They make a guest appearance in at least half of the articles on Medical News Today. They are responsible for many of the biggest breakthroughs in medicine. However, the humble lab mice also shoulder much of the blame when the failure of drugs to translate from animal models to humans keeps worrying the whole of medical research. Should scientists abandon lab mice altogether?
Mice were introduced into the lab back in the 1920s. An ambitious young American geneticist Clarence Cook Little strongly believed that cancer was an inheritable (有遗传性的) disease, and that mice were the ideal subjects for his experiments.
Other animals were, and still are, used to study disease. Cats and dogs are popular, as well as chimpanzees. Of course, ethical (伦理的) considerations get more complicated the further up the food chain you go. And mice are in sufficient numbers for researchers to conduct thousands of trials. Add to that the problem of cost: A standard lab mouse costs about $20---far cheaper than a healthy cat or dog. So their importance in scientific research has become well-established.
We share more than 97 percent of our working DNA with mice, a consequence of a shared ancestor 75 million years ago. This similarity has been both a blessing and a curse. While we share many basic biological processes, it is the three percent of the genes which set us apart from mice that can have a big influence on how our bodies work.
Mice may not always be the perfect model for understanding our own bodies, but they do hold real value to researchers. Their usefulness will only increase as scientists work out better ways to modify (修改) their genes to compensate for their shortcomings. The difficult part of the issue may be that researchers need to be more critical as they evaluate the type of model that is best for their experiment.
In the end, the story of scientists’ relationship with lab mice will possibly be one of gradual advances to improve an imperfect system. This is exactly how most scientific research progresses — by critically examining what we know to expand our knowledge of what we do not.
1.What does the underlined word “they” in the first paragraph refer to?
A.American geneticists B.cats and dogs
C.lab mice D.breakthroughs in medicine
2.Paragraph 4 mainly answers the question “________?”
A.Why do drugs that work in mice fail when tried in humans
B.Why are mice the ideal subjects for medical research
C.Why do we and mice share more than 97% of our working DNA
D.How can we understand our own bodies by studying lab mice
3.Which of the following statements is TRUE according to the passage?
A.Mice are in sufficient numbers because they are at the lower part of the food chain.
B.Many scientist are considering stopping the use of lab mice.
C.More genetically modified mice will be used in medical research in the near future.
D.It will become easier for researchers to choose the proper type of lab mice.
4.What is the author’s attitude to the use of lab mice?
A.Disappointed B.Supportive
C.Indifferent D.disapproving
高三英语阅读理解中等难度题
They make a guest appearance in at least half of the articles on Medical News Today. They are responsible for many of the biggest breakthroughs in medicine. However, the humble lab mice also shoulder much of the blame when the failure of drugs to translate from animal models to humans keeps worrying the whole of medical research. Should scientists abandon lab mice altogether?
Mice were introduced into the lab back in the 1920s. An ambitious young American geneticist Clarence Cook Little strongly believed that cancer was an inheritable (有遗传性的) disease, and that mice were the ideal subjects for his experiments.
Other animals were, and still are, used to study disease. Cats and dogs are popular, as well as chimpanzees. Of course, ethical (伦理的) considerations get more complicated the further up the food chain you go. And mice are in sufficient numbers for researchers to conduct thousands of trials. Add to that the problem of cost: A standard lab mouse costs about $20---far cheaper than a healthy cat or dog. So their importance in scientific research has become well-established.
We share more than 97 percent of our working DNA with mice, a consequence of a shared ancestor 75 million years ago. This similarity has been both a blessing and a curse. While we share many basic biological processes, it is the three percent of the genes which set us apart from mice that can have a big influence on how our bodies work.
Mice may not always be the perfect model for understanding our own bodies, but they do hold real value to researchers. Their usefulness will only increase as scientists work out better ways to modify (修改) their genes to compensate for their shortcomings. The difficult part of the issue may be that researchers need to be more critical as they evaluate the type of model that is best for their experiment.
In the end, the story of scientists’ relationship with lab mice will possibly be one of gradual advances to improve an imperfect system. This is exactly how most scientific research progresses — by critically examining what we know to expand our knowledge of what we do not.
1.What does the underlined word “they” in the first paragraph refer to?
A.American geneticists B.cats and dogs
C.lab mice D.breakthroughs in medicine
2.Paragraph 4 mainly answers the question “________?”
