2021届高考英语大一轮复习课时作业41Unit21HumanBiology含解析北师大版

2021版高考英语大一轮复习第1部分模块考点复习Unit21HumanBiology课时规范训练北师大版选修720210706228Part 1 阅读完形组合准度练(建议用时40′)Ⅰ.阅读明白得(共8小题；每小题2分，满分16分)A(2021·江西九校联考)Sleeping in a room with too much lighthas been linked to an increased risk of piling on the pounds，a study shows.A team at the Institute of Cancer Research inLondon found women had larger waistlines if their bedroom was“light enough to see across” at night.However， they caution there is not enough evidence to advise people to buy thicker curtains or turn off lights.The women were asked to rate the amount of light in their bedrooms at night as：Light enough to read.Light enough to see across the room，but not read.Light enough to see your hand in front of you，but not across the room.Too dark to see your hand or you wear a mask.Prof.Anthony Swerdlow told the BBC：“In this very large group of people there is an association between reported light exposure at night and overweight and obesity.But there is not sufficient evidence to know if making your room darker would make any difference to your weight.There might be other explanations for the association，but the findings are intriguing enough to guarantee further scientific investigation.”The light is disrupting the body clock，which stems from our evolutionary past when we were active when it was light in the day and resting when it was dark at night.Light alters mood，physical strength and even the way we process food in a 24­hour cycle.Artificial light is known to disrupt the body clock by delaying the production of the sleep hormone melatonin.Prof.Derk­Jan Dijk said there would be no harm in trying to make bedrooms darker.He told the BBC：“People in general are not aware of the light present in their bedroom.I think people should assess their bedroom and see how easy it wouldb e to make it darker.” Street lights，some alarm clocks and standby lights on electrical equipment such as televisions could light a room，he said.“Overall this study points to the importance of darkness，” he concluded.1．The passage mainly tells us ．A．bright bedrooms link to obesityB．dark bedrooms link to obesityC．people should turn off lightsD．people should buy thicker curtains2．What does the underlined word “disrupt” (Paragraph 4) mean?A．Stop. B．Disturb.C．Improve. D．Recover.3．What might Paragraph 4 be used for?A．One possible explanation on disrupting body clock.B．One possible explanation on disrupting mood.C．One possible explanation on disrupting physical strength.D．One possible explanation on artificial light.4．What's Prof.Derk­Jan Dijk's attitude towards the dark room?A．Unclear. B．Doubtful.C．Negative. D．Favorable.【语篇解读】本文是一篇说明文。

高中英语一轮复习 Part I Unit 21 Human biology作业北师大版Ⅰ.完形填空My daughter's car accident last week left me deeply shaken. Audrey escaped with a collarbone (锁骨) __1__，but for days after that I couldn't __2__ my head the thought of how easily I could have lost her. It is a hard truth of parenthood that the more you love, the __3__ you have to lose. The more a child grows, the less __4__ you have over their life. You can not __5__ their hands as they cross the street, __6__ keep them from heading out on a highway because the rain might turn to __7__，as it did that day last week, in New Hampshire, with my __8__ daughter behind the wheel.I remembered that I let her, for the first time, __9__ alone down our dirty road for a quarter mile's __10__ through what were mostly woods, to visit neighbors who just moved in with a daughter of her age. I dressed her up warmly for the trip and gave her a plastic bag filled with peanuts (花生) to __11__along the way. I stood at the window, __12__ her stepping down the driveway. Then she __13__ the peanuts and they scattered (撒落) in all directions; she __14__ to pick them up with her gloves on, which made the job __15__. Then a strong wind came. She gathered up the peanuts that the wind hadn't __16__ away, set out again, and dropped the bag again. She bent down a second time, picking up peanuts one by one. I thought of how __17__ I'd been with her, just __18__ she left. How I'd __19__ that she was taking too long putting on her boots. The way I'd brushed her hair was so __20__ that she cried out once.I wanted, then, to run out and put my arms around her, take her hand and waded with her the rest of the way. But what I did was just stand there.1．A.had B．good C．broken D．hard【答案与解析】C从事故中幸存下来，付出的代价是“断了”锁骨。

课时作业(二十一)[选修模块7Unit 21 Human Biology][限时：40分钟]Ⅰ.单项填空1．Turn the TV down, please. I have little________ for noise.A．tolerance B．resistanceC．dependence D．persistence2．—What made her so upset?—________ .A．Lost her bikeB．Losing her bikeC．She lost her bikeD．Because of losing her bike3．Do you agree or________ the plan? You have a say about this.A．oppose B．refuse C．object D．demand4．He didn't make________clear when and where the meeting would be held.A．these B．this C．it D．that5．As time went on, those unpleasant events were gradually________from his memory.A．wiped out B．stood outC．cleaned out D．put out6．If we________ other people's love and trust in us, we will be cast aside by others one day.A．hold B．take C．abuse D．has7．Every classroom in this modern school is________ with a new TV set.A．equipped B．prepared C．fixed D．placed8．