题干

   Scientists are debating how to limit their newly-discovered power to change genetic structure. Scientists have already changed the genes of farm animals and agricultural plants to make them more productive or stronger. But now they can also change genes in wild animals and plants. These genes would continue into later generations. For example,it may be possible for scientists' to remove from existence the kind of mosquitoes that carry the Zika virus. They might also be able to permanently remove species of plants and animals that are destructive to other species.

In a report published last week,the U.S. National Academies of Sciences,Engineering and Medicine said it supports continuing research on this kind of gene control. But it warned that it is not possible to know what will happen when these changed plants and animals are released into the wild.

Sixteen biologists,ethicists(伦理学家)and policymakers are on a National Academy of Sciences(NAS)committee that is examining the issue. They say that there is value to the new technology. But,they say,there is not enough evidence to support the release of changed organisms(生物)from the laboratory into nature.

Many people would support stopping mosquitoes and rats from carrying diseases. But scientists say we must understand the possible scientific,ethical,legal and social results of such action before we decide whether to take it. Gene modification is spread through reproduction(繁殖).Changed genes will continue to spread as long as an animal or plant continues to reproduce. They cannot be limited to a farm or kept within a country's borders. Scientists are wondering what may happen if a changed organism mates with another species. They are not yet sure how the changed genes would affect the other species. It is possible that those genes could harm those creatures or even lead to their disappearance from our planet.

【小题1】What possible advantage does gene control in wild animals and plants have?
A.Changing the Zika virus permanently.
B.Removing the destructive species forever.
C.Having changed genes in their next generations.
D.Making all the species more productive and stronger.
【小题2】Which of the following is NOT true according to the passage?
A.Scientists are not sure what exact results gene modification leads to.
B.Scientists won't change any genes before they make the final decision.
C.Gene modification has benefited some farm animals and agricultural plants.
D.Scientists have not applied gene modification to wild animals and plants in case of possible danger.
【小题3】As for genetically changed wild animals and plants, what are scientists worried about?
A.They may become weaker or die out.
B.They may be more productive.
C.They may cause damage to their living habitat.
D.Their genes may spread to later generations.
【小题4】What can be the best title for the passage?
A.Stop research on gene control
B.How to change genetic structure
C.Power and danger of gene control
D.Advantages of gene control in wild animals and plants
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同类题2

   Driverless technology will soon enter another major global industry: shipping. Several companies recently announced plans to launch self-sailing ships to improve safety and efficiency.

One of them is the Norwegian chemical company Yara International. Yara has teamed up with another Norwegian company, Kongsberg, to build an autonomous goods ship expected to be launched next year.

Kongsberg developed the ship's electrical technology and autonomous control systems. The ship is fully electric to reduce air pollution. It is designed to carry goods containers normally transported by truck. This means the ship will also improve road safety by replacing about 40, 000 truck trips a year. The company plans to operate the ships by far-away control beginning sometime next year. By 2020, the ships should be loading and sailing themselves. While Yara's ships will be limited to Norway at first, the company plans to greatly expand its autonomous shipping operations in the coming years.

Another company putting a high priority(优先)to self-sailing ships is the world's largest mining company, Australia's BHP Billiton. The company's Vice President of Freight, Rashpal Bhai, recently spoke about the technology in a website post. Bhatti believes automation will be one of the biggest changes for shipping in the future. He said, "Autonomous ships offer important opportunities to improve safety and provide more effective results to the supply chain of the sea. "He added that self-sailing ships could become a reality within the next decade.

