题干

   Chinese scientists recently have produced two monkeys with the same gene, Zhong Zhong and Hua Hua, using the same technique that gave us Dolly the sheep. These monkeys are not actually the first primates(灵长类)to be cloned. Another one named Tetra was produced in the late 1990s by embryo(胚胎)splitting, the division of an early-stage embryo into two or four separate cells to make clones. By contrast, they were each made by replacing an egg cell nucleus(原子核)with DNA from a differentiated body cell. This Dolly method, known as somatic cell nuclear transfer(SCNT), can create more clones and allows researchers greater control over the edits they make to the DNA.

Success came from adopting several new techniques. These included a new type of microscopy to better view the cells during handling or using several materials that encourage cell reprogramming, which hadn’t been tried before on primates. Still, the research process proved difficult, and many attempts by the team failed. Just two healthy baby monkeys born from more than 60 tested mothers. This leads to many researchers’ pouring water on the idea that the team’s results bring scientists closer to cloning humans. They thought this work is not a stepping stone to establishing methods for obtaining live born human clones. Instead, this clearly remains a very foolish thing to attempt, it would be far too inefficient, far too unsafe, and it is also pointless.

But the scientists involved emphasize that this is not their goal. There is now no barrier for cloning primate species, thus cloning humans is closer to reality. However, their research purpose is entirely for producing non-human primate models for human diseases; they absolutely have no intention, and society will not permit this work to be extended to humans. Despite limitations, they treat this breakthrough a novel model system for scientists studying human biology and disease.

【小题1】What do we know about the technology called SCNT?
A.It created the first two primates.
A.It may contribute to editing the DNA.
B.It can divide an early-stage embryo into several cells.
C.It produced two cloned monkeys with different genes.
【小题2】What does the author mean by “pouring water on the idea” in paragraph 2?
A.Keeping a hot topic of it.
B.Attaching no importance to it.
C.Having a low opinion of it.
D.Adding supportive evidence to it.
【小题3】What is the scientists’ purpose to clone these monkeys?
A.To prepare for their research on human cloning.
B.To serve as a stepping stone to their reputation.
C.To help with the study of human diseases.
D.To raise money for holding an exhibition of novels.
【小题4】What can we infer from the passage?
A.Cloning humans is already on its way.
B.New techniques seem to be pointless.
C.Society won’t agree to clone another monkey.
D.The success rate of cloning a monkey was not high.
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同类题2

   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3

   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

同类题4

   You'll probably never go to Mars or sing on the stage with The Rolling Stones. But if virtual reality (VR)ever lives up to its promise, you might be able to do all these things - and many more - without even leaving your home.Unlike real reality, virtual reality means simulating(模拟)bits of our world. Apart from games and entertainment, it's long been used for training airline pilots and surgeons and for helping scientists to figure out difficult problems such as the structure of protein molecules(蛋白质分子). Then how does it work?

Close your eyes and think of virtual reality and you probably picture something like this:a man wearing a wrap-around headset and data gloves wired into a powerful workstation or supercomputer. What distinguishes VR from an ordinary computer experiences the nature of the input and output. While an ordinary computer uses things like a keyboard, a mouse, or speech recognition for input, VR uses sensors that detect how your body is moving. A PC displays output on a screen while VR uses two screens (one for each eye) , surround-sound speakers, and maybe some forms of touch and body feedback as well.

VR has been routinely used by scientists,doctors, engineers, architects, archaeologists, and the military for about the last 30 years. Difficult and dangerous jobs are hard to train for. How  can you safely practice taking a trip to space, making a parachute jump, or carrying out brain surgery? All these things are obvious candidates for virtual reality applications.

Like any technology, virtual reality has both good and bad points. Critics always raise the risk that people may be addicted to alternative realities to the point of ignoring their real-world lives, but this criticism has been leveled at everything from radio and TV to computer games and the Internet. Like many technologies, VR takes little or nothing away from the real world: you don't have to use it if you don't want to.

【小题1】According to the passage, virtual reality means ____________ .
A.imagining beautiful things in our mind
B.creating something that doesn't exist
C.creating an environment that seems real
D.cloning something that has died out
【小题2】What equipment do we probably need for virtual reality?
A.A keyboard, a headset and a supercomputer.
B.A headset, data gloves and speech recognition.
C.A headset, data gloves and a supercomputer.
D.A keyboard, a mouse and speech recognition.
【小题3】Paragraph 3 is mainly about ____________ .
A.the principles of virtual reality
B.the applications of virtual reality
C.the history of virtual reality
D.the study team of virtual reality
【小题4】What is the writer's attitude towards VR?
A.Appreciative.B.Cautious.
C.Skeptical.D.Indifferent.

同类题5

   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 Bhatti, 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】How will the Norwegian autonomous ship be developed?
A.On the basis of Rolls-Royce.
B.By a single company independently.
C.By two native companies working together.
D.By taking electrical technology from Australia.
【小题3】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4】What would be the best title for the text?
A.Automation under SailB.Self-sailing Ships in Use
C.Automation in Some FieldsD.Automation in Imagination