The passengers were robbed________all their money in broad daylight.A．of B．off C．from D．away9．In recent years travel companies have succeeded in selling us the idea that the further we go，________.A．our holiday will be betterB．our holiday will be the betterC．the better our holiday will beD．the better our holiday be10．________ thousands of people outside; it was too noisy.A．There seemed to beB．There seemed to haveC．It seemed to beD．It seemed to haveⅡ.完形填空Jerry is the kind of man you love to hate. He is always in a(n)__11__mood (心态) and always has something__12__to say. In his opinion, the bottom line is your choice__13__you live a life.One morning, he did something you are never__14__to do in the restaurant business: he left the back door open and was__15__up at gunpoint by three armed robbers. While trying to open the__16__，with his hand shaking from__17__，he input the wrong code. The robbers beat him and even__18__him. Luckily, Jerry was found__19__quickly after the robbers had fled and he was rushed to the local first aid center. After 18 hours of operation and weeks of good care, he was out of hospital with fragments (碎片) of the bullets still in his body.Jerry told me what happened after he was sent to hospital. He said the doctors were__20__. They kept telling him he was going to be fine and__21__him into the emergency room. But when he saw the__22__on the faces of the doctors and nurses, he got really__23__. In their eyes, he__24__，“He's dying.” He knew he needed to take__25__. There was a big nurse shouting questions at him. She asked if he was allergic (过敏的) to anything, and the doctors and nurses stopped working as they waited for his reply. Jerry__26__for a while and then he decided to live. He took a deep breath and said, “Yes. __27__！”Over their laughter, Jerry told them to operate on him__28__he wouldn't die.Jerry lived, thanks to the skill of his doctors, but also because of his amazing__29__. I learnt from him that every day we have the choice to live fully. Attitude, __30__ , is everything.11．A.exciting B．good C．usual D．balanced12．A.positive B．funny C．new D．different13．A.how B．where C．whether D．why14．A.advised B．imagined C．asked D．supposed15．A.pulled B．put C．held D．done16．A.box B．safe C．counter D．door17．A.nervousness B．worryC．unwillingness D．pressure18．A.knocked B．killed C．knifed D．shot19．A.probably B．relativelyC．merely D．reasonably20．A.excited B．organizedC．hard-working D．great21．A.rolled B．carried C．wheeled D．forced22．A.surprise B．expressionsC．feeling D．puzzles23．A.scared B．embarrassedC．disappointed D．annoyed24．A.knew B．found C．meant D．read25．A.notice B．order C．breath D．action26．A.thought B．wondered C．judged D．stopped27．A.Medicine B．Operation C．Bullets D．Fragments28．A.unless B．even if C．as if D．before29．A.reply B．attitudeC．opinion D．determination30．A.to be honest B．in that caseC．after all D．strictly speakingⅢ.阅读理解AThe poor are very wonderful people. One evening we went out and we picked up four people from the street. And one of them was in a most terrible condition－and I told the sisters: You take care of the other three. I take care of this one who looks worse. So I did for her all that my love can do. I put her in bed, and there was such a beautiful smile on her face. She took hold of my hand as she said just the words “Thank you” and she died.I could not help but examine my conscience before her and I asked what I would say if I was in her place. And my answer was very simple. I would have tried to draw a little attention to myself. I would have said I am hungry, I am dying, I am cold, I am in pain, or something, but she gave me much more－she gave me her grateful love. And she died with a smile on her face. So did that man whom we picked up from the drain, half eaten with worms, and we brought him to the home. “I have lived like an animal in the street, but I am going to die like an angel, loved and cared for”，he said at the end. And it was so wonderful to see the greatness of that man who could speak like that, who could die like that without blaming anybody, without cursing anybody, without comparing anything. Like an angel－this is the greatness of our people. And that is why we believe what Jesus has said: I was hungry, I was naked, I was homeless, I was unwanted, unloved, uncared for, and you did it to me.And with this prize that I received as a Prize of Peace, I am going to try to make the home formany people who have no home. Because I believe that love begins at home and if we can create a home for the poor I think that more and more love will spread. And we will be able through this understanding love to bring peace, the good news to the poor, the poor in our own family first, in our country and in the world. When I pick up a person from the street, hungry and I give him a plate of rice or a piece of bread, I have satisfied. I have removed that hunger. But to a person who is shut out, who feels unwanted, unloved, terrified, who has been thrown out from society, that poverty is so full of hurt and so unbearable… And so let us always meet each other with a smile, for the smile is the beginning of love, and once we begin to love each other naturally we want to do something.31. What can be learned from the second paragraph?A．