A.Why do drugs that work in mice fail when tried in humans
B.Why are mice the ideal subjects for medical research
C.Why do we and mice share more than 97% of our working DNA
D.How can we understand our own bodies by studying lab mice
3.Which of the following statements is TRUE according to the passage?
A.Mice are in sufficient numbers because they are at the lower part of the food chain.
B.Many scientist are considering stopping the use of lab mice.
C.More genetically modified mice will be used in medical research in the near future.
D.It will become easier for researchers to choose the proper type of lab mice.
4.What is the author’s attitude to the use of lab mice?
A.Disappointed B.Supportive
C.Indifferent D.disapproving
高三英语阅读理解中等难度题查看答案及解析
Mars(火星) appears to be flowing with small streams of salty water, at least in the summer, scientists reported Monday. “It suggests that it would be possible for there to be life today on Mars,” NASA’s science mission chief, John Grunsfeld, said at a news conference on September 28, 2015.
The streams are about 12 to 15 feet wide and 300 feet or more long, scientists said. “What we’re dealing with is wet soil, thin layers of wet soil, not standing water,” said Aifred McEwen of the University of Arizona at Tueson, the principal scientist for the Mars Reconnaissance Orbiter’s high-resolution imaging experiment.
Because liquid water is essential to life, the findings could have major implications for the possibility of Martian life. The researchers said further exploration is needed to determine whether microscopic life exists on the planet.
The presence of liquid water could also make life easier for astronauts visiting or living on Mars. Water could be used for drinking and for creating oxygen and rocket fuel. NASA’s goal is to send humans there in the 2030s.
The evidence of flowing water consists largely of dark, narrow streaks(条痕) on the surface that tend to appear and grow during the warmest Martian months and fade the rest of the year.
Mars is extremely cold even in summer, and the streaks are in places where the temperature is as low as minus 10 degrees Fahrenheit. But salt can lower the freezing point of water and melt ice.
The source of the water is a mystery. Scientists noted it could be melting ice. It could be an underground aquifer, which is rock or sand that can hold water. It is possibly water vapor from the thin Martian atmosphere. Or it may be a combination Michael Meyer, lead scientist for NASA’s Mars exploration program, said the only definitive way for now to determine whether there’s life on Mars is to collect rocks and soil for analysis on Earth—something a U. S. lander set for lift-off in 2020 will do.
1.According to John Grunsfeld, there seems to be on Mars.
A.salty water B.standing water
C.rocket fuel D.human beings
2.Scientists are uncertain about the of the water on Mars.
A.state B.source
C.temperature D.taste
3.What matters to the existence of liquid water on Mars?
A.The distance from the sun B.The favorable climate
C.The gravity of the earth D.The salt in it
4.What would be the best title for the text?
A.Streams of Water Spotted on Mars
B.Astronauts will Land on Mars
C.NASA’s Mars Exploration Program
D.A Breakthrough in the Exploration of Mars
高三英语阅读理解中等难度题查看答案及解析
Mars( 火星) appears to be flowing with small streams of salty water, at least in the summer,scientists reported Monday. "It suggests that. it would be possible for there to be life today on Mars," NASA's science mission chief, John Grunsfeld, said at a news conference on September 28, 2015. The streams are about 12 to 15 feet wide and 300 feet or more long, scientists said.
"What we're dealing with is wet soil. thin layers of wet soil, not standing water," said Aifred McEwen of the University of Arizona at Tueson ! the principal scientist for the Mars Reconnaissance Orbiter's high-resolution imaging experiment.
Because liquid water is essential to life, the findings could have major implications for the possibility of Martian life. The researchers said further exploration is needed to determine whether microscopic life exists on the planet.
The presence of liquid water could also make life easier for astronauts visiting or living on Mars. Water could be used for drinking and for creating oxygen and rocket fuel. NASA's goal is to send humans there in the 2030s.
The evidence of flowing water consists largely of dark, narrow streaks(条痕) on the surface that tend to appear and grow during the warmest Martian months and fade the rest of the year.
Mars is extremely cold even in summer, and the streaks are in places where the temperature is as low as minus 10 degrees Fahrenheit. But salt can lower the freezing point of water and melt ice.
