题目内容

【题目】根据短文理解,选择正确答案。
As we know, DNA testing is very useful for crime fighting. But now crime fighters could have a new tool at hand. Researchers have developed a cutting-edge (前沿的) technique to identify human hair. Their test is quicker than DNA analysis techniques currently used by the police.
DNA testing is commonly used for identification because DNA is unique to each individual. However, environmental and chemical processes can degrade(降解) DNA, limiting its usefulness over time. Protein (蛋白质) in hair, on the other hand, is more stable than DNA but can also have variations (变异体) that may be unique to the individual.
“Our analysis process can be used universally, ”says Ms. Huang, “One of our samples even included dyed hair and the test was 100 per cent accurate. The test was able to distinguish East Asians, Caucasians and South Asians.”
Dr. Beauchemin says she has got in touch with law enforcement agencies about using the new technology. She is also planning to collect more hair samples and continue her research with a goal of finding where exactly in the world hair sample is from, to look for more races and determine specific age.
“We are in a very similar place with protein-based identification to where DNA testing was during the early days of development,” said chemist Brad Hart. “This method will be a game-changer, and while we've made a lot of progress toward improving it, there are steps to go before this new technique is able to reach its full potential.”
(1)What's the main purpose of the text?
A.To analyze crime scenes.
B.To distinguish different races.
C.To show the usefulness of DNA testing.
D.To introduce a new identification method.
(2)Which will be the most useful in identifying a person according to Brad Hart?
A.Chemical materials.
B.Protein in hair.
C.DNA variations.
D.Blood sample.
(3)What's the advantage of the protein-based identification over DNA testing?
A.Stability.
B.Popularity.
C.Security.
D.Convenience.
(4)What can be inferred from the last paragraph of the text?
A.DNA testing will soon reach its full potential.
B.Protein-based identification remains to be improved.
C.Protein-based identification has replaced DNA testing.
D.DNA testing develops as rapidly as protein-based identification.

【答案】
(1)D
(2)B
(3)A
(4)B
【解析】本文主要介绍了一种比DNA更快捷准确的通过鉴别头发中的蛋白质来侦破犯罪的新科技。

⑴D推理判断题。根据第一段Researchers have developed a cutting-edge (前沿的) technique to identify human hair. Their test is quicker than DNA analysis techniques currently used by the police.和下文的详细描述可知,本文主要是介绍一种比DNA更快捷准确的通过鉴别头发中的蛋白质来侦破犯罪的新科技,故选D。

⑵B细节推理题。根据最后一段“We are in a very similar place with protein-based identification to where DNA testing was during the early days of development,” said chemist Brad Hart.可知Brad Hart认为鉴别一个人最有效的是头发的蛋白质,故选B.

⑶A细节推理题。根据第二段DNA testing is commonly used for identification because DNA is unique to each individual. However, environmental and chemical processes can degrade(降解) DNA, limiting its usefulness over time. Protein (蛋白质) in hair, on the other hand, is more stable than DNA but can also have variations (变异体) that may be unique to the individual.可知,DNA较难保存,容易讲解,而头发中的蛋白质比DNA更加稳定,而且蛋白质也有变异,也可能是个人独有的,所以蛋白质鉴别比DNA鉴别更稳定,故选A。

⑷B推理判断题。根据最后一段“We are in a very similar place with protein-based identification to where DNA testing was during the early days of development,” said chemist Brad Hart. “This method will be a game-changer, and while we've made a lot of progress toward improving it, there are steps to go before this new technique is able to reach its full potential.”可知,通过化学家Brad Hart的话可知这种蛋白质鉴定技术还处于早期发展阶段,如同DNA检测技术的早期阶段一样,还需要不断提高,来充分发挥其潜能。故选B。

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【题目】When a leafy plant is under attack, it doesn’t sit quietly. Back in 1983,two scientists,Jack Schultz and Ian Baldwin, reported that young maple trees getting bitten by insects send out a particular smell that neighboring plants can get. These chemicals come from the injured parts of the plant and seem to be an alarm.What the plants pump through the air is a mixture of chemicals known as volatile organic compounds,VOCs for short.

Scientists have found that all kinds of plants give out VOCs when being attacked .It’s a plant’s way of crying out.But is anyone listening?Apparently.Because we can watch the neighbours react.

Some plants pump out smelly chemicals to keep insects away.But others do double duty .They pump out perfumes designed to attract different insects who are natural enemies to the attackers.Once they arrive,the tables are turned .The attacker who was lunching now becomes lunch.

In study after study,it appears that these chemical conversations help the neighbors .The damage is usually more serious on the first plant,but the neighbors ,relatively speaking ,stay safer because they heard the alarm and knew what to do.

Does this mean that plants talk to each other? Scientists don’t know. Maybe the first plant just made a cry of pain or was sending a message to its own branches, and so, in effect, was talking to itself. Perhaps the neighbors just happened to “overhear” the cry. So information was exchanged, but it wasn’t a true, intentional back and forth.

Charles Darwin, over 150 years ago, imagined a world far busier, noisier and more intimate(亲密的) than the world we can see and hear. Our senses are weak. There’s a whole lot going on.

1What does a plant do when it is under attack?