The woman should have paid more attention to herself.B. The man couldn't blame anyone.C. The author is religious.D. The man died in the street.32．The purpose of this passage is ________.A．to appeal for more donation for the poorB. to call on the public to love each otherC. to tell the readers the poor are wonderfulD．to express how moved the author is to receive the prize33．Which of the following can NOT be inferred from the passage?A．The author has few supporters.B. The author was somewhat surprised at what the man said.C. The author is delighted to help others in trouble.D. The author may agree to solve social problems in soft ways.34. What's the best title of this passage?A．Have Sympathy for the PoorB. The Poor are WonderfulC. Smile and LoveD. Relieve PovertyBInformation has always been at the center of human communication.Yon may ask why.Well，communication between people contains giving and receiving information.The way we give and receive information today has experienced a revolution in the development of the mass media in the 20th century.The first truly mass communication medium was the newspaper.For the first time in history people could read about events in their country and from around the world every day. However there were two problems with newspapers of that time.Firstly，newspapers were available only in large cities，for getting newspapers to the countryside was a difficult and time-consuming(耗时的)task.Secondly, newspapers weren't always reliable, as there was a limited range of opinions.Nowadays，we can choose from a wide variety of sources to get information.Television and the Internet have given us the chance to be informed about everything the minute it rge numbers of radio and TV stations，satellite channels and millions of websites help people keep up with the latest news.People live in history and are part of it.The media have come a long way in the last century and there is no doubt that we now live in the information age. Whatever type of media we choose，it all comes down to the need for information.This will always be a basic need as long as communication is part of human nature.35．Information is considered the center of human communication because________.A．human communication means information exchangeB．human communication involves people's participationC．information is now experiencing a revolutionD．information helps people gather together36．What was the historical contribution of the newspaper as a source of information?A．It made the mass communication truly develop.B．It helped the mass communication develop in cities.C．It kept people timely informed about home and world events.D．It kept reliable information available in big cities.37．The third paragraph mainly tells us that technology helps________.A．information easily availableB．people be part of historyC．inform everything timelyD．produce the latest news38．It can be concluded from the last paragraph that a basic need today is________.A．communication B．informationC．high technology D．media typesⅣ.短文改错They are some good things about open education. This way of teaching allows the students to grow natural，and to develop their own interests in many subjects. Open education allow students to be responsible (负责) for his own education, as they are responsible for what they do in life. Some students don’t do good enough in a traditional (传统的) classroom. The open classroom must allow them to enjoy learning. Some students will be happy in an open educational school than in traditional classroom. They needn’t worry about grades or rules. For students worry about these things a lot of，it is a good idea to be in an open classroom.答案课时作业(二十一)Ⅰ.1.A考查名词在具体语境中的运用。

Unit 21 Human Biology课时作业Ⅰ.完形填空(2020·内蒙古自治区奋斗中学高三月考)When faced with difficult situations in their lives, many people find them too __1__ and give up, especially on their life dreams.But not for Gabriel Heredia.Gabriel is a 20yearold Argentinian barber who was born without hands. __2__ his physical disability, he was able to grow up happy and __3__. He also always had the support of friends and family, never feeling __4__ treated at all by his schoolmates. At the age of 14, he __5__ working as a barber, and learned all the techniques to perfect haircuts. Although he first saw it as a hobby, Gabriel quickly __6__ that this was the profession he wanted to work in.His family __7__ him to open his first barbershop, which he worked at for one and a half years. There, he __8__ the president of Argentina Corta, an organization for barbers to connect, do charity work in less fortunate __9__， and teach hairdressing to those who are __10__. Gabriel is now part of Argentina Corta, offering his services to people of all __11__ so they can build up the __12__ they need to get decent jobs.As a bright and caring young man, Gabriel __13__ not only to be a barber, but also to make a __14__ with the neighborhood：“The thing that I like most of my __15__ is that people feel comfortable and stylish with my cuts and that makes me __16__.”Nowadays, Gabriel runs his own barber shop in Buenos Aires, where people __17__ around the block for his services. Gabriel's __18__ shows that the barriers we face in life are never __19__ to deal with successfully. Whatever problem you face, you can __20__ tackle it by adopting the right mindset, and never giving up.篇章导读：本文是一篇夹叙夹议文。

