C ★★★★★ Elephants have strong defenses against cancer that can prevent it forming,say scientists. They were trying to explain why the animals have lower levels of cancer than would be expected consider 题目和参考答案——青夏教育精英家教网—

题目内容

★★★★★

Elephants have strong defenses against cancer that can prevent it forming,say scientists. They were trying to explain why the animals have lower levels of cancer than would be expected considering their size.

People think that every cell can become cancerous,so the more of them you have,the more likely you are to get cancer. So if an elephant has 100 times as many cells as a person,then it should be 100 times more likely to have the disease. And yet the analysis showed only 5% of elephants die from cancer compared to up to 25% of people.

The scientists turned to elephants’ DNA. Cancer is caused by mutations (变异) in a ceir s DNA that produce faulty instructions leading to (遏制不住的) growth. But animals also have “smoke alarms” that detect the damage and lead to the cell being repaired or killed. One of these alarms is called TP53,and while humans have one TP53 gene,elephants have 20.As a result,elephants seem far keener to kill off cells.

But Mel Greaves,from the Institute of Cancer Research in London,said, “We should focus on why humans have such high levels of cancer. In terms of adaptive mechanisms (机制) against cancer we have the same as chimps,but a lot more humans get cancer than chimps. I think the answer is that humans are completely unique as a species in having very rapid social evolution (进化) in a short period of time." He pointed to the rise of unhealthy,cancer-causing behavior,such as obesity and sunbathing. “You’ve never seen an elephant smoke!” he added.

In an evolutionary sense, “success” is judged by the number of kids you have rather than how long you live. Elephants have the greatest reproductive success towards the end of their lives,while humans can live for decades after we are no longer able to getting pregnant. It means there is little evolutionary pressure in humans to develop ways of preventing cancer in old age.

9. What is the text mainly about? ，

A. When elephants will get ill.

B. How elephants live a long life.

C. What elephants do when having cancer.

D. Why elephants have slight chances of getting cancer.

10. Why are elephants keener to kill off cells compared with humans?

A. They are larger in size.

B. They have a unique alarm.

C. They have more TP53 genes.

D. They have healthier eating habits.

11. In the eyes of Greaves, .

A. chimps get more cancer than humans

B. humans* unhealthy behavior increases cancer risk

C. chimps have better adaptive mechanisms than humans

D. elephants have more rapid social evolution than chimps

12. When elephants become old,they will .

A. fall into bad habits

B. suffer from various diseases

C. go on producing baby elephants

D. have less evolutionary pressure

9. D 10. C 20. A 11. B 12. C

C篇

研究发现,体型庞大的大象很少受到癌症的困扰。

9. D.主旨大意题。从全文整体看，本文分析了大象为什么很少受到癌症困扰的原因，故选D项。

10. C.推理判断题。根据第三段中的one of these alarms is called TP53 …elephants have 20. As a result,elephants seem far keener to kill off cells bI 知，与人类相比大象体内有更多的TP53.所以对杀死细胞更灵敏。

11. B.推理判断题。根据第四段中的内容可知，人类的不良生活习惯是引起癌症多发的因素之一。

12. C.细节理解题。根据最后一段中的ElePhants have the greatest reproductive success towards the end of their lives可知，大象即使年迈后仍会生育小象。

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相关题目

阅读下列短文，从每题所给的四个选项(A、B、C和 D) 中，选出最佳选项。

★ ★ ★ ☆ ☆

I grew up in Philadelphia,Pennsylvania with my mother and elder sister. While we weren't rich,my mother managed to provide us with more than we needed and quite a bit of what we wanted. We had ups and downs,but mostly ups. One of my mother's favorite things to say was, “Well,try it and see." As a carefUl little girl,her words didn't do much to make me a real explorer of anything other than good books. However,my mother's words encouraging me to try harder,to climb and to reach new heights finally worked one day.

In December,2015,I had the extreme pleasure of visiting the South Pole,Antarctica to be exact. I once thought it would be the last place on the earth that I'd ever visit. First of all,I didn't vacation in a cold place. Second,if I did,it would be more like a lodge(乡间小屋) on a mountain with a hot bathtub and a warm fire. But I went there.

