One step too farScientists have been trying t...

One step too far

Scientists have been trying to figure out how to alter the genes of humans for many years now, and it looks like they've finally cracked (破解) the code. But while this may seem like a great step forward in science, some also believe that it's one step back when it comes to ethics.

In August, a group of scientists from the US and South Korea worked together to successfully edit a human embryo and remove a genetic mutation (突变) that would have led to heart disease, reported The Guardian.

This was achieved with the help of CRISPR, a gene-editing tool that allows scientists to “cut and paste” human DNA.

Although this was the first example of an embryo's genes being changed successfully, the benefits of gene editing have already been tested in living patients.

In 2015, a five-month-old girl from the UK was saved after doctors used edited cells to fight off her cancer. As of today, she's alive and well.

And in the US last year, scientists managed to remove HIV cells from several patients by editing the genes inside their bodies.

Some people hope that in the future, diseases or birth detects could simply be “edited out”. However, others believe this could lead to so-called designer babies, giving parents the option to choose everything from eye color to intelligence.

“You could find wealthy parents buying the latest ‘upgrades’ for their children, leading to even greater inequality than we already live with,” Marcy Darnovsky, director of the San Francisco Center for Genetics, told BBC News.

In spite of these ethical concerns, experts say it’s not possible to create the “perfect” human being. Despite the progress scientists have made, we don’t understand human genes enough to give all unborn child great brainpower or amazing singing abilities.

“Right now, we know nothing about genetic enhancement,” Hank Greely, a director of sciences at Stanford University, US, told The New York Times. “We’re never going to be able to say, honestly, ‘This embryo looks like it would score high on the two-part SAT.’”

So it looks like if we want good exam results, or to impress people with our piano skills, we’ll have to stick with the old fashioned method of plain hard work — at least for now.

1.The underlined word “alter” in Paragraph 1 probably means ______.

A.record

B.change

C.remove

D.increase

2.Why do some people consider human gene editing a step backwards？ ______

A.They don't think it is an effective way to light diseases.

B.They are concerned that it could lead to genetic mutations.

C.They think it could lead to designer babies and increased inequality.

D.They worry that it could make parents abandon children with birth defects.

3.What was the first successful example of human embryo gene editing？ ______

A.A genetic mutation related to heart disease was removed by scientists

B.A newborn baby with cancer was saved by edited cells.

C.HIV cells were removed from patients’ bodies.

D.Some birth defects were simply edited out.

4.What can we conclude from the text？ ______

A.Gene editing is regarded as the perfect way to treat birth defects.

B.There is still a long way to go to fully understand human genes.

C.Gene editing could help enhance human intelligence in the near future.

D.Scientists are pessimistic about the future of gene editing.

高三英语阅读理解困难题查看答案及解析

For many days I have been trying to　 what it is that makes Jack so annoyed.

A. carry out B. figure out

C. watch out D. stand out

高三英语单项填空中等难度题查看答案及解析

I could have helped him out, to tell the truth, I _____ too busy.

高三英语单项填空中等难度题查看答案及解析

72. For many days I have been trying to ______ what it is that makes Jack so angry.

高三英语单项填空简单题查看答案及解析

When you were trying to figure out what to buy for the environmentalist on your holiday list, fur probably didn’t cross your mind. But some ecologists and fashion (时装)enthusiasts are trying to bring back the market for fur made from nutria(海狸鼠).

Unusual fashion shows in New Orleans and Brooklyn have(showcased)nutria fur made into clothes in different styles. “It sounds crazy to talk about guilt-free fur-unless you understand that the nutria are destroying vast wetlands every year”, says Cree McCree, project director of Righteous Fur.

Scientists in Louisiana were so concerned that they decided to pay hunters $5 a tail. Some of the fur ends up in the fashion shows like the one in Brooklyn last month.

Nutria were brought there from Argentina by fur farmers and let go into the wild. “The ecosystem down there can’t handle this non-native species(物种).It’s destroying the environment. It’s them or us.” says Michael Massimi, an expert in this field.

The fur trade kept nutria check for decades，but when the market for nutria collapsed in the late 1980s，the cat-sized animals multiplied like crazy.

