Many research groups are testing “ink” made f...

Many research groups are testing “ink” made from silk proteins to print human tissues, even organs. The process is a less costly alternative to conventional 3-D printing with collagen, a key protein mainly existing in the mammal’s (哺乳动物) cells. Researchers in Assam, a state in India, are investigating using local silkworm species for the task—they recently submitted a patent for bioinks using a combination of proteins obtained from local silkworms. The scientists have woven them into tissue structures ranging from ears to heart.

Silk is a natural substance which is strong and completely biodegradable (可生物降解的), well suited for applications in tissue engineering. For instance, to bio-print an ear, researchers dissolve silk fibers. They carefully mix the sticky liquid with a patient’s stem cells, then build structures layer by layer with a 3-D printer. Finally, the cells grow and replace the silken proteins and finally change into a natural substance in human body.

Compared with common—used chemicals as adhesive (黏合剂), wild silk is also perfect to cross-link silky tissues, which helps to maintain a 3-D structure. Also, the wild silk has spots that cells naturally attach to, which allows cells to stick to the silk structure rapidly. “These silks are ideal candidates for bioinks because they can be combined to build strong human tissues” says Mandal, the lab’s lead investigator. “This is important, for example, when making bones,” he add.

“Obtaining and purifying collagen from animal remains is complex and expensive.” says David Kaplan, an expert in biomedical engineering, when asked about the advantages. Compared with collagen, silks have an immense advantage in terms of supply and processing. Local sourcing is also a clear plus in their use in India.”

Mandal and his colleagues have already created original structures, including bone and soft tissues of the heart and liver. Reconstructing a human knee complex tissue at the ends of a bone will be next.

1.What does the underlined word “bioinks” refer to?

A.Silk proteins. B.Collagens.

C.Certain chemical. D.Tissues.

2.What will a patient eventually get after an ear-bioprinting?

A.An artificial ear. B.A silken ear.

C.A real ear. D.An original ear.

3.What are the advantages of silk proteins over collagen according to David Kaplan?

A.They are biodegradable and strong.

B.They are inexpensive and uncomplicated.

C.They are harmless and attachable.

D.They are pure and available.

4.What is the best title for the text?

A.Final Solution—Wild Worms for Medical Treatment.

B.Silky Tissue—Worm Proteins Ready for 3-D Bioprinting.

C.Bioink—Cheap Alternative for Conventional Operations.

D.Protein—Key to Repairing Human Organs.

高三英语阅读理解中等难度题查看答案及解析

B

American researchers found females are the more talkative sex because of a special “language protein” in the brain.

The study, conducted by neuroscientists(神经学家) and psychologist from the University of Maryland, concluded that women talked more because they had more of the Foxp2 protein. The research, published in the Journal of Neuroscience, found that higher levels were found among humans that were women but in rats that were males. Their findings came after it was previously claimed that ladies speak about 20,000 words a day – over 13,000 more than men. “This study is one of the first to report a sex difference in the expression of a language-associated protein in humans or animals,” said Prof Margaret McCarthy, who led the study. In their study, the researchers attempted to determine what might make male rats more vocal than their female friends.

They separated four-day-old rats from their mothers and then counted the number of times they cried out in the “ultrasonic（超声波的） range”, the frequencies higher than humans can hear, over five minutes. While both sexes called out hundreds of cries, the males called out twice as often, they found. But when the pups were returned to their mother’s cage, she fussed over her sons first. Tests conducted on the parts of the brain known to be associated with vocal calls showed the male pups have up to twice as much Foxp2 protein as the females. The researchers then increased the production in the brains of female pups and reduced it in males. This led to the female rats crying out more often and their mothers showing more interest to them. In contrast, males became less “talkative”.

The researchers then tested samples from ten children, aged between three and five, which showed that females had up to 30 per cent more of the Foxp2 protein than males, in a brain area key to language in humans.

“Based on our observations, we assume higher levels of Foxp2 in girls and higher levels of Foxp2 in male rats is an indication that Foxp2 protein levels are associated with the more communicative sex,” said Prof McCarthy.

“Our results imply Foxp2 as a component (成分)of the neurobiological basis of sex differences in vocal communication in mammals.”

1.From the second paragraph, we can learn that ________.

A. women always speak more words than men

B. men and male rats have low levels of language protein

C. women and male rats have similar levels of Foxp2

D. McCarthy isn’t the first to find females more talkative

2.The underlined phrase “fussed over” in the third paragraph probably means______.

A. paid attention to　　 B. related to

C. put pressure on　 　　 D. counted on

3.The researchers carried out the experiments on rats in order to _______.

A. test which part of the brain is key to language in rats and humans

B. prove the levels of Foxp2 protein in humans and rats are different

C. determine the reason why female rats are more talkative than male rats

D. discover the association between Foxp2 protein and vocal communication

4.Which of the following can be the best title for the passage?

A. Tests on humans and rats

B. Why women are the talkative sex

C. Sex differences in Foxp2 protein

D. Foxp2 protein determines oral ability

高三英语阅读理解中等难度题查看答案及解析

B

American researchers found females are the more talkative sex because of a special “language protein(蛋白质)” in the brain.

