Unit5 Developing ideas and Presenting ideas 能力提升练
Ⅰ.阅读理解
(2020黑龙江哈尔滨第六中学高二上期末）
People have been wondering why elephants do not develop cancer even though they have lifespans that are similar to humans，living for around 50 to 70 years.
Now scientists believe they know why. A team at the University of Chicago has found that elephants carry a large number of genes that stop tumors developing. To be precise, they found 20 copies of an anti-tumor gene called TP53 in elephants. Most other species, including humans, only carry one copy.
According to the research，the extra copies of the gene improve the animal’s sensitivity to DNA damage, which lets the cells quickly kill themselves when damaged before they can go on to form deadly tumors.
“An increased risk of developing cancer has stood in the way of the evolution (进化）of large body sizes in many animals,” the study author Dr. Vincent Lynch told The Guardian. If every living cell has the same chance of becoming cancerous, large creatures with a long lifespan like whales and elephants should have a greater risk of developing cancer than humans and mice. But across species, the risk of cancer does not show a connection with body mass.
This phenomenon was found by Oxford University scientist Richard Peto in the 1970s and later named “Peto’s paradox”. Biologists believe it results from larger animals using protection that many smaller animals do not use. In the elephant’s case, the making of TP53 is nature’s way of keeping this species alive.
The study also found that when the same genes were brought to life in mice, they had the same cancer resistance as elephants. This means researchers could use the discovery to develop new treatments that can help stop cancer spreading or even developing in the first place.
“Nature has already figured out how to prevent cancer,” said Joshua Schiffman，a biologist at the School of Medicine, the University of Utah. “It’s up to us to learn how different animals deal with the problem so that we can use those strategies to prevent cancer in people.”
1.Why are elephants unlikely to develop cancer
A. They have a rather large body size.
B. Their genes suffer no DNA damage.
C. Certain genes in their body kill existing tumors.
D. They carry many genes to prevent tumors developing.
2. According to the passage, what has been a risk in the evolution of large animals
A. Deadly tumors.
B. The huge body mass.
C. Cells killing themselves.
D. Sensitivity to DNA damage.
3.What does the underlined part “This phenomenon” in Paragraph 5 probably refer to
A. Larger animals have protection from TP53.
B. The risk of cancer is not related to body sizes.
C. Larger animals suffer the same risk of cancer as smaller ones.
D. The huger animals are, the bigger risk of cancer they will have.
4.What can be concluded from the passage
A. Depending on nature is surely enough to fight against cancer.
B. The TP53 genes have proved useful in stopping cancer in people.
C. Humans are expected to prevent cancer with the making of TP53.
D. The extra copies of elephants，genes are used to cure cancer patients.
Ⅱ.七选五
(2020河南洛阳第一高级中学高二下周测）
Farmers, especially in developing countries, are often criticized for cutting down forests. But a new study suggests that many farmers recognize the value of keeping trees.
Researchers using satellite images found at least ten percent trees cover more than one billion hectares of farmland. 1
The study found the most tree cover in South America. 2 North Africa and West Asia have the least. And it also found that climate conditions alone could not explain the tree cover in different areas.
3 There are areas with few trees but also few people, and areas with many trees and many people. The findings suggest that things like land rights, markets or government policies can influence tree planting and protection.
Dennis Garrity heads the World Agroforestry Center. 4 The problem, he says, is that policy makers and planners have been slow to recognize this and to support such efforts.
The satellite images may not show what the farmers are using the trees for，but trees provide nuts, fruit, wood and other products. They provide windbreaks and shade. 5 Even under drought conditions，trees can often provide food and a way to earn money until the next growing season.
A. Almost all of it is covered by trees.
B. Nor could the size of nearby populations, meaning people and trees can live together.
C. He says farmers are acting on their own to protect and plant trees.
D. He devotes most of his time to making people realize its importance.
E. Next comes Africa south of the Sahara, followed by Southeast Asia.
F. They also help prevent soil loss and protect water supplies.
G. That is almost half the farmland in the world.
1.________ 2._______ 3.________ 4.________ 5.________
Ⅲ.读后续写
（2020湖北沙市中学高二上期末）
阅读下面材料，根据其内容和所给段落开头语续写两段，使之构成一篇完整的短文。续写的词数应为150左右。
The event that stands out in Tom’s memory happened one morning when Tom was only ten years old. He was at home with his elder sister Jane. Tom was doing his homework when he heard raised voices.
At first he thought nothing of it since customers in the motorcycle shop directly below their flat often became loud, but he soon realized this time it was different.
“Quick! Quick! Remove the motorcycles from the shop,” someone yelled.
Then a thick burning smell filled the air. When Tom opened the front door of their flat to investigate, a thick cloud of smoke greeted him. The motorcycle shop had caught fire and people were running and crying.
Jane, who had been playing the violin in her room，hurried to the living room. They rushed out of the door and along the corridor through the smoke.