A. It makes noises. B. It gets help from other plants.

C. It stands quietly D. It sends out certain chemicals.

2What does the author mean by “the tables are turned” in paragraph 3?

A. The attackers get attacked.

B. The insects gather under the table.

C. The plants get ready to fight back.

D. The perfumes attract natural enemies.

3Scientists find from their studies that plants can .

A.predict natural disasters B.protect themselves against insects

C.talk to one another intentionally D.help their neighbors when necessary

4what can we infer from the last paragraph?

A.The word is changing faster than ever.

B.People have stronger senses than before

C.The world is more complex than it seems

D.People in Darwin’s time were more imaginative.

【题目】根据短文理解,选择正确答案。
My parents moved to Mississippi when my brother and I were small children, and we were separated from our Oklahoma grandparents by some 600 miles. This long distance allowed us to only visit our grandparents once a year, either at Christmas or during summer vacation.
Most of my classmates lived near their grandparents, and I would often hear stories of big families regularly spending time with one another, fishing at “grandpa's” house or going over to “grandma's”for her famous fried chicken. We were disappointed that we did not get to spend more time with our grandparents, but our love for them remained deep and strong.
We always expected a road trip to Oklahoma. We would count the days, and when the day came, the entire family would pile into our car at four o'clock in the morning. Crossing the Mississippi River into Louisiana, the scenery changed. Crossing the Red River in Oklahoma, we were in a foreign world.
Every trip to see my grandparents can't be without bringing delight. We jumped out of the car in their driveway to be met with bear hugs. My grandparents wanted to know everything about their grandchildren, and we would sit for hours and tell story after story. Grandma had a meal planned, and you could guess she prepared her grandsons' favorite foods. Of course the best part of the visit was that we were able to do whatever we wanted without punishment from our grandparents. Grandma and Grandpa always had presents for us, short trips planned and lovely surprises, such as the time we got to a local restaurant and ate the world's largest hamburger.
(1)Why didn't the family visit their grandparents often?
A.Because they seldom had a vacation.
B.Because they had a bad attitude to them.
C.Because they were all busy with their work.
D.Because they lived far away from each other.
(2)When hearing his classmates' stories, the author __________.
A.often felt deep sorrow
B.would call his grandparents
C.would admire them at heart
D.would feel sorry for his poor life
(3)Whenever the author and his brother met their grandparents, they _________.
A.were full of great excitement
B.found they were in a foreign world
C.shared cooking skills with each other
D.seemed not to be familiar with each other
(4)What can we infer from the author's story?
A.Distance can't break the bond of love.
B.Physical separation hurts the heart deeply.
C.Distance leads to the most beautiful scene.
D.Family life is filled with love and understanding.

【题目】阅读下面短文, 从短文后各题所给的四个选项(A、B、C、D)中, 选出可以填入空白处的最佳选项。
Once upon a time, there lived two parent parrots. Every morning they flew out to 1 food for their two young birds. One day, a hunter 2 the young birds. The young birds 3 to free themselves from the hands of the hunter. One 4 from the hunter, while the other was taken in a cage by the hunter to his house. He gave it to his 5.
The other parrot flew away and came to a place where some holy men lived. They did not 6 the young parrot, so it stayed there. It 7 their talk and learned to say a few words.
Several years later, a traveler was walking near the hunter's hut(小屋). He sat near the hut, extremely 8. He heard the parrot that lived there say, “9, why have you come here? I will cut your throat.” The traveler 10 got up and left the place in a hurry. Then he happened to reach the place where the other parrot lived. The parrot was sitting on a tree. Seeing the traveler, it said, “Welcome, traveler. Welcome to this hermitage(偏僻的寺院). We have a lot of good 11 in this forest, which looks sweet and delicious. Eat whatever you like. The holy men will 12 you well.”
The traveler was 13. He couldn't understand why this parrot was so polite 14 the other one was so rude. They were both parrots, after all. 15 it wasn't strange. The parrot he met first lived with the hunter's children who often spoke 16 words, while the parrot he met later had learned the 17 of holy people.
Our growing environment is of great 18. It is the company that shapes our words and deeds. Good company helps us learn good things while bad company 19 the contrary. Therefore, choose the 20 people to grow up with.
(1)A.get B.preserve C.cook D.buy
(2)A.defeated B.threatened C.caught D.observed
(3)A.flew B.screamed C.advanced D.struggled
(4)A.disappeared B.learned C.escaped D.died
(5)A.cousins B.kids C.neighbors D.parents
(6)A.harm B.follow C.know D.demand
(7)A.looked for B.cared for C.referred to D.listened to
(8)A.disappointed B.tired C.concerned D.excited[
(9)A.Father B.Officer C.Fool D.Sir
(10)A.suddenly B.gradually C.hardly D.immediately
(11)A.rice B.fruit C.meat D.bread
(12)A.treat B.understand C.guide D.protect
(13)A.interested B.thrilled C.surprised D.relaxed
(14)A.though B.unless C.as D.while
(15)A.Necessarily B.Actually C.Fortunately D.Strangely
(16)A.dirty B.short C.dishonest D.amazing
(17)A.language B.joy C.attitude D.experience
(18)A.difference B.shock C.value D.importance
(19)A.picks up B.consists of C.leads to D.makes up
(20)A.lucky B.right C.kind-hearted D.educated

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