an already dead animal when they come across one.

（1）How was the Komodo dragon discovered？
A．Scientists had been looking for it and found it.
B．It was found by chance by some fishermen.
C．Some fishermen looked for it on an island.
D．It was discovered by some tourists.
（2）Komodo dragons have been found         .
A．only on Komodo
B．on several islands near Komodo Island
C．on many islands in the world
D．on all the islands near Komodo Island
（3）These large lizards are dangerous to people，because         .
A．when people attack them，they will fight back
B．humans are their favourite food
C．they will attack and eat humans if they find them
D．they are much bigger than people
（4）A Komodo dragon will eat all the following EXCEPT         .
A．deer
B．humans
C．trees
D．komodo dragons

共享时间:2023-07-12 难度:2 相似度:2

解析

纠错

下载

组卷

213078. （2023•莲湖区•高二上期中）     In 2018，Russian scientists took a soil sample from deep in the permanently frozen ground in Siberia in Russia.They discovered two tiny round nematodes （线虫） frozen in the sample，which were so small that they could only be seen with a microscope.Testowed the soil had been frozen for about 46，000 years old.When the nematodes were placed in room temperature，they began to move.The nematodes are the oldest living animals ever brought back to life after being frozen.The discovery makes up for the research on how living things can survive in tough conditions.
   Nematodes can live for years if they're frozen.They can enter a special state called cryptobiosis （隐生现象），during which animals reduce their activities and consume very little energy.Before this，the longest nematode had been known to survive through cryptobiosis was about 25 years.Being revived after 46，000 years was a new record for any kind of animal.
   The nematodes were sent off to Germany to be studied further.The researchers found the two nematodes were a new species of nematode that had not yet been discovered.That's not too surprising，since there are so many species of nematodes.They also found the nematodes were able to survive being frozen better if they were dried out a little first.The drying helped them produce a special sugar called trehalose （海藻糖），which helped them survive being frozen.The scientists also studied a nematode species that is common these days.They found that it also uses the sugar to protect itself in cryptobiosis.
   Both of the nematodes were females.Before long，they began to have babies.Some kinds of nematodes，including these，have the ability for a single nematode to have babies all by itself.The two original frozen nematodes have now died.But their babies had babies who had babies，and so on.Most of the nematodes only live a month or two unless they get frozen.

（1）What do we know about the two nematodes in the first paragraph？
A．They were the oldest living animals.
B．They were still alive when warmed up.
C．They were found on the surface of the ground.
D．They were the tiniest creatures ever discovered.
（2）How does cryptobiosis affect nematodes？
A．It slows down the pace of their life.
B．It helps them speed up their drying.
C．It gets their body temperature down.
D．It stops them from consuming energy.
（3）Which of the following is unrelated to the nematodes' survival for years？
A．Cryptobiosis.
B．Trehalose.
C．Their sex.
D．Dry condition.
（4）What can be the best title for the text？
A．Female nematodes live longer than the male ones
B．Nematodes can produce young when they are frozen
C．Nematodes are ranked the fastest producing creatures
D．Short-lived nematodes survived for thousands of years

共享时间:2023-11-10 难度:2 相似度:2

解析

纠错

下载

组卷

204078. （2023•西安中学•高一上期末）     Having a smart phone may not be as smart as you think.They may let you surf the Internet，listen to music and take photos wherever you are...but they also turn you into a workaholic，it seems.
   A study suggests that，by giving you access to emails at all times，the smartphone adds as much as two hours to your working day.Experts found that British people work an additional 460 hours a year on average as they are able to respond to emails on their mobiles.The study shows the average UK working day is between 9 and 10 hours，but 2 more hours is spent responding to or sending work emails，or making work calls.
   Almost one in ten admits spending up to three hours outside their normal working day checking work emails.Some workers say they are on call almost 24 hours a day.Nearly two-thirds say they often check work emails just before they go to bed and as soon as they wake up，while over a third have replied to one in the middle of the night.The average time for first checking emails is between 6：00 a.m and 7：00 a.m，with more than a third checking their first email in the period，and a quarter checking them between 11：00 p.m.and midnight.
   Ghadi Hobeika，marketing director of Pixmania，said： "The ability to access millions of Apps has made smartphone invaluable for many people.However，there are disadvantages.Many companies expect their employees to be on call 24 hours a day，seven days a week，and smartphones mean that people cannot get away from work.The more constantly in touch we become，the more is expected of us in work."