The source(源头) of the water is a mystery. Scientists noted it could be melting ice. It could be an underground aquifer, which is rock or sand that can hold water. It is possibly water vapor from the thin Martian atmosphere, Or it may be a combination Michael Meyer, lead scientist for NASA's Mars exploration program, said the only definitive way for now to determine whether there's life on Mars is to collect rocks and soil for analysis on Earth - something a U. S. lander set for lift-off in 2020 will do.
1.What would be the best title for the text? '
A Streams of Water Spotted on Mars
B. Astronauts will Land on Mars
C. NASA's Mars Exploration Program
D. A Breakthrough in the Exploration of Mars
2.According to John Grunsfeld, there seems to be on Mars.
A. salty water
B. standing water
C. rocket fuel
D. human beings
3.Scientists are uncertain about the of the water on Mars.
A. state
B. source
C. temperature
D. taste
4.What matters to the existence of liquid water on Mars?
A. The distance from the sun.
B. The favorable climate.
C. The gravity of the earth
D.The salt in it.
高三英语阅读理解中等难度题查看答案及解析
C
Mars( 火星) appears to be flowing with small streams of salty water, at least in the summer, scientists reported Monday."It suggests that.it would be possible for there to be life today on Mars," NASA's science mission chief, John Grunsfeld, said at a news conference on September 28, 2015.
The streams are about 12 to 15 feet wide and 300 feet or more long, scientists said."What we're dealing with is wet soil.thin layers of wet soil, not standing water," said Aifred McEwen of the University of Arizona at Tueson ! the principal scientist for the Mars Reconnaissance Orbiter's high-resolution imaging experiment.
Because liquid water is essential to life, the findings could have major implications for the possibility of Martian life.The researchers said further exploration is needed to determine whether microscopic life exists on the planet.
The presence of liquid water could also make life easier for astronauts visiting or
living on Mars.Water could be used for drinking and for creating oxygen and rocket
fuel.NASA's goal is to send humans there in the 2030s.
The evidence of flowing water consists largely of dark, narrow streaks(条痕) on
the surface that tend to appear and grow during the warmest Martian months and fade
the rest of the year.
Mars is extremely cold even in summer, and the streaks are in places where the
temperature is as low as minus 10 degrees Fahrenheit.But salt can lower the freezing point of water and melt ice.
The source of the water is a mystery.Scientists noted it could be melting
ice.It could be an underground aquifer, which is rock or sand that can hold water.It is possibly water vapor from the thin Martian atmosphere, Or it may be a combination Michael Meyer, lead scientist for NASA's Mars exploration program, said the only definitive way for now to determine whether there's life on Mars is to collect rocks and soil for analysis on Earth - something a U.S.lander set for lift-off in 2020 will do.
1.What would be the best title for the text? '
A.Streams of Water Spotted on Mars
B.Astronauts will Land on Mars
C.NASA's Mars Exploration Program
D.A Breakthrough in the Exploration of Mars
2.According to John Grunsfeld, there seems to be on Mars.
A.salty water
B.standing water
C.rocket fuel
D.human beings
3.Scientists are uncertain about the of the water on Mars.
A.state
B.source
C.temperature
D.taste
4.What matters to the existence of liquid water on Mars?
A.The distance from the sun.
B.The favorable climate.
C.The gravity of the earth
D.The salt in it.
高三英语阅读理解中等难度题查看答案及解析
Mars( 火星) appears to be flowing with small streams of salty water, at least in the summer, scientists reported Monday. "It suggests that. it would be possible for there to be life today on Mars," NASA's science mission chief, John Grunsfeld, said at a news conference on September 28, 2015.
The streams are about 12 to 15 feet wide and 300 feet or more long, scientists said. "What we're dealing with is wet soil. thin layers of wet soil, not standing water," said Aifred McEwen of the University of Arizona at Tueson ! the principal scientist for the Mars Reconnaissance Orbiter's high-resolution imaging experiment.
Because liquid water is essential to life, the findings could have major implications for the possibility of Martian life. The researchers said further exploration is needed to determine whether microscopic life exists on the planet.
The presence of liquid water could also make life easier for astronauts visiting or living on Mars. Water could be used for drinking and for creating oxygen and rocket fuel. NASA's goal is to send humans there in the 2030s.
The evidence of flowing water consists largely of dark, narrow streaks(条痕) on the surface that tend to appear and grow during the warmest Martian months and fade the rest of the year.