They were heading towards the stairway at the far end of the corridor when Jane stopped in her track. She turned around and headed back the way they came. Tom had no idea what she was doing, but he followed suit.
Jane had suddenly remembered the lady in her 70s who lived next door to them, who they called Makcik, Malay for auntie. Jane began banging on Makcik’s door, but got no answer. As the smoke thickened around them, Tom could see many of their neighbors—some still in their pajamas—running for safety. The thought of fear crossed his mind.
“She would have run for safety like everyone else!” Tom cried. However, Jane refused to give up, “I know Makcik’s still inside.” She said she was familiar with Makcik’s daily routine and was certain she would still be sleeping. She pounded (重击）at the door. “Go downstairs. Go now! Go!”
Paragraph 1
Tom noticed the flame was reaching up. ________________________________ ______________________________________________________________________________________________________________________________________________________________________________________________________________
Paragraph 2:
Luckily, some neighbors passing by stopped and offered help._________________ ____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________
参考答案：
Ⅰ. 语篇解读:本文主要介绍了美国芝加哥大学的一个团队发现大象携带大量阻止肿瘤发展的基因。在动物的进化中肿瘤是极大的威胁，而物种患癌症的几率和它们的体型没有关系。在大象的案例中，TP53的形成是让这个物种存活的自然方法，因此人们有望通过合成TP53来预防癌症。
1. D 细节理解题。根据第二段第二句 A team at the University of Chicago has found that elephants carry a large number of genes that stop tumors developing.可知，美国芝加哥大学的一个团队发现大象携带大量阻止肿瘤发展的基因，所以D选项是正确的。
2. A 推理判断题。根据第四段第一句“An increased risk of developing cancer has stood in the way of the evolution（if）of large body sizes in many animals,” the study.可知，在大体型的动物的进化中，患癌症的风险增加。由此可知，它们进化中致命的肿瘤是极大的威胁，所以A选项是正确的。
3. B 推理判断题。根据第四段最后一句 But across species，the risk of cancer does not show a connection with body mass.可知This phenomenon指的是物种患癌症的几率和它们的体型没有关系，所以B选项是正确的。
4. C 主旨大意题。根据最后一段最后一句 It's up to us to learn how different animals deal with the problem so that we can use those strategies to prevent cancer in people可知，我们可以使用那些策略来预防人类得癌症。而根据倒数第三段最后一句I the elephants case，the making of Tp53 is natures way of keeping this species alive.可知，TP53的形成是让大象存活的自然方法。由此推知，人们有望通过合成TP53来预防癌症。所以C选项是正确的。
Ⅱ.语篇解读：文章介绍了现在世界上农田树林占有的面积还是很大的，农民正意识到树木对人和环境的重要性。
1. G 根据设空处的前一句“Researchers using satellite images found at least ten percent trees cover more than one billion hectares of farmland.”可知，此处在说树木在农田中的覆盖量的问题，G项“那几乎是世界上农田的一半。”符合上下文语
境。故选G。
2. E 根据设空处前后可知，此处在说树木在世界各地的覆盖率的排名。E项“接下来是撒哈拉以南的非洲，然后是东南亚。”符合语境。故选E。
3. B 根据设空处的前一句“And it also found that climate conditions alone could not explain the tree cover in different areas.”可知，此处在讲述造成不同地区树木覆盖率不同的因素。B项“附近的人口规模也不能意味着人和树木可以共存。”是在讨论人口和树木的关系，符合上下文语境。故选B。
4. C 根据设空处后一句“The problem，he says，is that policy makers and planners have been slow to recognize this and to support such efforts.”可知，问题在于政策制定者和规划者迟迟不承认这一点，并不支持这种努力。C项“他说农民们正在采取行动独自保护和种植树木。”讲的是现在农民做出的努力，与后文承接，故选C。
5. F 根据设空处所在段的内容可知，这里在讲述树木的用途，F项“它们还有助于防止土壤流失和保护水供应。”也是树木的一个重要作用，所以F项内容符合上下文语境，故选F。
Ⅲ. One possible version:
Paragraph 1:
Tom noticed the flame was reaching up. Frozen with fear, he stood rooted to the spot. He comprehended the gravity of the situation and held Jane's hand tightly. By then, both of them were coughing and their eyes were stinging. Time seemed to stand still though they were probably there for only two or three minutes. Tom begged Jane to run for safety as quickly as possible. Jane tried to shield her nose from the choking smoke and shook her head. She kept pounding against the door. Tom burst out crying. Paragraph 2:
Luckily, some neighbors passing by stopped and offered help. A sense of strength immediately replaced the mounting fear and anxiety in Janes mind. She told them Ms. Makcik must be still in the room. They forced the door open with all their might. Sure enough. Makcik was lying in bed, unconscious. She was carried downstairs and then rushed to the hospital, where she finally came to herself. People in the neighborhood felt relieved and Jane and Tom' s Joy was immense.
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