Biologist Edmond Mouton runs the nutria control program for Louisiana. He says it’s not easy to convince people that nutria fur is green, but he has no doubt about it. Hunters bring in more than 300,000 nutria tails a year, so part of Mouton’s job these days is trying to promote fur.

Then there’s Righteous Fur and its unusual fashion. Model Paige Morgan says，”To give people a guilt-free option that they can wear without someone throwing paint on them-1 think that’s going to be a massive thing, at least here in New York.” Designer Jennifer Anderson admits it took her a while to come around to the opinion that using nutria fur for her creations is morally acceptable. She trying to come up with a lable to attach to nutria fashions to show it is eco-friendly.

1.What is the purpose of the fashion shows in New Orleans and Brooklyn?

A.To promote guilt-free fur.

B.To expand the fashion market.

C.To introduce a new brand.

D.To celebrate a winter holiday.

2.Why are scientists concerned about nutria?

A.Nutria damage the ecosystem seriously.

B.Nutria are an endangered species.

C.Nutria hurt local cat-sized animals.

D.Nutria are illegally hunted.

3.What does the underlined word “collapsed” in paragraph 5 probably mean?

A.Boomed. B.Became mature. C.Remained stable. D.Crashed.

4.What can we infer abouf wearing fur in New York according to Morgan?

A.It’s formal. B.It’s risky. C.It’s harmful. D.It’s traditional.

高三英语阅读理解困难题查看答案及解析

When choosing a product, I sometimes try to figure out the meaning___ to its brand name.

A．attaching          B．having attached     C．to attach          D．attached

高三英语单项填空中等难度题查看答案及解析

A lot of teams wanted me to ____ for other positions and I told them no.

A．try out            B．figure out         C．let out            D．break out

高三英语单项填空中等难度题查看答案及解析

The manager of the travel agency was trying hard to figure out how he would attract more customers _____ an extraordinary idea _____  his mind and he immediately knew what to do.

高三英语单项填空中等难度题查看答案及解析

There seems to be two causes as I try to figure out __________ that prevents so many children from being as happy as before.

A. how it is　　　　　　　　　　 B. when it is

C. what it is　　　　　　　　　 D. why it is

高三英语单项填空中等难度题查看答案及解析

Dogs may not know exactly what you are doing especially when you’re trying to figure out a square root or diagram a sentence. But according to a new study, dogs can understand what we’re thinking and feeling by reading our facial expressions and body language and following our eyes.

Researchers studied 29 dogs. The dogs were shown a movie where a woman looked directly at them and said “Hi dog!” Then, the woman looked at a flowerpot sitting next to her. The researchers found that when the woman looked at and spoke directly to a dog, the dog usually followed her eyes to the flowerpot. It proved that the dogs knew that the woman was thinking about the flowerpot.

“By following the eye movements of dogs, we were able to get a first-hand look at how their minds are actually working,” said Jozsef, the senior researcher.

Later in the movie, the woman said “Hi dogs” in a low voice and didn’t look at the dog before looking at the flowerpot. In that situation, the dogs didn’t seem to understand what the woman was thinking. There was no eye contact, and the woman didn’t appear to speak to the dogs directly.

That comes as no surprise to dog trainer Jones. “Dogs normally speak through nonverbal signals. It’s more natural to them,” she said. “If you’ve ever watched dogs at a dog park, you’ve seen it. Within 30 seconds they enter the park, much information has passed between the new dog and the ones already in the park. They’re exchanging looks, observing eyes and body posture. On the other hand, when you speak to a dog, they are learning a foreign language.”

Picking up your nonverbal signals seems more natural. So, if you were hoping that all this means your dog could help you solve your math problems, you’re probably out of luck. But he or she might be a lot more in tune with what you’re thinking than you previously thought.

1.How could the researchers find that the dogs understood the woman’s intention?

2.According to the text, Jones finds that ______.

3.It is implied in the text that dogs can read your emotions only if ______.

4.What does the underlined phrase “be in tune with” in the last paragraph mean?

高三英语阅读理解中等难度题查看答案及解析