Unit 21 Human Biology课时练1 2篇阅读＋1篇完形Ⅰ.阅读理解A(2020·济南模拟)We humans love to stare into our smart devices.We gaze for hours—about 10 hours and 39 minutes a day—at ourcomputers, smartphones, tablets and televisions. Is all thisstaring bad for us? It might be, mainly because as we stare at our devices we are exposing ourselves to blue light.Blue light is a type of electromagnetic(电磁的) radiation with a very short wavelength that produces a high amount of energy. While it’s true that light can damage our eyes under certain circumstances, there’s no scientific evidence suggesting that blue light is harmful to our eyes. But many people still think it is, which is why blue­light­blocking glasses are so popular. So do the glasses work?“Everyone is very concerned that blue light may be causing damage to the eye, but there’s no evidence that it may be causing serious damage，” Dr. Rahul Khurana, clinical spokesman for the American Academy of Ophthalmology, told Business Insider.Blue light exposure is nothing new. In fact, the sun is the largest source of blue light. Moreover, blue light is also present in LED light. But if blue light isn’t harmful, then why are we constantly rubbing our eyes when we’re looking at our screens? The answer is eyestrain (眼疲劳): More than 60 percent of people experience eye problems associated with digital eyestrain. And blue light, it seems, isn’t the cause. Instead, our eyes are so strained because most of us blink less when we stare at our digital devices. So if eyestrain is the issue, blue­light­blocking glasses are probably of little use.【解题导语】该文主要探讨了蓝光是否对我们的眼睛有害的问题。

Unit 21 Human Biology课时作业18 Grammar语法专练(情态动词与虚拟语气)Ⅰ.情态动词1．We can't imagine that two children ________be killed by the washing machine of their house.2．One of our rules is that every student________wear school uniform while at school.3．You________get the machine repaired this week. I won't need it until next month.4．—These grapes look really beautiful.—They________！ See the price $3.99 a pound. Very expensive, aren't they?5．—The deadline is drawing near, but I failed to challenge the task a third time.—________my brother have a try?6．Liza________well not want to go on the trip—she hates traveling.7．—Do you know where David is? I couldn't find him anywhere.—Well, he________have gone far—his coat's still here.8．—Will the book I ordered arrive on time?—It________， if there is no traffic jam.9．You________have bought the book for me, but thank you all the same.10．—Have you heard of the news that Britain's former Prime Minister, Baroness Thatcher, died on April 18?—Yes.________she rest in peace.答案与解析1．should 句意：我们无法想象两个孩子竟然被家里的洗衣机绞死了。

课时作业21 Unit 21 Human Biology课时练(一) 阅读理解·组块专练——练速度(限时：35分钟)阅读理解(共两节，满分40分)第一节(共15小题；每小题2分，满分30分)阅读下面短文，从每题所给的A、B、C和D四个选项中，选出最佳选项。

A[2020·湖北省高考模拟]With its snow­covered mountains and a variety of wildlife, Yellowstone National Park is one of the scenic treasures of the United States. Located primarily in Wyoming, the park hosts millions of visitors every year. If you plan to travel within the park, keep in mind the advice from the National Park Service.Seasonal TravelTravel varies vastly from season to season. Roads are generally open in the summer except for cases of rock or mud slides, wild fires, accidents or road construction. Early snows in the fall can cause some roads to close temporarily. In the winter almost all roads are closed to motor vehicles, but snowmobiles and other snow vehicles with tracks are allowed. Roads begin to open in the spring by the latter part of April but may close if snowfall continues.Driving TimeGrand Loop Road is the main road through Yellowstone National Park, and it passes by most of the major attractions. These include Old Faithful, Yellowstone Lake and the Grand Canyon of Yellowstone. The maximum speed limit on the Grand Loop is 45 miles per hour, but the speed limit drops during some of the winding and twisty sections of this narrow road. Allow yourself at least two days to fully travel the loop due to the size of the park and occasionally heavy traffic.Safety AwarenessBuffalo often block the roads in the park as they migrate through the fields. If a herd is traveling across the road you are on, you can either wait for them to pass or find an alternative route. If you get out of your vehicle, you should stay at least 25 yards from any buffalo (and 100 yards or more away from bears and wolves). Buffalo are particularly unpredictable and charge people at speeds up to 30 mph.You can take your bicycle on any public roads and routes designed for bikes, but bicycles are not allowed on the park roads which are narrow with few shoulders. Elevations range from 5,300 to 8,860 feet. The National Park Service recommends that cyclists wear helmets and noticeable clothing.1．What is TRUE about traveling in the Yellowstone Park?A．Roads will stay open in spite of emergency.B．Traffic jam is actually a rare thing.C．The driving speed on the road can be 50 mph.D．Motor vehicles are allowed in the winter.2．What safety advice does the National Park Service offer?A．Under no circumstances could you get out of the car.B．Keep going forward when coming across the buffalo.C．