The study, conducted by neuroscientists (神经学家)and psychologist from the University of Maryland, concluded that women talked more because they had more of the Foxp2 protein. The research, published in the Journal of Neuroscience, found that higher levels were found among humans that were women but in rats that were males. Their findings came after it was previously claimed that ladies speak about 20,000 words a day – over 13,000 more than men. “This study is one of the first to report a sex difference in the expression of a language-associated protein in humans or animals,” said Prof Margaret McCarthy, who led the study. In their study, the researchers attempted to determine what might make male rats more vocal than their female friends.

They separated four-day-old rats from their mothers and then counted the number of times they cried out in the “ultrasonic range”, the frequencies higher than humans can hear, over five minutes. While both sexes called out hundreds of cries, the males called out twice as often, they found. But when the pups were returned to their mother’s cage, she fussed over her sons first. Tests conducted on the parts of the brain known to be associated with vocalcalls showed the male pups have up to twice as much Foxp2 protein as the females. The researchers then increased the production in the brains of female pups and reduced it in males. This led to the female rats crying out more often and their mothers showing more interest to them. In contrast, males became less “talkative”.

The researchers then tested samples from ten children, aged between three and five, which showed that females had up to 30 per cent more of the Foxp2 protein than males, in a brain area key to language in humans.

“Based on our observations, we assume higher levels of Foxp2 in girls and higher levels of Foxp2 in male rats is an indication that Foxp2 protein levels are associated with the more communicative sex,” said Prof McCarthy. “Our results imply Foxp2 as a component of the neurobiological basis of sex differences in vocal communication in mammals. “

1.What can be inferred from the second paragraph？

A. women always speak more words than men.

B. men and male rats have low levels of language protein.

C. McCarthy isn’t the first to find females more talkative

D. women and male rats have similar levels of Foxp2.

2.What does the underlined phrase “fussed over” in the third paragraph mean?

A.relyed on　 　　　　 B. related to

C. put pressure on　 D. paid attention to

3. What’s the purpose of the experiments on rats carried out by the researchers?

A.To test which part of the brain is key to language in rats and humans.

B. To discover the association between Foxp2 protein and vocal communication.

C. To determine the reason why female rats are more talkative than male rats.

D. To prove the levels of Foxp2 protein in humans and rats are different.

4.Which of the following can be the best title for the passage ?

A. Why women are the talkative sex

B. Tests on humans and rats

C. Sex differences in Foxp2 protein

D. Foxp2 protein determines oral ability

高三英语阅读理解中等难度题查看答案及解析

How _____ you say that you have made great progress since there are so many mistakes in your test paper ?

A．can       B．must        C．need       D．may

高三英语单项填空中等难度题查看答案及解析

阅读下面短文，在空白处填入1个适当的单词或括号内单词的正确形式。

A group of researchers and scientists from China and other countries are working together　 1. (record) and collect digital images of cultural relics from the Mogao Caves, which were a key stop 2. the Silk Road throughout China's ancient history. Nearly 500,000 high quality digital photographs 3.( produce) since the international project started in 1994.

The Mogao Caves 4.(study) in many countries have long been a meeting point for different cultures. Today the caves are just as international as they were at the time5.people travelled the Silk Road. Tourists from all over the world visit Dunhuang to see the caves, and the Getty Museum in Los Angeles has reproduced a copy of the caves and6.(paint) for people to admire in America.

By sharing so many digital photos over the Internet, the group hopes to promote even 7.(wide) interest around the world in China's ancient history, culture, and traditions.8.one researcher who is working on the project explains, “9.(appreciate) one's own cultural heritage is very important for understanding oneself. Recognizing the cultural heritage of other countries 10. (do) good to international communication and understanding."

高三英语语法填空中等难度题查看答案及解析

阅读下面短文，在空白处填入1个适当的单词或括号内单词的正确形式。

A group of researchers and scientists from China and other countries are working together to help increase 1. (appreciate) of China’s ancient cultural heritage. They are recording and collecting digital images of cultural relics from the Magao Caves, 2. were a key stop along the Silk Road throughout China’s ancient history. Nearly 500,000 high-quality digital photographs 3. (produce) since the international project started in 1994.

The Magao Caves have long been 4. meeting point for different cultures. Today, the caves are just as international as they 5. (be) at the time when people travelled the Silk Road. Tourists from all over the world visit Dunhuang to see the caves, and the Getty Museum in Los Angeles has even reproduced a copy of the caves and paintings for people 6. (admire) in America.

By7. (share) so many digital photos over the Internet, the group hopes to promote even 8. (wide) interest around the world in China’s ancient history, culture, and traditions. They also hope to further educate people about the importance of safeguarding historic and cultural relics for future 9. (generation) to understand and appreciate. As one researcher who is working 10. the project explains, “Appreciating the cultural heritage is very important for international communication and understanding.”

高三英语语法填空中等难度题查看答案及解析

Research _______ that over 90 percent of high school students are dissatisfied with their test scores.

高三英语单项填空简单题查看答案及解析

With so many noises from the busy traffic in the street, I couldn’t_____ and do my research work.