（1）With a smart phone the average UK working day is        .
A．11 to 12 hours
B．9 to 10 hours
C．8 hours
D．2 hours
（2）We can learn from the text that the British people        .
A．prefer to check emails in the morning
B．are crazy about different smartphone
C．work more hours with smartphones
D．shorten their normal working hours
（3）What does the underlined word "invaluable" mean？
A．Useless.
B．Necessary.
C．Expensive.
D．Cheap.
（4）What does Ghadi Hobeika feel about smartphones？
A．They are unimportant for most of the people.
B．They have disadvantages for some companies.
C．They are useful to improve the work ability.
D．They make it impossible for people to rest.

共享时间:2023-02-14 难度:2 相似度:2

解析

纠错

下载

组卷

204166. （2023•周至四中•高二下期末）     Imagine cozying up in your bed after a long day.You scroll through your favorite social media apps for what feels like ten minutes，but then you realize hours have passed.You promise yourself just five more minutes—then it's 3：00 am.You wake up tired the next morning and go to work dizzy but do the same thing again that night.You know you need the rest，but you still stay up and sacrifice sleep to scroll aimlessly on your smartphone.
    You are not alone.This phenomenon is called revenge bedtime procrastination （RBP），which is defined by the Sleep Foundation as "the decision to sacrifice sleep for leisure time that is driven by a daily schedule lacking in free time."In other words，it occurs when people stay up late at night to do things they enjoy，such as scrolling the Internet or watching TV，because they feel they lack the freedom to do these things during the daytime.
    How do you know if you're engaging in RBP？Ask yourself these questions：Do you delay going to sleep because you would rather do other things that you enjoy，such as watching TV or YouTube videos or playing video games？Do you stay up late to spend time with friends or family？Do you miss out on sleep even though you know it's important and that there are consequences to pay for feeling tired？Do you feel deprived of your personal life and free time to simply relax？Does your day mostly seem out of your control？Do you delay getting projects done，exercising or completing chores？
    What puts someone at risk for engaging in RBP？Being a"night owl"can make people more inclined to stay up late.Dealing with significant daytime stress，especially tied to work，is a big risk factor.Working extended hours or having a long commute are other risks，since these leave little or no time for entertainment or relaxation.
    A lack of sleep is tied to many different physical and mental health problems.When revenge bedtime procrastination leads to too little sleep，it can cause negative effects on your well-being，such as：fatigue，reduced motivation and productivity，heightened risk of drowsy driving and accidents，worsened anxiety symptoms，reduced self-regulation，metabolic（新陈代谢） disorders，weight gain，obesity，and even some bacterial infections and viruses.

（1）Why do people develop revenge bedtime procrastination？
A．They want to find excuses for sleeping late.
B．They strive to fulfil what they ought to do.
C．They hope to effectively resist fatigue and obesity.
D．They seek to make up for what they can't do during daytime.
（2）Which of the following is an example of RBP？
A．Eating the tasty chocolate at eight o'clock in the evening.
B．Drinking and chatting with your friends or family at weekends.
C．Delaying sleep time to watch your favourite TV series.
D．Working with colleagues to complete important projects at night.
（3）Which of the following is NOT the cause of an increased risk of RBP？
A．You are a person who enjoys staying up late at night.
B．You can scroll your phone during subway commuting hours.
C．You have to overcome great pressure associated with work.
D．You are continuously asked to work overtime by your boss.
（4）What is the text mainly about？
A．A brief introduction to RBP.
B．Symptoms related to RBP.
C．Negative effects produced by RBP.
D．The risks of engaging in RBP.

