Plastic-Eating Worms
Humans produce more than 300 million tons of plastic every year. Almost half of that winds up in landfills(垃圾填埋场),and up to 12 million tons pollute the oceans. qSo far there is no effective way to get rid of it, but a new study suggests an answer may lie in the stomachs of some hungry worms.
Researchers in Spain and England recently found that the worms of the greater wax moth can break down polyethylene, which accounts for 40% of plastics. The team left 100 wax worms on a commercial polyethylene shopping bag for 12 hours, and the worms consumed and broke down about 92 milligrams, or almost 3% of it. To confirm that the worms' chewing alone was not responsible for the polyethylene breakdown, the researchers made some worms into paste(糊状物) and applied it to plastic films. 14 hours later the films had lost 13% of their mass--apparently broken down by enzymes(酶)from the worms' stomachs. Their findings were published in Current Biology in 2017.
Federica Bertocchini, co-author of the study, says the worms' ability to break down their everyday food-beeswax--also allows them to break down plastic "Wax is a complex mixture, but the basic bond in polyethylene, the carbon-carbon bond, is there as well, "she explains. "The wax worm evolved a method or system to break this bond. "
Jennifer Debruyn, a microbiologist at the University of Tennessee, who was not involved in the study, says it is not surprising that such worms can break down polyethylene. But compared with previous studies, she finds the speed of breaking down in this one exciting. The next step, DeBruyn says, will be to identify the cause of the breakdown. Is it an enzyme produced by the worm itself or by its gut microbes(肠道微生物)?
Bertocchini agrees and hopes her team’s findings might one day help employ the enzyme to break down plastics in landfills. But she expects using the chemical in some kind of industrial process-not simply "millions of worms thrown on top of the plastic.”
1.What can we learn about the worms in the study?
A. They take plastics as their everyday food.
B. They are newly evolved creatures.
C. They can consume plastics.
D. They wind up in landfills.
2.According to Jennifer DeBruyn, the next step of the study is to .
A. identify other means of the breakdown
B. find out the source of the enzyme
C. confirm the research findings
D. increase the breakdown speed
3.It can be inferred from the last paragraph that the chemical might .
A. help to raise worms
B. help make plastic bags
C. be used to clean the oceans
D. be produced in factories in future
高二英语阅读理解中等难度题
Plastic-Eating Worms
Humans produce more than 300 million tons of plastic every year. Almost half of that winds up in landfills(垃圾填埋场), and up to 12 million tons pollute the oceans. So far there is no effective way to get rid of it, but a new study suggests an answer may lie in the stomachs of some hungry worms.
Researchers in Spain and England recently found that the worms of the greater wax moth can break down polyethylene, which accounts for 40% of plastics. The team left 100 wax worms on a commercial polyethylene shopping bag for 12 hours, and the worms consumed and broke down about 92 milligrams, or almost 3% of it. To confirm that the worms’ chewing alone was not responsible for the polyethylene breakdown, the researchers made some worms into paste(糊状物) and applied it to plastic films. 14 hours later the films had lost 13% of their mass — apparently broken down by enzymes (酶) from the worms’ stomachs. Their findings were published in Current Biology in 2017.
Federica Bertocchini, co-author of the study, says the worms’ ability to break down their everyday food — beeswax — also allows them to break down plastic. "Wax is a complex mixture, but the basic bond in polyethylene, the carbon-carbon bond, is there as well, "she explains, "The wax worm evolved a method or system to break this bond. "
Jennifer DeBruyn, a microbiologist at the University of Tennessee, who was not involved in the study, says it is not surprising that such worms can break down polyethylene. But compared with previous studies, she finds the speed of breaking down in this one exciting. The next step, DeBruyn says, will be to identify the cause of the breakdown. Is it an enzyme produced by the worm itself or by its gut microbes(肠道微生物)?
Bertocchini agrees and hopes her team’s findings might one day help employ the enzyme to break down plastics in landfills. But she expects using the chemical in some kind of industrial process — not simply "millions of worms thrown on top of the plastic."
1.What can we learn about the worms in the study?
A. They take plastics as their everyday food.
B. They are newly evolved creatures.
C. They can consume plastics.
D. They wind up in landfills.
2.According to Jennifer DeBruyn, the next step of the study is to .
A. identify other means of the breakdown
B. find out the source of the enzyme
C. confirm the research findings
D. increase the breakdown speed
3.It can be inferred from the last paragraph that the chemical might .
A. help to raise worms
B. help make plastic bags
C. be used to clean the oceans
D. be produced in factories in future
4.What is the main purpose of the passage?