It was a ten-day cruise that .produced more highs than I could have ever imagined. It was the longest time I'd ever been away from my children. I missed them so much that I had a few mild meltdowns(崩溃) ，but I recovered quickly after seeing a family of four crabeater seals swim right up below my deck. Somehow that moment of missing my children was soothed(抚慰) by God's wonderful works.

When I reached the highest point of Cuverville Island, after a scary and long trip up,I felt I had done something very meaningful. It was a journey for moms,for new entrepreneurs(企业家) and for the little girls who would dream bigger and do better because we showed them they could.

1. When the author was young,her mother liked .

A. reading books B. complaining a lot

C. encouraging her D. exploring new places

2. What did the author once show no interest in?

A. Going on vacation. B. Going to Antarctica.

C. Getting new things. D. Reading good books.

3. How did the author react when seeing the four crabeater seals?

A. She felt a lot better.

B. She burst into tears.

C. She wanted to touch them.

D. She missed her children even more.

4. What did the author think of her journey?

A. Costly. B. Relaxing.

C. Inspiring. D. Disappointing.

★★★★☆

In 2014 and 2015,a Gallup World Poll surveyed people m 119 countries. A group of scientists analyzed how people answered two of the questions: How much do you know about global warming,and how serious was it to you and your family? And they were surprised.

Most scientists think the world's climate changing fast,yet many people do not share the scientists,view.What's more,how people responded depended on various reasons. These included where people livd,how;many years they'd gone to school,how much money they earned,their gender — even things such as how polluted the air was in the place where they lived. It's the first time those have been studied for their possible link to people' s thoughts on climate change.

Many people were not even aware of global warming. Most people in Africa and the Middle East had!never heard of the concept. In contrast,people in the wealthier and more highly educated nations were quite familiar with global warming. Among people who were ： aware of global warming,those in the poorer nations i tended to judge it as a far bigger threat. And in Latin Amenca and Europe people were more likely to see global warming as a bigger menace (威胁) when they understood the role that humans have played in that ： warming. In Africa people were more likely to see :

climate change as a risk if it was tied to local temperatures or air pollution.

“To our knowledge,this is the first and only truly global study,”according to the study's lead author Lee.; Lee says the new analysis indicates that there's still much work to do to get the word out about global warming. Indeed,helping people in different parts of the globe understand it may require explaining the data and risks in;very different ways. Those explanations might have to differ from one neighboring country to another.

5. What surprises scientists according to the text?

A. People's different opinions on climate change.

B. Different causes of global warming.

C. The seriousness of global warming.

D. The fast pace of climate change. t

6. What can we infer from Paragraph 3 ?

A. Africa has suffered severe air pollution.

B. In Europe most people have studied climate change.

C. Most people knew about the reasons for global;warming.

D. Highly educated people were more aware of global wanning.

7. What does Lee learn from the research findings?

A. It takes more effort to popularize global warming.

B. Global warming will need more data to prove.

C. Global warming puts people at great risk.

D. It's difficult to stop global warming.

8. Where does this text probably come from?

A. A lesson plan. B. A news report.

C. A fashion magazine. D. A tourist guidebook.

Hip-hop music doesn’t typically remind us of the description “kid-friendly”. But Syracuse musicians Samar Moseley and Tyrone Jackson have found inspiration in their work as bus drivers for the Syracuse City School District. While other performers may rap about street violence or ill-gotten riches,this pair — known as 1306 — apply catchy beats to cautionary raps on bus safety and working toward graduation.

Last year,1306 put out a three-song record,Mr. Bus Driver,with positive raps on school-related issues. They also performed at city schools. In an interview,Moseley said that he thought 1306 could find a sizable market for its positive messages. Moseley is the songwriter while Jackson handles the beats and engineering. The pair,who started driving buses in 2011,are enthusiastic about what the foture holds.

They met during their bus driver training. The name 1306 came from Moseley's Bus Route 13 and Jackson's Bus Route 06. The concept behind that is going down a new journey and taking a new route to success. The first songs they did were club songs. One day,they both had a bad day on the bus,so they started talking about what happened and came up with the Mr. Bus Driver song.

“Driving a school bus isn’t an easy job. You have to let kids on the bus know that there are rules they should follow. The best way to teach something is to make it constructive and fun. Kids can learn the rules and have fun singing songs and dancing. It's a good feeling,” Jackson said. .