A. put down　　 B. settle down

C. cut down　 D. set down

高三英语单项填空中等难度题查看答案及解析

Give yourself a test. Which way is the wind blowing? How many kinds of wildflowers can be seen from your front door? If your awareness is as sharp as it could be, you’ll have no trouble answering these questions.

Most of us observed much more as children than we do as adults. A child’s day is filled with fascination, newness and wonder. Curiosity gave us all a natural awareness. But distinctions that were sharp to us as children become unclear; we are numb(麻木的）to new stimulation(刺激), new ideas. Relearning the art of seeing the world around us is quite simple, although it takes practice and requires breaking some bad habits.

The first step in awakening senses is to stop predicting what we are going to see and feel before it occurs. This blocks awareness. One chilly night when I was hiking in the Rocky Mountains with some students, I mentioned that we were going to cross a mountain stream. The students began complaining about how cold it would be. We reached the stream, and they unwillingly walked ahead. They were almost knee-deep when they realized it was a hot spring. Later they all admitted they’d felt cold water at first.

Another block to awareness is the obsession(痴迷) many of us have with naming things. I saw bird watchers who spotted a bird, immediately looked it up in field guides, and said, a "ruby-crowned kinglet" and checked it off. They no longer paid attention to the bird and never learned what it was doing.

The pressures of "time" and "destination" are further blocks to awareness. I encountered many hikers who were headed to a distant camp-ground with just enough time to get there before dark. It seldom occurred to them to wander a bit, to take a moment to see what’s around them. I asked them what they’d seen. "Oh, a few birds," they said. They seemed bent on their destinations.

Nature seems to unfold to people who watch and wait. Next time you take a walk, no matter where it is, take in all the sights, sounds and sensations. Wander in this frame of mind and you will open a new dimension to your life.z.

1.According to Paragraph 2, compared with adults, children are more ____________.

A.anxious to do wonders

B.sensitive to others’ feelings

C.likely to develop unpleasant habits

D.eager to explore the world around them

2.What idea does the author convey in Paragraph 3?

A.To avoid jumping to conclusions.

B.To stop complaining all the time.

C.To follow the teacher’s advice.

D.To admit mistakes honestly.

3.The bird watchers’ behavior shows that they __________.

A.are very patient in their observation

B.are really fascinated by nature

C.care only about the names of birds

D.question the accuracy of the field guides

4.Why do the hikers take no notice of the surroundings during the journey?

A.The natural beauty isn’t attractive to them.

B.They focus on arriving at the camp in time.

C.The forest in the dark is dangerous for them.

D.They are keen to see rare birds at the destination.

5.In the passage, the author intends to tell us we should __________.

A.fill our senses to feel the wonders of the world

B.get rid of some bad habits in our daily life

C.open our mind to new things and ideas

D.try our best to protect nature

高三英语阅读理解困难题查看答案及解析

Give yourself a test. Which way is the wind blowing? How many kinds of wildflowers can be seen from your front door? If your awareness is as sharp as it could be, you”ll have no trouble answering these questions.

Most of us observed much more as children than we do as adults. A child’s day is filled with fascination, newness and wonder. Curiosity gave us all a natural awareness, but distinctions that were sharp to us as children become unclear, we are numb (麻木的) to new stimulation (剌激), new ideas. Relearning the art of seeing the world around us is quite simple, although it takes practice and requires breaking some bad habits.

The first step in awakening senses is to stop predicting what we are going to see and feel before it occurs. This blocks awareness. One chilly night when I was hiking in the Rocky Mountains with some students, I mentioned that we were going to cross a stream. The students began complaining about how cold it would be. We reached the stream and they unwillingly walked ahead. They were almost knee-deep when they realized it was a hot spring. Later they all admitted they'd felt cold water at first.

Another block to awareness is the obsession (痴迷) many of us have with naming things. I saw bird watchers who spotted a bird, immediately looked it up in field guides , and said, a “ruby-crowned kinglet” and checked it off. They no longer paid attention to the bird and never learned what it was doing.

The pressures of “time” and “destination” are further blocks to awareness. I encountered many hikers who were headed to a distant camp-ground with just enough time to get there before dark. It seldom occurred to them to wander a bit, to take a moment to see what’s around them. I asked them what they’d seen. “Oh, a few birds,” they said. They seemed bent on their destinations.

Nature seems to unfold to people who watch and wait next time you take a walk, no matter where it is, take in all the sights, sounds and sensations. Wander in this frame of mind and you will open a new dimension to your life.

1.According to Paragraph 2, compared with adults, children are more ______.

A.anxious to do wonders B.sensitive to others’ feelings

C.likely to develop unpleasant habits D.eager to explore the world around them

2.Why do the hikers take no notice of the surroundings during the journey?

A.They are keen to see rare birds at the destination.

B.They focus on arriving at the camp in time.

C.The natural beauty isn’t attractive to them.

D.The forest in the dark is dangerous for them.

3.In the passage, the author intends to tell us we should ______.

A.fill our senses to feel the wonders of the world

B.get rid of some bad habits in our daily life

C.open our mind to new things and ideas

D.try our best to protect nature

高三英语阅读理解中等难度题查看答案及解析