Mars is extremely cold even in summer, and the streaks are in places where the temperature is as low as minus 10 degrees Fahrenheit. But salt can lower the freezing point of water and melt ice.
The source(源头) of the water is a mystery. Scientists noted it could be melting ice. It could be an underground aquifer, which is rock or sand that can hold water. It is possibly water vapor from the thin Martian atmosphere, Or it may be a combination.
Michael Meyer, lead scientist for NASA's Mars exploration program, said the only definitive way for now to determine whether there's life on Mars is to collect rocks and soil for analysis on Earth - something a U. S. lander set for lift-off in 2020 will do.
1.What would be the best title for the text?
A Streams of Water Spotted on Mars
B. Astronauts will Land on Mars
C. NASA's Mars Exploration Program
D. A Breakthrough in the Exploration of Mars
2.According to John Grunsfeld, there seems to be on Mars.
A. salty water
B. standing water
C. rocket fuel
D. human beings
3.Scientists are uncertain about the of the water on Mars.
A. state
B. source
C. temperature
D. taste
4.What matters to the existence of liquid water on Mars?
A. The distance from the sun.
B. The favorable climate.
C. The gravity of the earth
D.The salt in it.
高三英语阅读理解中等难度题查看答案及解析
Mars(火星)appears to be flowing with small streams of salty water,at least in the summer,scientists reported Monday."It suggests that it would be possible for there to be life today on Mars," NASA's science mission chief,John Grunsfeld,said at a news conference on September 28,2015.
The streams are about 12 to 15 feet wide and 300 feet or more long,scientists said."What we're dealing with is wet soil.Thin layers of wet soil,not standing water," said Aifred McEwen of the University of Arizona at Tueson,the principal scientist for the Mars Reconnaissance Orbiter's high-resolution imaging experiment.
Because liquid water is extremely necessary to life,the findings could have major possible effects for the possibility of Martian life.The researchers said further exploration is needed to determine whether microscopic life exists on the planet.
The presence of liquid water could also make life easier for astronauts visiting or living on Mars.Water could be used for drinking and for creating oxygen and rocket fuel.NASA's goal is to send humans there in the 2030s.
The evidence of flowing water consists largely of dark,narrow streaks(条痕)on the surface that tend to appear and grow during the warmest Martian months and fade the rest of the year.
Mars is extremely cold even in summer,and the streaks are in places where the temperature is as low as minus 10 degrees Fahrenheit.But salt can lower the freezing point of water and melt ice.
The source of the water is a mystery(神秘的事物).Scientists noted it could be melting ice.It could be an underground aquifer(砂石含水层),which is rock or sand that can hold water.It is possibly water vapor from the thin Martian atmosphere,or it may be a combination Michael Meyer,lead scientist for NASA's Mars exploration program, said the only definitive way for now to determine whether there's life on Mars is to collect rocks and soil for analysis on Earth-something a U.S.lander set for lift-off in 2020 will do.
1.What matters to the existence of liquid water on Mars?
A. The distance from the sun. B. The favorable climate.
C. The gravity of the earth. D. The salt in it.
2.According to John Grunsfeld,on Mars there seems to be .
A. salty water B. standing water
C. rocket fuel D. human beings
3.Scientists are uncertain about the of the water on Mars.
A. state B. source
C. temperature D. taste
4.What would be the best title for the text?
A. Streams of Water Spotted on Mars
B. Astronauts Will Land on Mars
C. NASA's Mars Exploration Program
D. A Breakthrough in the Exploration of Mars
高三英语阅读理解中等难度题查看答案及解析
D
Mars(火星)appears to be flowing with small streams of salty water,at least in the summer,scientists reported Monday.“It suggests that.it would be possible for there to be life today on Mars,”NASA's science mission chief,John Grunsfeld,said at a news conference on September 28,2015.
The streams are about 12 to 15 feet wide and 300 feet or more long,scientists said.“What we're dealing with is wet soil.thin layers of wet soil,not standing water,”said Aifred McEwen of the University of Arizona at Tueson!the principal scientist for the Mars Reconnaissance Orbiter's high-resolution imaging experiment.
Because liquid water is essential to life,the findings could have major implications for the possibility of Martian life.The researchers said further exploration is needed to determine whether microscopic life exists on the planet.