A. To explain a study method on worms.
B. To introduce the diet of a special worm.
C. To present a way to break down plastics.
D. To propose new means to keep eco-balance.
高二英语阅读理解困难题查看答案及解析
Plastic-Eating Worms
Humans produce more than 300 million tons of plastic every year. Almost half of that winds up in landfills(垃圾填埋场),and up to 12 million tons pollute the oceans. qSo far there is no effective way to get rid of it, but a new study suggests an answer may lie in the stomachs of some hungry worms.
Researchers in Spain and England recently found that the worms of the greater wax moth can break down polyethylene, which accounts for 40% of plastics. The team left 100 wax worms on a commercial polyethylene shopping bag for 12 hours, and the worms consumed and broke down about 92 milligrams, or almost 3% of it. To confirm that the worms' chewing alone was not responsible for the polyethylene breakdown, the researchers made some worms into paste(糊状物) and applied it to plastic films. 14 hours later the films had lost 13% of their mass--apparently broken down by enzymes(酶)from the worms' stomachs. Their findings were published in Current Biology in 2017.
Federica Bertocchini, co-author of the study, says the worms' ability to break down their everyday food-beeswax--also allows them to break down plastic "Wax is a complex mixture, but the basic bond in polyethylene, the carbon-carbon bond, is there as well, "she explains. "The wax worm evolved a method or system to break this bond. "
Jennifer Debruyn, a microbiologist at the University of Tennessee, who was not involved in the study, says it is not surprising that such worms can break down polyethylene. But compared with previous studies, she finds the speed of breaking down in this one exciting. The next step, DeBruyn says, will be to identify the cause of the breakdown. Is it an enzyme produced by the worm itself or by its gut microbes(肠道微生物)?
Bertocchini agrees and hopes her team’s findings might one day help employ the enzyme to break down plastics in landfills. But she expects using the chemical in some kind of industrial process-not simply "millions of worms thrown on top of the plastic.”
1.What can we learn about the worms in the study?
A. They take plastics as their everyday food.
B. They are newly evolved creatures.
C. They can consume plastics.
D. They wind up in landfills.
2.According to Jennifer DeBruyn, the next step of the study is to .
A. identify other means of the breakdown
B. find out the source of the enzyme
C. confirm the research findings
D. increase the breakdown speed
3.It can be inferred from the last paragraph that the chemical might .
A. help to raise worms
B. help make plastic bags
C. be used to clean the oceans
D. be produced in factories in future
高二英语阅读理解中等难度题查看答案及解析
The world’s population is more mobile (移动的)today than ever before. In 2010, more than 200 million people left their home countries to live in a new country. This is about 3 percent of the total world population. Some experts believe that number will swell to 400 million by 2050. Rates of immigration have remained strong for the last 300 years, but patterns of immigration have changed since World War II. The backgrounds and experiences of today’s immigrants are different from those of the typical European immigrant of the nineteenth and early twentieth centuries. Contemporary immigrants range from unskilled laborers to highly skilled professionals, and they come from and go to countries all over the world.
In the nineteenth century and until World War II, immigration was primarily in one direction- from the Old World to the New World. This is no longer the case. Countries such as Russia and China, which have long been, and continue to be, significant source countries, are now also destination countries. There is also considerable mobility inside regions, such as from one European country to another, or among the countries of the former Soviet Union.
In spite of such differences, the push and pull factors for immigration remain essentially the same as they were 100 years ago. Most people move to another country because they want a better life. For the majority of immigrants, this means better economic conditions. As in past generations, a labor shortage in one country often draws workers from another country, especially if wages are significantly higher. In some small countries, for example, Qatar, United Arab Emirates, and Kuwait, there are more jobs than citizens. The demand for labor is so high that the majority of the population consists of foreign-born workers, ranging from highly skilled engineers and financial experts to domestic and construction workers.
In traditional destination countries, such as the United States, however, labor needs have changed. Today, although there is still demand for unskilled labor, there is increasing demand for people with a high level of skill and education. The need for less skilled labor has shifted to other countries. As work on farms and in industry in the United States and Canada once drew workers from all over the world, now work in factories in Taiwan and south Korea attracts workers from Vietnam, the Philippines, and Cambodia.
Most global immigration is legal: however, a large number of people also move across national borders illegally in pursuit of employment. Experts estimate that about 15 to 20 percent of immigrants worldwide are in their new countries illegally. The United States has the largest number of these immigrants, followed by South Africa, with significant numbers also in Northern and Western Europe and Mexico. These immigrants face particular challenges because they often must hide from the authorities who might deport them back to their home countries. Their illegal status also means that employers may take advantage of them by forcing them to work longer hours and paying them less than the legal minimum wage.