Do wear easy­to­see clothes while bicycling.D．Bicycling is forbidden on the public roads.3．Where can you probably find this article?A．In a guidebook.B．In a geography textbook.C．In a research paper.D．In a commercial advertisement.B[2020·昆明市教学质量检测]Five­year­old Prisilla Perez, a student at Meador Elementary School in Willis, was unhappy with her recent haircut, which resulted from a severe disease. When students in her class started calling Prisilla a boy, she felt ashamed, often crying and losing focus in school.Her teacher, Shannon Grimm, sympathized with her unhappiness. Grimm and Prisilla's mom were conce rned, but their ideas didn't work.“We had classroom discussions about how girls have short hair and boys have long hair, and I showed them photos of movie stars with different looks，” Grimm said. “However, it wasn't sinking in.”Grimm thought about Prisilla throughout the winter break, and one morning, she had an idea: Cut off her hair — a scary thought for Grimm, who wore her hair long and took pride in it.“I've never had short hair, and I stressed about it for two weeks before making a decision，” she said. On Jan. 4, Grimm invited a hairstylist friend to her home. “I told him to keep going, even if I cried，” she said.The class loved their teacher's new do, especially Prisilla, who excitedly ran off the school bus that afternoon yelling，“Mom, Ms. Grimm cut her hair！” The teacher also bought matching bows for herself and the girl, so they could style their hair together.In February, the teacher recommended Prisilla for the school district's Student of the Month Award, but during the Monday ceremony, she received a surprise“hero medal” from the girl. “Now we have matching awards，” says Grimm.Prisilla's mother, Maria, said that Grimm's thoughtfulness brought her to tears.“I was shocked. I was crying. I couldn't believe it — she did something I wouldn't have the bravery to do. I will never forget that.”4．Why was Prisilla unhappy at school?A．She wasn't satisfied with her teacher.B．She couldn't concentrate in class.C．She was laughed at by her classmates.D．She couldn't get on well with others.5．What made Grimm have her own hair cut?A．Praise from her students.B．Devotion to her students.C．Request of Prisilla's mother.D．Suggestion from the hairstylist.6．What can we know about Grimm?A．She had her hair cut together with Prisilla.B．She expressed her sincere thanks to her pupils.C．She hesitated a lot before having her hair cut.D．She won a gold medal for facing difficulties bravely.7．What is the text mainly about?A．How Grimm helped her student out.B．What problem Prisilla had at school.C．Why Prisilla won the Month Award.D．When Grimm got her new hairstyle.C[2020·武汉调研]While elephants born without tusks (长牙) are not unheard of, they normally form just 2 to 6 percent of the population. However, that is not the case at Mozambique's Gorongosa National Park, where an astonishing 33 percent offemale elephants born after the country's conflict ended in 1992 are tuskless. While that may appear to be just a coincidence, Joyce Poole, an elephant behavior expert, has another theory. The researcher thinks we may be witnessing unnatural evolution of the species due to the constant hunting of elephants for valuable ivory.Poole says before the country's 15­year­long conflict, the park was home to over 4,000 elephants. However, by the time the conflict ended in 1992, about 90 percent of them had been killed for ivory to get money. Of the less than 200 survivors, over 50 percent of adult females had no tusks. Therefore, it is not surprising that the park's tuskless elephant population has grown greatly.This is not the first time researchers have observed a great change in the population of elephants. At Zambia's South Luangwa National Park and Lupande Game Management Area, areas which were heavily hunted in the 1970s and 1980s, 35% of elephants 25 years old or older and 13%of those younger than 25 are now without tusks.A 2008 study published in the African Journal of Ecology found that the number of tuskless females at the Ruaha National Park in Tanzania went from 10.5 percent in 1969 to almost 40 percent in 1989, largely due to illegal hunting for ivory.The recent ban on ivory in both the US and China should help get rid of, or at least reduce, elephant hunting. However, scientists are not sure how long it will take for elephants with a higher rate of tuskless females, to change the_trend.8．What is the probable cause of the phenomenon mentioned in Paragraph 1?A．Illegal hunting. B．Constant farming.C．A pure coincidence. D．Natural evolution.9．Why did people kill so many elephants during the conflict in Mozambique?A．To get money by selling ivory.B．To develop new decorations.C．To provide food for local people.D．To make ivory products.10．Which of the following had the earliest record on tuskless elephants?A．Gorongosa National Park.B．South Luangwa National Park.C．Ruaha National Park.D．Lupande Game Management Area.11．What does the underlined phrase “the trend” in the last paragraph refer to?A．Elephants facing greater danger.B．Elephants growing more slowly.C．Fewer female elephants staying alive.D．