Rolls-Royce, the British automobile and engine manufacturer(制造商), is also developing unmanned(无人驾驶的)shipping technologies. Oskar Levander is the company's head of operations at sea. He said in a conference last year, "This is happening. It's not if, it's when. "

Levander said these autonomous ships could be controlled by far-away operators from anywhere. He added, "Because these ships will be designed to be unmanned, they can be built smaller, more efficient and environmentally friendly. "

【小题1】Why have several countries announced plans to produce self-sailing ships?
A.To save money.
B.To develop electrical technology in ships.
C.To compete in autonomous control systems.
D.To make shipping more effective and less risky.
【小题2】What do Oskar Levander's words suggest in Paragraph 4?
A.It is too early to make autonomous ships.
B.The supply chain of the sea will be busier.
C.People are more concerned about autonomous ships.
D.Unmanned shipping technologies are becoming more mature.
【小题3】What would be the best title for the text?
A.Automation in Sail
B.Self-sailing Ships in Use
C.Automation in Some Fields
D.Automation in Imagination

同类题3

   Nature has its own way of balancing itself out,but when we humans get involved,we tend to throw things out of control. Forests and oceans are natural carbon sinks that absorb carbon dioxide from the atmosphere, but since we’ve been pumping too much into the air, those sinks can’t keep up. Scientists at the Max Planck Institute for the Advancement of Science in Germany, led by biologist Tobias Erb,have figured out a way to supercharge plants to make them better at absorbing carbon dioxide, which could be a key defense against climate change.

Erb and his team figured out a way to make plants more efficient(效率高的)at absorbing carbon, so that they consumed more carbon in a shorter amount of time. “If you think about plants, they are efficient carbon dioxide -fixing filters, but they are not fast,” Erb said. “I think there is a chance to improve existing biology with synthetic(人造的)biology.”

Erb’s team identified 17 enzymes(酶)from nine different organisms, re-engineering three of them, which had enlarged carbon consumption. When those enzymes worked together as a team, they worked better at not only plants’ natural enzymes, but also themselves individually.

Existing enzymes in plants consume about 5 to 10 molecules(分子)of carbon dioxide per second. The team of enzymes that Erb used consumed 80 molecules per second.

So far, these enzymes have only been tested in test tubes in the lab, but the next step is real world testing where the enzymes would be introduced into plants to see if the same result occurs. If those tests show that plants really can be supercharged, we will have a new tool in the fight against climate change where not only do we protect the amazing carbon-absorbing forests we have, but we also apply these super plants or an artificial leaf technology using the enzymes into other fields.

【小题1】Why can't forests and oceans balance nature nowadays?
A.Oceans and forests are getting smaller.
B.We human beings give off too much carbon dioxide.
C.A large number of forests are cut down.
D.There are too many creatures in the world.
【小题2】Which is the key defense against climate change according to Erb and his team?
A.To increase the plants' ability and efficiency to absorb carbon dioxide.
B.To make oceans and forests absorb more carbon dioxide quickly.
C.To reduce humans' activities giving off too much carbon dioxide.
D.To increase the number of plants in the world.
【小题3】What can we conclude from the last paragraph?
A.The enzymes have proved useful in the real world.
B.Erb’s team are confident about the technology.
C.The enzymes only work in the lab.
D.The technology may have a bright future.
【小题4】This passage is intended to ____.
A.introduce a possible way to better plants’ ability to absorb carbon dioxide
B.call on people to pay more attention to the balance of nature
C.analyze the cause and result of climate change related to plants
D.explore the possibility of using plants to fight against climate change

同类题4

   Onions make you cry, add flavor to food and win popularity for their medicinal benefits. Now the vegetable has another use—_____ green energy.

Anew system debuts(首次亮相)on Friday that _____ onion juice into electricity at Gills Onions, the largest fresh onion processor in the United States.

The Oxnard, California-based company _____ its new onion-fueled power to reduce its electric bill by $700,000 a year and _____ its annual greenhouse gas emissions by up to 30,000 tons.

The _____ ending to this green energy tale, however, started with another question: how to _____ onion waste.

“_____ we peel an onion, 35 to 40 percent of the onion comes off before we have a(n)_____ onion. That's the top, tail and skin around the onion, and _____ we can get to the meat,” said Steven Gill, co-owner of the 25-year-old company.

They used to pull the waste to the fields for compost(混合肥料), but that turned out to be a tough ______. Ten years ago, Gill started looking at technology for a(n) _____, including microturbines(微型燃气轮机).

“We ______ cutting the skins into pieces and extracting all the ______, which is very high in sugars, and bacteria love that stuff,” Gill said.