Although economics remains the most important motivation in all forms of immigrant, other factors are also important. Some people decide to leave their home countries because their actions or political beliefs make it dangerous for them to remain. Others choose to leave because their home country has become too dangerous and unstable, often because of war or political unrest. They wish to find a place that is secure for themselves and their families. Education is also a significant factor for many modern immigrants. They want to raise their children in a place where they can get a good education, which, in turn, they hope will provide them with better prospects for the future. Finally, family and community ties also play a role in immigration decisions. As in the past, once a group of people from one country establishes a community in a new country, more people from that country is likely to follow.
The pattern, direction, and rate of immigration may change as the global economy changes. However, as long as life in a new country is more attractive than life in the old country, immigration will continue.
1.According to the reading, what are the patterns of immigration in China and Russia today?
A. Many people leave these countries while many people also immigrate to them.
B. They are major source countries for immigration.
C. They are major destination countries for immigrants.
D. Some people immigrate to these countries but many more people leave them.
2.Why is the percentage of foreign-born workers so high in Kuwait, Qatar, and the United Arab Emirates?
A. These countries pay very high wages, so they attract many foreign workers.
B. There are not enough native-born workers in these countries so they must recruit workers from other countries.
C. It is very easy to immigrate to these countries.
D. These countries are very stable so many workers prefer to go there.
3.Why do some employers sometimes pay illegal immigrants less than the legal minimum wage?
A. Employers know that they will not complain about their wages to authorities.
B.They often do not speak good English.
C. Authorities might send illegal immigrants back to their home country.
D. Illegal workers often cause problems for employers.
4.Which is not the factor contributing to the immigration?
A. Education
B. Political instability
C. Religious freedom
D. Family and community connections
高二英语阅读理解中等难度题查看答案及解析
Although the United States covers so much land and the land produces far more food than the present population needs,its people are by now almost entirely an urban society. Less than a tenth of the people are engaged in agriculture and forestry(林业), and most of the rest live in or around towns,small and large.Here the traditional picture is changing: every small town may still be very like other small towns,and the typical small town may represent a widely accepted view of the country,but most Americans do not live in small towns any more. Half the population now lives in some thirty metropolitan areas(1arge cities with their suburbs, of more than a million people each—a larger proportion than in Germany or England,let alone France). The statistics(统计)of urban and rural population should be treated with caution because so many people who live in areas classified as rural travel by car to work in a nearby town each day. As the rush to live out of town continues,rural areas within reach of towns are gradually filled with houses, so that it is hard to say at what moment a piece of country becomes a suburb. But more and more the typical American lives in a metropolitan rather than a small town environment.
1.If now America has 250 million people.how many of them are engaged in agriculture and forestry?
A.About 25 million |
B.More than 25 million |
C.Less than 25 million |
D.Less than 225 million |
2.Which of the following four countries has the smallest proportion of people living in metropolitan areas?
A.United States | B.Germany | C.France | D.England |
3.What’s the meaning of the word“metropolitan”in the middle of the passage?
A.Of a large city with its suburbs | B.Of small and large towns |
C.Of urban areas | D.Of rural areas |
高二英语阅读理解中等难度题查看答案及解析
Read More &Spend Less
We have more than 7 million used books for sale, from the earliest board books to the all-time classics, if you like what we have to offer, Tell-a-Friend and we’ll give you more reasons to read!
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Giraffes Can’t Dance
by Giles Andreae
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2004, Paperback
ISBN:9780439539470
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Laugh-Out-Loud Jokes for Kids
By Rob Elliott
With over 700,000 copies sold, this book will have children rolling on the floor with laughter. A great gift idea for any child.
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Love You Forever
by Robert Munsch
With simple text and pictures, Love You Forever is a book to be shared---a story about love that children will carry with them throughout their lives.
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How to Win Friends &Influence People
by Dale Carnegie
As the most famous confidence-building book ever published, this classic book will turn your relationships around and improve your relationships with everyone in your life.
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ISBN: 9788087888223
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1.The “Tell-a-Friend” program encourages people to .
A. share the website with others
B. help a friend form the habit of reading
C. take pleasure in reading with their friends
D. read more but spend less
2.Who wrote the story about animals?
A. Rob Elliott B. Dale Carnegie
C. Giles Andreae D. Robert Munsch
3.Which book has a different kind of paper cover from the others?
A. How to Win Friends& Influence People
B. Love You Forever
C. Giraffes Can’t Dance
D. Laugh-Out-Loud Jokes for Kids
高二英语阅读理解中等难度题查看答案及解析
Read More &Spend Less
We have more than 7 million used books for sale, from the earliest board books to the all-time classics, if you like what we have to offer, Tell-a-Friend and we’ll give you more reasons to read!