More female elephants being tuskless.D[2019·东北三省四市二模]You can't see your sleeping pet's brain waves, but its behavior can tell you when your cat might be dreaming. If you watch closely, you'll see that as she falls asleep, her breathing becomes slow and regular with her body still. She has entered the first stage of sleep, called slow­wave sleep. After about 15 minutes you'll notice a change in her breathing. Her eyes move under her closed lids, her paws twitch (抽动) and she flicks (轻拂) an ear. She has entered dreaming. Although she twitches and makes little grunting noises, messages from her brain to the large muscles in her legs are blocked, so she can't run about. She is in a state of “sleep paralysis (麻痹)”．Michel Jouvet, a French scientist, interrupted their sleep paralysis. Even though they were completely asleep, the dreaming cats began to run for balls that Jouvet couldn't see and arched their backs at unseen enemies. He figured he was watching them act out their dreams! Obviously, the dreaming cats seemed to be practising important cat skills: following, pouncing, and fighting.In another study, Matt Wilson recorded rats' brain waves while they learned mazes. One day, he left the brain­wave­recording machin e on while the rats fell asleep. The pattern of brain waves in the sleeping rats matched the pattern from the maze so closely that Wilson could figure out exactly which part of the maze each rat was dreaming about!Many researchers now think that in both people and animals, one purpose of dreams is to practise important skills and figure out recent learning. This may explain why so many people dream about fighting and escaping, skills that were probably important to our ancestors, and why dreaming affects our ability to learn.Do all animals dream? From looking at the brain waves of sleeping animals, how often animals dream seems to be tied to body size. Cats dream about every 15 minutes, mice every 9 minutes, and elephants every 2 hours. And though cows and horses usually sleep standing up, they only dream when lying down.12．What does Michel Jouvet find in his study?A．The dreaming cats are in a state of body paralysis.B．The dreaming cats often practise their important skills.C．The eyes of dreaming cats moved while bodies are still.D．The legs of the dreaming cats can't move.13．What can you know about dreaming from the passage?A．Dreaming a lot can help humans learn more.B．Learning mazes is the basic skill for cats to learn.C．Rats often dream to work out their recent learning.D．Fighting and escaping are not important skills for ancestors.14．Which animal may dream most frequently?A．Rats. B．Dogs.C．Cows. D．Elephants.15．How does the author develop his passage?A．By making comparisons. B．By using figures.C．By telling stories. D．By showing facts.第二节(共5小题；每小题2分，满分10分)根据短文内容，从短文后的选项中选出能填入空白处的最佳选项。

课时作业21 Unit 21 Human Biology课时练(一) 阅读理解·组块专练——练速度(限时：35分钟)阅读理解(共两节，满分40分)第一节(共15小题；每小题2分，满分30分)阅读下面短文，从每题所给的A、B、C和D四个选项中，选出最佳选项。

A[2020·湖北省高考模拟]With its snow­covered mountains and a variety of wildlife, Yellowstone National Park is one of the scenic treasures of the United States. Located primarily in Wyoming, the park hosts millions of visitors every year. If you plan to travel within the park, keep in mind the advice from the National Park Service.Seasonal TravelTravel varies vastly from season to season. Roads are generally open in the summer except for cases of rock or mud slides, wild fires, accidents or road construction. Early snows in the fall can cause some roads to close temporarily. In the winter almost all roads are closed to motor vehicles, but snowmobiles and other snow vehicles with tracks are allowed. Roads begin to open in the spring by the latter part of April but may close if snowfall continues.Driving TimeGrand Loop Road is the main road through Yellowstone National Park, and it passes by most of the major attractions. These include Old Faithful, Yellowstone Lake and the Grand Canyon of Yellowstone. The maximum speed limit on the Grand Loop is 45 miles per hour, but the speed limit drops during some of the winding and twisty sections of this narrow road. Allow yourself at least two days to fully travel the loop due to the size of the park and occasionally heavy traffic.Safety AwarenessBuffalo often block the roads in the park as they migrate through the fields. If a herd is traveling across the road you are on, you can either wait for them to pass or find an alternative route. If you get out of your vehicle, you should stay at least 25 yards from any buffalo (and 100 yards or more away from bears and wolves). Buffalo are particularly unpredictable and charge people at speeds up to 30 mph.You can take your bicycle on any public roads and routes designed for bikes, but bicycles are not allowed on the park roads which are narrow with few shoulders. Elevations range from 5,300 to 8,860 feet. The National Park Service recommends that cyclists wear helmets and noticeable clothing.1．What is TRUE about traveling in the Yellowstone Park?A．Roads will stay open in spite of emergency.B．Traffic jam is actually a rare thing.C．The driving speed on the road can be 50 mph.D．Motor vehicles are allowed in the winter.2．What safety advice does the National Park Service offer?A．Under no circumstances could you get out of the car.B．Keep going forward when coming across the buffalo.C．