The presence of liquid water could also make life easier for astronauts visiting or living on Mars.Water could be used for drinking and for creating oxygen and rocket fuel.NASA's goal is to send humans there in the 2030s.
The evidence of flowing water consists largely of dark,narrow streaks(条痕) on the surface that tend to appear and grow during the warmest Martian months and fade the rest of the year.
Mars is extremely cold even in summer,and the streaks are in places where the temperature is as low as minus 10 degrees Fahrenheit.But salt can lower the freezing point of water and melt ice.
The source(源头)of the water is a mystery.Scientists noted it could be melting ice.It could be an underground aquifer,which is rock or sand that can hold water.It is possibly water vapor from the thin Martian atmosphere,Or it may be a combination Michael Meyer,lead scientist for NASA's Mars exploration program,said the only definitive way for now to determine whether there's life on Mars is to collect rocks and soil for analysis on Earth - something a U.S.lander set for lift-off in 2020 will do.
1.What would be the best title for the text?
A.Streams of Water Spotted on Mars
B.Astronauts will Land on Mars
C.NASA's Mars Exploration Program
D.A Breakthrough in the Exploration of Mars
2.According to John Grunsfeld,there seems to be ________on Mars.
A.salty water
B.standing water
C.rocket fuel
D.human beings
3.Scientists are uncertain about the __________of the water on Mars.
A.state B.source C.temperature D.taste
4.What matters to the existence of liquid water on Mars?
A.The distance from the sun.
B.The favorable climate.
C.The gravity of the earth
D.The salt in it.
高三英语阅读理解简单题查看答案及解析
There are around 6,000 living languages in the world—and at least half of these are in danger. In every part of the world, languages are disappearing. In fact, one scientist has said that languages are in more danger of extinction than birds or animals. Professor Steve Sutherland of the University of East Anglia says that in the past 500 years 4.5 percent of languages have died out—compared with 1.3 percent of birds, and 1.9 percent of mammals.
Languages come and go, and thousands have done exactly that without leaving any trace(痕迹). Only a very few—Basque, Greek and Latin among them—have lasted more than 2000 years. But it seems that the pace of their disappearance is becoming quicker.
The Ethnologue, a database of all the languages spoken in the world, states that 417 languages are spoken by so few people that they are in the final stages of becoming extinct. If very few people speak a language, it will probably die out.
Languages may be lost through migration, as people move from small towns to city centers, or when environments are destroyed by the search for oil or wood. Natural disasters can also devastate populations, and along with them, their language. Governments also play a role in the extinction of languages. The need to establish “official languages”, for a country to educate its children and carry out its business, had a disastrous effect on many small languages.
What is lost if a language is lost? Some people argue that languages die as the human race develops. Obviously there could be great benefits if everyone in the world spoke the same language—some industries already reflect this, with English essential for pilots and air traffic controllers. But there are more important things than convenience. As languages are lost, whole ways of life and knowledge may be lost along with them.
To put it simply, language expresses something about who we are, about where we live in the world. Ani Rauhihi, a Maori teacher in New Zealand’s North Island, sums it up: “If you grow up speaking our language, you won’t know who you are.”
1.What do the figures mentioned in the first paragraph suggest?
A. Most languages have died out completely.
B. Languages are in great danger of extinction.
C. Languages are disappearing slower than before.
D. Animals are disappearing faster than languages.
2.What can best replace the underlined word “devastate” ?
A. raise
B. control
C. improve
D. destroy
3.What if a language is lost according to the passage?
A. There will be great trouble.
B. There is no need to worry about it.
C. Its culture and knowledge will also be lost.
D. People will be able to communicate with others conveniently.
4.What can we infer from the last paragraph?
A. Languages reflect our identity.
B. People will speak the same language one day.
C. Ani Rauhihi cares less about languages dying out.
D. Fewer people will remember their own languages.
高三英语阅读理解简单题查看答案及解析
—What do you think of the price of the computers at this store?
—They are at least equal in price to, if not cheaper than, _____ at any other store.
A.one B.ones C.that D.those
高三英语单项填空中等难度题查看答案及解析
—What do you think of the price of these computers?
—They are at least equal in price to, if not cheaper than, ________ in other companies.
A. it B. ones C. that D. the ones
高三英语单项填空中等难度题查看答案及解析