Any member of our website who invites friends and family to try our books using the “Tell-a Friend” program will see a 20% discount (折扣) when that friend places their first order within 14 days.
Start exploring and save big on all your favorites. Here we list some of our books that are heavily discounted.
Giraffes Can’t Dance
by Giles Andreae
This book has been pleasing children for over 15 years. Gerald the tall giraffe would love to join in with the other animals at the Jungle Dance, but everyone knows that giraffes can’t dance….or can they?
2004, Paperback
ISBN:9780439539470
From $0.99
Laugh-Out-Loud Jokes for Kids
By Rob Elliott
With over 700,000 copies sold, this book will have children rolling on the floor with laughter. A great gift idea for any child.
2010, Paperback
ISBN:9780800788032
From $0.89
Love You Forever
by Robert Munsch
With simple text and pictures, Love You Forever is a book to be shared---a story about love that children will carry with them throughout their lives.
1995, Hardback
ISBN:9780099266891
From $ 1.98
How to Win Friends &Influence People
by Dale Carnegie
As the most famous confidence-building book ever published, this classic book will turn your relationships around and improve your relationships with everyone in your life.
2013, Paperback
ISBN: 9788087888223
From $0.99
1.The “Tell-a-Friend” program encourages people to .
A. take pleasure in reading with their friends
B. help a friend form the habit of reading
C. share the website with others
D. read more but spend less
2.Who wrote the story about animals?
A. Rob Elliott B. Giles Andreae
C. Dale Carnegie D. Robert Munsch
3.Which book has a different kind of paper cover from the others?
A. How to Win Friends& Influence People
B. Laugh-Out-Loud Jokes for Kids.
C. Giraffes Can’t Dance
D. Love You Forever
高二英语听力第三部分中等难度题查看答案及解析
I am_____ to learn that Picasso produced more than 20,000 pieces of art ___ he wasn’t just a painter.
A.amazing ; and that | B.amazed ; that |
C.amazed ; and that | D.amazing; and |
高二英语单项填空简单题查看答案及解析
Mental health experts estimate that depression affects more than 120 million people worldwide. It severely affects the person’s quality of life and, in extreme cases, can lead to people killing themselves. Anti-depressant medicines have been shown as an effective treatment for most patients. But the drugs are unable to help a small number of people with the disorder.
For such person, doctors may suggest deep transcranial magnetic stimulation(经颅磁力刺激), or DTMS for short. In this treatment, patients wear a special helmet connected to a machine. An electric coil(线圈)in the helmet sends out regular waves of electromagnetic energy. These beating sounds produce changes in the brain area responsible for the disorder.
Electromagnetic stimulation(刺激) was first tried to treat depression over 30 years ago. Now, a new generation of wiring can direct the energy on one part of the brain. DTMS starts with daily 20-mimute-long treatments for 20 to 30 days. The patient then returns for treatment two to three times a week for several weeks.
The only side effect is sometimes slight head pain. Aaron Tendler is the chief medical officer of Brains way, the company that makes the machine. He said that it’s hard to say how long the effects of DTMS last.
DTMS is being used in Europe to treat both depression and other conditions. Patients there are getting treated for dementia, Alzheimer’s and Parkinson’s disease. And DTMS is even being used to help some Europeans give up smoking.
But in the United States, the Federal Food and Drug Administration(FFDA) has approved it only for the treatment of depression which cannot be treated by medicine. But clinical tests are continuing on other conditions, such as obsessive-compulsive disorder and post-traumatic stress disorder. Both of the disorders, like depression, can get in the way of a person working and getting along with people.
1.Why are people concerned about depression?
A.Because it may lead to death sometimes.
B.Because only a few people can recover from it.
C.Because it does not affect social communication.
D.Because medicine treatment usually fails to work on it.
2.How does DTMS help patients with depression?
A.By wearing a helmet in daily life.
B.By performing an operation on the head.
C.By making them face the disease bravely.
D.By letting electromagnetic waves stimulate the brain.
3.What can we infer about DTMS from the text?
A.It is quite safe to use it worldwide.
B.The use of it in America is forbidden.
C.It can cure patients of depression in a month.
D.It will be widely used in treating more diseases.
4.What would be the best title for the text?