Do wear easy­to­see clothes while bicycling.D．Bicycling is forbidden on the public roads.3．Where can you probably find this article?A．In a guidebook.B．In a geography textbook.C．In a research paper.D．In a commercial advertisement.B[2020·昆明市教学质量检测]Five­year­old Prisilla Perez, a student at Meador Elementary School in Willis, was unhappy with her recent haircut, which resulted from a severe disease. When students in her class started calling Prisilla a boy, she felt ashamed, often crying and losing focus in school.Her teacher, Shannon Grimm, sympathized with her unhappiness. Grimm and Prisilla's mom were conce rned, but their ideas didn't work.“We had classroom discussions about how girls have short hair and boys have long hair, and I showed them photos of movie stars with different looks，” Grimm said. “However, it wasn't sinking in.”Grimm thought about Prisilla throughout the winter break, and one morning, she had an idea: Cut off her hair — a scary thought for Grimm, who wore her hair long and took pride in it.“I've never had short hair, and I stressed about it for two weeks before making a decision，” she said. On Jan. 4, Grimm invited a hairstylist friend to her home. “I told him to keep going, even if I cried，” she said.The class loved their teacher's new do, especially Prisilla, who excitedly ran off the school bus that afternoon yelling，“Mom, Ms. Grimm cut her hair！” The teacher also bought matching bows for herself and the girl, so they could style their hair together.In February, the teacher recommended Prisilla for the school district's Student of the Month Award, but during the Monday ceremony, she received a surprise“hero medal” from the girl. “Now we have matching awards，” says Grimm.Prisilla's mother, Maria, said that Grimm's thoughtfulness brought her to tears.“I was shocked. I was crying. I couldn't believe it — she did something I wouldn't have the bravery to do. I will never forget that.”4．Why was Prisilla unhappy at school?A．She wasn't satisfied with her teacher.B．She couldn't concentrate in class.C．She was laughed at by her classmates.D．She couldn't get on well with others.5．What made Grimm have her own hair cut?A．Praise from her students.B．Devotion to her students.C．Request of Prisilla's mother.D．Suggestion from the hairstylist.6．What can we know about Grimm?A．She had her hair cut together with Prisilla.B．She expressed her sincere thanks to her pupils.C．She hesitated a lot before having her hair cut.D．She won a gold medal for facing difficulties bravely.7．What is the text mainly about?A．How Grimm helped her student out.B．What problem Prisilla had at school.C．Why Prisilla won the Month Award.D．When Grimm got her new hairstyle.C[2020·武汉调研]While elephants born without tusks (长牙) are not unheard of, they normally form just 2 to 6 percent of the population. However, that is not the case at Mozambique's Gorongosa National Park, where an astonishing 33 percent offemale elephants born after the country's conflict ended in 1992 are tuskless. While that may appear to be just a coincidence, Joyce Poole, an elephant behavior expert, has another theory. The researcher thinks we may be witnessing unnatural evolution of the species due to the constant hunting of elephants for valuable ivory.Poole says before the country's 15­year­long conflict, the park was home to over 4,000 elephants. However, by the time the conflict ended in 1992, about 90 percent of them had been killed for ivory to get money. Of the less than 200 survivors, over 50 percent of adult females had no tusks. Therefore, it is not surprising that the park's tuskless elephant population has grown greatly.This is not the first time researchers have observed a great change in the population of elephants. At Zambia's South Luangwa National Park and Lupande Game Management Area, areas which were heavily hunted in the 1970s and 1980s, 35% of elephants 25 years old or older and 13%of those younger than 25 are now without tusks.A 2008 study published in the African Journal of Ecology found that the number of tuskless females at the Ruaha National Park in Tanzania went from 10.5 percent in 1969 to almost 40 percent in 1989, largely due to illegal hunting for ivory.The recent ban on ivory in both the US and China should help get rid of, or at least reduce, elephant hunting. However, scientists are not sure how long it will take for elephants with a higher rate of tuskless females, to change the_trend.8．What is the probable cause of the phenomenon mentioned in Paragraph 1?A．Illegal hunting. B．Constant farming.C．A pure coincidence. D．Natural evolution.9．Why did people kill so many elephants during the conflict in Mozambique?A．To get money by selling ivory.B．To develop new decorations.C．To provide food for local people.D．To make ivory products.10．Which of the following had the earliest record on tuskless elephants?A．Gorongosa National Park.B．South Luangwa National Park.C．Ruaha National Park.D．Lupande Game Management Area.11．What does the underlined phrase “the trend” in the last paragraph refer to?A．Elephants facing greater danger.B．Elephants growing more slowly.C．Fewer female elephants staying alive.D．