Their CDs have now become popular in other states. In Minneapolis,people play them in day care centers. After more than a year,1306 is still the only thing the kids in the centers want to listen to.

9. What makes 1306 different from other rappers?

A. Their club songs.

B. Their sunny smiles.

C. Their special experiences.

D. The themes of their songs.

10. Why did Moseley and Jackson choose the name 1306?

A. It was their new bus route number.

B. It combined their bus route numbers.

C. It reminded them of their bad days.

D. It is the combination of their birthday dates.

11. What's the purpose of 1306’s songs according to Jackson?

A. To comfort bored drivers.

B. To make kids learn music.

C. To teach people how to drive.

D. To help,kids behave themselves.

12. How is the last paragraph developed?

A. By time. B. By contrast.

C. By example. D. By space.

★★★★☆

Kashy Keegan is a British singer and songwriter. He is best known for his song This Is My Dream.

Keegan was bom on July 18 ,1983 in England. He wrote This Is My Dream in 2007. The song was originally a London 2012 Olympics motivational song and was later discovered by a music supervisor(音乐总监) after Keegan had (上传) it to the website The song was chosen as the theme music for a documentary series called The Challenge. And on October 27 ,2013,about 30,000 people watched Keegan perform his song This Is My Dream in Hong Kong,China. The song reached the number 1 position on a music chart outselling major international artists like Lady Gaga,Katy Perry and Justin Bieber.

“I wrote that song seven years ago,and had never performed it,J, says Keegan,who by that time had given up on a musical career after 15 years of doing other jobs to pay for studio time. “That's the (奇异可笑之处) of life,I guess. Things happen when you least expect it."

Keegan has released two albums independently Kashy Keegan and Looking In until now. He moved to Hong Kong,China to pursue his music career and signed to a record label Evosound in May 2014 and released an album This Is My Dream on December 1 ,2014r He writes and produces all of his own material and is influenced by classic pop music. He says his favorite album is Tracy Chapman by Tracy Chapman because of its socially conscious lyrics.

When asked to describe his own music,Keegan uses the words “inspiringM and “empowering” before reluctantly admitting that UI guess it is pop,but …deeper."

Clearly,he values (实质) over style. “For me,an artist is not so much how well he sings; it's having the genuine heart behind that,” he says.

5. What do we know about This Is My Dream?

A. It failed to reach No. 1 on a music chart.

B. It was the 2012 London Olympics theme song.

C. It was uploaded to the website by a music supervisor.

D. It was chosen to be the theme music for The Challenge.

6. What Keegan says in Paragraph 3 means .

A. he hates paying a lot for studio time

B. he will never give up his musical career

C. he is surprised by the success of his song

D. he has devoted himself to music for seven years

7. The underlined word ^pursue^ in Paragraph 4 can be replaced by .

A. prove B. develop C. abandon D. complain

8. Which album does Keegan like best?

A. Looking In. B. Kashy Keegan.

C. Tracy Chapman. D. This Is My Dream.

★★★☆☆

Reading is important for children to grow up. If you want touching or funny or unusual or classic picture books,there are some books to excite your interest.

The Day the Crayons Came Home

by Drew Daywalt,illustrated by Oliver Jeffers

Duncan has some interesting crayons. Mine just sit there until I use them to color things. Duncan's crayons,however,get fed up and leave home or take adventures. They* re anything but dull. If your child loved The Day the Crayons Quit,this newest colorful adventure should be at the top of your reading list.

Little Red Gliding Hood

by Tara Lazar,illustrated by Troy Cummings

The newest take on Little Red Riding Hood is a fairy tale full of fun. Little Red needs a new pair of ice skates,but the only way to get them is to win a competition. With most of the fictional characters having partners,she may need to team up with someone unexpected.

Finding Winnie

by Lindsay Mattick,illustrated by Sophie Blackall

Most of us are familiar with Christopher Robin and Pooh Bear,but few people realize that Pooh grew out of the imagination of A. A. Milne who was a playwright and was inspired to write stories for his son Christopher Robin. In 1914,a vet named Harry Coleboum rescued a baby bear,took it to war with him,and later brought him back to England and then to the London Zoo where the bear met the real Christopher Robin. The rest,as they say,is history.