共享时间:2023-07-12 难度:2 相似度:2

解析

纠错

下载

组卷

213543. （2022•长安七中•高二上期中） Limiting kids' recreational（消遣） screen time to less than two hours a day，along with enough sleep and physical activity，is associated with improved cognition（认知），according to a study published in The Lancet Child & Adolescent Health．
   The study included about 4，500 US children aged 8 to 11 and measured their habits against the Canadian 24-Hour Movement Guidelines for Children and Youth．It found that 51% of the children got the recommended（建议） nine to eleven hours of uninterrupted sleep per night，37% met the recreational screen time limit of two hours or less per day，while 18% met the physical activity recommendation of at least 60 minutes of accumulated physical activity a day．Only 5% of the children in the study met all three recommendations；30% met none at all．
   The researchers found that as each recommendation was met by a participant，there was a positive association with global cognition，which includes memory，attention，processing speed and language．Those who met all three had the most "superior" global cognition，followed by those meeting the sleep and screen time recommendation and finally the screen time recommendation alone，according to the study．
   Other organizations，such as the American Academy of Pediatrics have guidelines in place to help with the management of children's screen time．The organization suggests putting realistic rules or limits in place for how long your children are on their screens，knowing who they are talking to and what they are doing．The amount of recommended screen time depends on the age of the child．Besides，parentould also make sure to encourage physical activity and have bedroom rules such as creating "tech-free zones"．

（1）Who are the target readers of this passage？
A．Researchers．
B．Teachers．
C．Parents．
D．Children．
（2）What is the main idea of this passage？
A．A study on children's screen time is published．
B．US children fail to meet movement guidelines．
C．Organizations are concerned about children's cognition．
D．Limitation on children's screen time is linked to better cognition．
（3）According to the passage，which of the following might contributes least to cognition？
A．Screen time limit．
B．Sleep hours．
C．Physical activity time．
D．Sleep hours and screen time limit．
（4）Why does the American organization suggest creating "tech-free zones"？
A．To make sure children have enough physical playtime．
B．To make sure children have enough sleep time．
C．To make sure children have recreational time．
D．To protect children against radiation．

共享时间:2022-11-19 难度:2 相似度:2

解析

纠错

下载

组卷

202748. （2020•西安中学•一模） Why elephants rarely get cancer is a mystery that has confused scientists for decades．A study led by researchers at Huntsman Cancer Institute （HCI），at the University of Utah and Arizona State University may have found the answer．
   According to the results，elephants have 38 additional modified copies of a gene that encodes p53，a definite tumor suppressor，as compared to humans，who have only two．Further，elephants may have a more powerful mechanism for killing damaged cells that are at risk for becoming cancerous．In isolated elephant cells，this activity is doubled compared to healthy human cells，and five times that of cells from patients with Li-Fraumeni Syndrome，who have only one working copy of p53 and more than a 90 percent lifetime cancer risk in children and adults．The results suggest extra p53 could explain elephants' increased resistance to cancer．
   "Nature has already figured out how to prevent cancer．It's up to us to learn how different animals overcome the problem so we can adapt those strategies to prevent cancer in people，" says co-senior author Joshua Schiffman，M．D．，pediatric oncologist （儿科肿瘤医生） at Huntsman Cancer Institute，University of Utah School of Medicine．
   But Prof Mel Greaves，from the Institute of Cancer Research in London，says we should focus on why humans have such high levels of cancer．He pointed to the rise of unhealthy，cancer-causing behaviors，such as obesity and sunbathing． "You've never seen an elephant smoke!" he added．
   According to Schiffman，elephants have long been considered a walking problem．Because they have 100 times as many cells as people，they should be 100 times more likely to have a cell slip into a cancerous state and cause the disease over their long life span of 50 to 70 years．And yet analysis of a large database of elephant deaths estimates a cancer death rate of less than 5 percent compared to 11 to 25 percent in people．

（1）Why are elephants less likely to get cancer than humans？
A．Elephants are bigger than humans．
B．Elephants have more p53 genes and mechanism killing damaged cells．
C．Elephants are not as clever as humans in walking．
D．Elephants eat more than humans．
（2）Which of the following can be the equivalent of the underlined word "suppressor"？
A．multiplier
B．complex
C．restrainer
D．coordinator
（3）What's Prof Mel Greaves' attitude towards the discovery？
A．Doubtful．
B．Neutral．
C．Critical．
D．Favorable．
（4）What can we infer from the last paragraph？
A．Elephants have longer life than people．
B．There is no chance that elephants die from cancer．
C．The rate of elephants dying from cancer is increasing．
D．It was thought theoretically that elephants could get cancer more easily．

共享时间:2020-03-15 难度:2 相似度:2

解析

纠错

下载

组卷

dygzyyyn

2022-11-17

高中英语 | 高二上 | 阅读理解

下载量
浏览量
收益额

相关试卷 更多>>

2022-2023学年陕西省西安市未央区高二（上）期中英语试卷

更新:2022-11-17 02:17浏览量:2

微信扫码立即登录

AI助手

普通登录

手机登录

微信扫码立即登录

AI助手