A.Finding Hope in A Hopeless Depression
B.DTMS - A New Treatment for Depression
C.The Killer of Modern Humans Depression
D.Using Electromagnetic Waves to Cure Depression
高二英语阅读理解中等难度题查看答案及解析
Scientists have recently discovered a major habitat where live more than 1.5 million Adelie penguins(企鹅)near the Antarctic Peninsula. Based on direct ground counts and computer counts, the researchers found a total of 751,527 pairs of Adelie penguins on the Danger Islands in the Weddell Sea on the east side of the Antarctic Peninsula. The Adelie penguins discovered here is more than the rest in the other places of Antarctic Peninsula, which was published in the journal Scientific Reports.
Moreover, the number represents the first complete census of Adelie penguins in the Danger Islands, the researchers added. “Until recently, the Danger Islands wasn't known to be an important penguin habitat.” Heather Lynch, an ecologist from Stony Brook University who led the study, said, “These super habitats have gone undiscovered for decades partly because the islands themselves are distant and the dangerous waters that surround them.” The Danger Islands appears to have avoided recent loss in penguin population documented on other parts of the Antarctic Peninsula.
Another study published earlier suggested that more than 70 percent of king penguins may disappear by the end of the century as a result of global warming and overfishing. As the Danger Islands is likely to remain important islands for many penguins under climate change, scientists believe it deserves special consideration in the design of Marine Protected Areas in this area. “Now that we know how important this area is for penguin, we can better move forward designing Marine Protected Areas and managing the fishery,” said Lynch.
The idea of building the Marine Protected Areas, which covers 1.8 million square km of the Weddell Sea and around the Antarctic Peninsula, was first put forward by the European Union and supported by nongovernmental organization Greenpeace. In January, a global campaign has been started in the vast fishing-free zone to better protect wildlife.
1.What can we learn from paragraph 1?
A. Researchers knew the number of penguins only by computers.
B. There are 751,527 pairs of penguins on the Antarctic Peninsula.
C. Researcher may have never been to the Antarctic Peninsula.
D. The Danger Islands may be fit for penguins to live on.
2.What does the underlined word “census” in paragraph 2 mean?
A. Population count. B. Living condition.
C. Birth. D. Desert.
3.Why are there many penguins on the Danger Islands?
A. The Danger Islands is unknown for humans.
B. There is little climate change there.
C. Many people are protecting penguins.
D. The Danger Islands is free from being disturbed by humans.
4.What can we know from what Lynch said?
A. Half of king penguins will die out in the future.
B. The Antarctic Peninsula needn't become Protected Areas.
C. Because the Danger Islands is dangerous, it becomes a super habitat.
D. The number of penguins discovered here is the largest in the Antarctic Peninsula.
高二英语阅读理解简单题查看答案及解析
Washington, April 4----- The United States has more than 90 million families for the first time, but each contains fewer people on average than ever, the Census Bureau(统计局) reported today.
The 90,031,000 families in the United States averaged 2.64 members each as of last July 1.“The reason is, in effect, changes in the age structure,” explained Campbell Gibson, a population researcher for the bureau. Most Americans born in the great explosion of births are now in their 20’s and 30’s when they most likely to set up families, he said.
The fact that many are doing so increased the number of families from 80.4 million in 1980 t0 88.8 million in 1986 and past the 90 million mark last summer.
At the same time, the average number of people per family dropped from 2.75 in 1985 to 2.65 in 1986 and then to 2.64, Mr Gibson said.
By comparison, the 1970 Census found the average family contained 3.14 people. Families averaged more than four people in 1939 and more than five in 1880.
The growing number of ever---- smaller families is still going on, but Mr Gibson pointed out that family growth was not the same as population increase in the 1970’s.
The same age factors that are increasing the number of families also happened then, but in the 1970’s the proportion(比例) of families in each age group was also growing.
That hasn’t continued in the 1980’s for a number of possible reasons, Mr Gibson said. For example, in the 1980’s more young people have chosen to remain home with their parents instead of setting up housekeeping on their own, as many did in the 1970’s.
This could be caused by the increasing cost of housing, he said. Delays in marriage while young people go to work and school, have also been widely reported as a factor, but it was not the only factor for the family changes.
1.The smaller figure of families reported here is _________.
A.1980 | B.80,400,000 | C.2.64 | D.90 million |
2.What’s the reporter’s attitude towards the present situation?
A. People should get married at later age.
The average number of family members should be 2.64. It’s not clear in the report. Young people should set up housekeeping on their own, as many did in the 1970’s.3.From the last paragraph we may infer that________.
A. delay in marriage will not help the number of the families
delay in marriage is the major factor of the family changes the writer felt sorry that many young people now delay their marriages there must be some other factors which have led to the slower growth in the 1980’s4. The underlined word “factor” in the passage means_________.
A.reason | B.something that proves be true |
C.advantage | D.something that helps to bring about a result |
高二英语阅读理解中等难度题查看答案及解析