More female elephants being tuskless.D[2019·东北三省四市二模]You can't see your sleeping pet's brain waves, but its behavior can tell you when your cat might be dreaming. If you watch closely, you'll see that as she falls asleep, her breathing becomes slow and regular with her body still. She has entered the first stage of sleep, called slow­wave sleep. After about 15 minutes you'll notice a change in her breathing. Her eyes move under her closed lids, her paws twitch (抽动) and she flicks (轻拂) an ear. She has entered dreaming. Although she twitches and makes little grunting noises, messages from her brain to the large muscles in her legs are blocked, so she can't run about. She is in a state of “sleep para lysis (麻痹)”．Michel Jouvet, a French scientist, interrupted their sleep paralysis. Even though they were completely asleep, the dreaming cats began to run for balls that Jouvet couldn't see and arched their backs at unseen enemies. He figured he was watching them act out their dreams! Obviously, the dreaming cats seemed to be practising important cat skills: following, pouncing, and fighting.In another study, Matt Wilson recorded rats' brain waves while they learned mazes. One day, he left the brain­wave­recording machin e on while the rats fell asleep. The pattern of brain waves in the sleeping rats matched the pattern from the maze so closely that Wilson could figure out exactly which part of the maze each rat was dreaming about!Many researchers now think that in both people and animals, one purpose of dreams is to practise important skills and figure out recent learning. This may explain why so many people dream about fighting and escaping, skills that were probably important to our ancestors, and why dreaming affects our ability to learn.Do all animals dream? From looking at the brain waves of sleeping animals, how often animals dream seems to be tied to body size. Cats dream about every 15 minutes, mice every 9 minutes, and elephants every 2 hours. And though cows and horses usually sleep standing up, they only dream when lying down.12．What does Michel Jouvet find in his study?A．The dreaming cats are in a state of body paralysis.B．The dreaming cats often practise their important skills.C．The eyes of dreaming cats moved while bodies are still.D．The legs of the dreaming cats can't move.13．What can you know about dreaming from the passage?A．Dreaming a lot can help humans learn more.B．Learning mazes is the basic skill for cats to learn.C．Rats often dream to work out their recent learning.D．Fighting and escaping are not important skills for ancestors.14．Which animal may dream most frequently?A．Rats. B．Dogs.C．Cows. D．Elephants.15．How does the author develop his passage?A．By making comparisons. B．By using figures.C．By telling stories. D．By showing facts.第二节(共5小题；每小题2分，满分10分)根据短文内容，从短文后的选项中选出能填入空白处的最佳选项。

Unit 21 Human Biology基础训练Ⅰ.用适当的介词或副词填空1．A volcanic eruption nearly wiped ________ the small island of Montserrat in 1997. 2．I have asked that his proposal be submitted ________ a special committee. 3．I fear that a prior engagement will prohibit me ________ joining you in dinner. 4．All classes in the school are equipped ________ modern equipment.5．You should seek advice ________ your lawyer on this matter.6．I am opposed ________ going shopping with others.7．Some students have not yet submitted their essays ________ their tutors. 8．Pop music is now ________ decline，while country music catches on.答案 1.out 2.to 3.from 4.with 5.from 6.to 7．to 8.inⅡ.完成句子9．They tried their best to make her happy but ________________ (徒劳)．10．The librarian took a book ____________(随便地) from the shelf.11. One failure after another ____________(彻底毁灭) his ambition for fame. 12．Nowadays ________________(对我们学生来说很重要) to master a foreign language. 13．If you had stayed calm yesterday，everything ________________(会很顺利的)．答案9.in vain 10.at random 11.wiped out 12.it is important for us students 13.would have gone smoothlyⅢ.根据短文内容，从短文后的选项中选出能填入空白处的最佳选项。

课时作业42Ⅰ.完形填空In my 40s, as a new solo (独自的) traveller, I spent endless time looking around souvenir shops in tourist areas. It never __1__ me that in shops where merchants weren't __2__ big rents, I could save more money. Besides, I didn't give much __3__ for the size of what I was buying, nor did I care that I would have to take the __4__ to carry it around for the duration of my holidays.I learned and __5__. But I also found that over time, the objects that were __6__ to me changed too. As my tastes matured, my bags got __7__， and so did the time I spent buying cheap goods.In my 50s I __8__ boxes from around the world. Not ordinary boxes but ones __9__ made by artists. These were small so they __10__ easily into every place of my backpack. The __11__ was delightful—the silver from South Korea, the painted camel bone from Egypt and dozens more took up their __12__ in my house.Then a __13__ thing happened. My interest in the collection __14__ while my grandchildren's interest in it grew, so a wonderful and new __15__ began. Each time a child came to visit, he or she was __16__ to pick a box. My popularity __17__ increased among the children, and pretty soon my collection had been __18__ among the little people in our family. Each gift was __19__ by a minitravel story explaining where the __20__ was found, who had made it and what that country was like.本文是一篇记叙文。