In the new system, bacteria ______ methane(甲烷)gas from the juice. The gas then goes to two 300 kilowatt fuel cells, creating ______ power for 460 homes. If everything goes smoothly, ______ are that the company will get 35 to 40 percent of its electricity from the on-site generator.

The company ______ $ 9. 5 million in the project and will receive $2. 7 million from Southern California Gas Co. _____ cutting its electric bill, the company will save $400,000 in costs and expects paybacks in the new future.

The onion grower now has a new ______: to be a zero-waste facility in the coming decade.

“We want to ______ it all the way through and make the full circle,” Gill said.

【小题1】
A.storingB.conveyingC.generatingD.pushing
【小题2】
A.changesB.transportsC.movesD.throws
【小题3】
A.urgesB.expectsC.assumesD.promises
【小题4】
A.controlB.removeC.checkD.cut
【小题5】
A.satisfyingB.disappointingC.suitableD.stable
【小题6】
A.take care ofB.look out forC.get rid ofD.give way to
【小题7】
A.WhenB.UnlessC.OnceD.Until
【小题8】
A.deliciousB.practicalC.accessibleD.usable
【小题9】
A.eventuallyB.luckilyC.probablyD.suddenly
【小题10】
A.problemB.decisionC.situationD.mistake
【小题11】
A.excuseB.agreementC.solutionD.judgment
【小题12】
A.end upB.hold outC.set outD.take up
【小题13】
A.tailsB.skinsC.gasD.juice
【小题14】
A.protectB.produceC.preventD.introduce
【小题15】
A.muchB.moreC.enoughD.too
【小题16】
A.challengesB.chancesC.guessesD.things
【小题17】
A.appliedB.distributedC.investedD.attracted
【小题18】
A.In terms ofB.In response toC.In exchange forD.In addition to
【小题19】
A.worryB.achievementC.adventureD.goal
【小题20】
A.observeB.followC.getD.put

同类题5

   Leon,12,was born without fingers on his left hand. That didn't stop him from being able to do many tasks. But Leon could not grasp more than one object at a time. So Leon's father,Paul,created a prosthesis(义肢),using a3-D printer. Now Leon has fingers that can open and close. "It was a do-it-yourself,father and son adventure," says Paul.

When Leon was a baby,his doctor advised his parents not to give him a prosthetic hand until he was in his early teens. "The doctor said Leon should first learn to get full use of the hand he was born with,"says Paul. As Leon got older,his father considered buying a prosthetic hand,which can cost as much as $30,000. Then Paul found a more affordable solution.

One day,Paul discovered a video on the Internet about Robohand,a prosthesis created by a 3--D printer. He downloaded the free instructions and called Robohand's creators for advice. They told him all he needed was a 3-D printer-which costs around $2,000 and some materials.

Luckily,Leon's school had recently bought a 3-D printer and it offered to help Paul build the hand for Leon. "We used a soccer shin pad(护胫),cardboard,and tape. They cost about $10,"says Paul.

With his new hand,Leon can do things better. "I can help my mom more,because now I can carry two grocery bags,"he says.

Leon's father has already built several hands for Leon. Leon helps design each one. He says there's one thing in particular that he wants to do with a future prosthesis. "The goal,"he tells the reporter from the local evening paper,"is to be able to tie my shoelaces(鞋带)".

【小题1】Why did Leon's doctor disapprove of his using a prosthesis in his childhood?
A.The prosthetic technology was underdeveloped then.
B.A prosthesis was very expensive at that time.
C.To learn to use the disabled hand was important.
D.The original hand could do many tasks.
【小题2】Leon's father managed to get Leon a new hand by _________.
A.collecting money on the Internet
B.buying a prosthetic hand
C.buying a 3-D printer
D.printing a hand
【小题3】The materials used for Leon's hand can be described as _______.
A.cheap and common
B.strange and valuable
C.personal and lovely
D.basic and solid
【小题4】What is the best title for the passage?
A.A DIY EnthusiastB.A Helping Hand
C.A Great AdventureD.A Lucky Escape