Swan: The Life and Dance of Anna Pavlova

by Laurel Snyder,illustrated by Julie Morstaa

Aspiring dancers will be fascinated by both the story and artwork of Swan. The story captures a small girl's enchantment(着迷) with ballet and her rise to become one of the world's most respected woman dancer in ballet.

13.Which of the following books is illustrated by Troy Cummings?

A. Swan: The Life and Dance of Anna Pavlova.

B. The Day the Crayons Came Home.

C. Little Red Gliding Hood.

D. Finding Winnie.

14. The book Finding Winnie tells the story of.

A. a little girl B. a baby bear

C. some swans D. A.A. Milne

15. Who wrote the book about a ballet dancer?

A. Lindsay Mattick. B. Drew Daywalt.

C. Laurel Snyder. D. Tara Lazar.

16. The main purpose of the text is to .

A. introduce four picture books

B. inspire us to write a picture book

C. encourage children to buy the picture books

D. tell us the importance of reading picture books

★★★★☆

Most people consider mushrooms to be the small,ugly cousins of the plant kingdom,but some of them are surprisingly beautiful and wonderful waiting to be explored.

Sky Blue Mushroom

Sky Blue Mushroom is a species of mushroom found in New Zealand and India. The small mushroom has a distinctive all-blue color,while the (菌褶) have a slight reddish color. Sky Blue Mushroom is not eatable because it is poisonous. This species was one of the six native fungi (真菌）featured in a set of fungal stamps issued in New Zealand in 2002. It is also seen on the $50 bank note issued by the Reserve Bank of New Zealand in 1990.

Veiled Lady Mushroom

This delicate and strange mushroom can be found in gardens and woodlands in southern Asia,Africa,Australia and the Americas. This eatable and rather healthful mushroom is used in Chinese cuisine. While the lacy （似蕾丝的) skirt is what draws our eyes,the mushroom actually uses the cap to draw attention,too.

Bioluminescent Fungi

This green mushroom emerges during the rainy season in Japanese and Brazilian forests. The bases of tree trunks,fallen branches,leaf litter and slightly wet soil provide perfect growing grounds for the mushroom. The appearance of these bright-looking fungi is due to bioluminescence (生物发光) , one of the strange but wonderful reactions that happen naturally in many plants and animals.

Red Cage Fungus

The mushroom is known as the red cage,referring to the striking fruit body that is round and empty inside with latticed(花格状的) branches. Feeding off woody plant materials,this mushroom can be found growing in leaf litter,grassy places or on garden soil. Though it isn’t clear if it is eatable,apparently its smell is enough to prevent anyone interested from eating it.

13. What do we know about Sky Blue Mushroom?

A. It's eatable and healthful.

B. It's blue with a slight reddish color.

C. It's seen on some Indian bank notes.

D. It's the only flmgus appearing in stamps.

14. Which of the following would be Veiled Lady Mushroom?

15. Where can we probably find Bioluminescent Fungi?

A. In Japan. B. In Australia.

C. In New Zealand. D. In southern Asia.

16. From the text,we can know that .

A. Sky Blue Mushroom attracts people by its special cap

B. Veiled Lady Musbroom also emerges in Brazil and Africa

C. Red Cage Fungus can be found in gardens with a bad smell

D. Bioluminescent Fungi are sometimes used in Chinese cuisine

2. 我们都佩服他事业有成。 (admire)

情景交际(每小题1分，共5分)

根据对话内容，从方框中选择恰当的选项补全对话，其中有两项多余。

A: Hi,Mary. Welcome to the show. You like exploring (探险) ，doh’t you?

B: (46) And I just went on an adventure (冒险）

A: Tell us about it.

B: I went on a night tour at the zoo. It's called Night Adventure.

A: (47)

B: Oh no. There’ re lots of animals awake at night.

A: Wow. OK,Mary. (48)

B: I went with my guide.

A： (49)

B: We saw bears walk up and down and tigers look around on a rock. Many forest animals woke up at night.

A: Really? (50)

B: I was really scared.

A. How did you feel when you saw that?

B. Tell us what you saw.

C. Who did you go with?

D. Where are they from?

E. That's right.

F. It sounds good.

G. Aren’t all the animals sleeping at night?

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