Scientists have discovered a "monster black hole" so massive that, in theory, it shouldn't exist
It’s a stellar black hole---the type that forms after stars die, collapse, and explode. Researchers had previously believed that the size limit was no more than 20 times the mass of our sun because 8S these stars die, they lose most of their mass through explosions that expel matter and gas swept away by stellar winds
This theory has now been toppled by LB-1, the newly discovered black hole. Located about 15.000 light years away, it has a mass 70 times greater than our sun, according to a press release from the Chinese Academy of Sciences.
The findings were published by Chinese researchers in the journal Nature on Wednesday.
"Black boles of such mass should not even exist in our galaxy, according to most of the current models of stellar evolution," said Liu Jifeng, head of the team that made the discovery. "LB-1 is twice as massive as what we thought possible. Now theorists will have to take up the challenge of explaining its formation."
Scientists are now scratching their heads at how LB-1 got so huge.
The Chinese team has proposed a number of theories. LB-1' sheer size suggests that it “was not formed from the collapse of only one star," the study said--- instead, it could potentially be two smaller black holes orbiting each other.
Another possibility is that it formed from “fallback supermova.” This is when a supernoma---the last stage of an exploding star---ejects material during the explosion, which then falls back into the supernova, creating a black hole.
This fallback formation is theoretically possible, but scientists have never been able to prove or observe it. If this is how LB-1 formed, then we may have "direct evidence for this process” for the first time, the study said.
There are several types of black holes and stellar black holes like LB-1 are on the smaller side, according to NASA. Supermassive black holes are much bigger---they can be billions of times the mass of our sun,
Scientists believe supermassive black holes may be connected to the formation of galaxies, as they often exist at the center of the mass star stems but it is still not clear exactly how, or which form first.
1.Why does the writer write the article?
A.To report the great achievement Chinese scientists have made in black hole theory,
B.To inform the readers of the basic knowledge about the black hole,
C.To share with the readers the new development of the black hole discovery,
D.To demonstrate the significance of discovering new black holes for science.
2.Which of the following about LB-1 is true to the passage?
A.It is the biggest black hole ever discovered,
B.It lost only a small part of its mass through explosion.
C.It couldn't have been formed from the collapse of one star,
D.Its discovery may lead to some breakthrough in the “fallback formation theory".
3.Which of the following is right according to the passage?
A.If the sun in our galaxy dies some of its mass will be taken away by stellar winds.
B.A massive supernova will be formed and then exploded if the sun in our galaxy dies.
C."The Milky Way" was formed after a supermassive black hole collapsed and exploded.
D.If “the Milky Way" dies, a supermassive black hole will be formed after its death.
高三英语阅读理解中等难度题
Scientists have discovered a "monster black hole" so massive that, in theory, it shouldn't exist
It’s a stellar black hole---the type that forms after stars die, collapse, and explode. Researchers had previously believed that the size limit was no more than 20 times the mass of our sun because 8S these stars die, they lose most of their mass through explosions that expel matter and gas swept away by stellar winds
This theory has now been toppled by LB-1, the newly discovered black hole. Located about 15.000 light years away, it has a mass 70 times greater than our sun, according to a press release from the Chinese Academy of Sciences.
The findings were published by Chinese researchers in the journal Nature on Wednesday.
"Black boles of such mass should not even exist in our galaxy, according to most of the current models of stellar evolution," said Liu Jifeng, head of the team that made the discovery. "LB-1 is twice as massive as what we thought possible. Now theorists will have to take up the challenge of explaining its formation."
Scientists are now scratching their heads at how LB-1 got so huge.
The Chinese team has proposed a number of theories. LB-1' sheer size suggests that it “was not formed from the collapse of only one star," the study said--- instead, it could potentially be two smaller black holes orbiting each other.
Another possibility is that it formed from “fallback supermova.” This is when a supernoma---the last stage of an exploding star---ejects material during the explosion, which then falls back into the supernova, creating a black hole.
This fallback formation is theoretically possible, but scientists have never been able to prove or observe it. If this is how LB-1 formed, then we may have "direct evidence for this process” for the first time, the study said.
There are several types of black holes and stellar black holes like LB-1 are on the smaller side, according to NASA. Supermassive black holes are much bigger---they can be billions of times the mass of our sun,
Scientists believe supermassive black holes may be connected to the formation of galaxies, as they often exist at the center of the mass star stems but it is still not clear exactly how, or which form first.
1.Why does the writer write the article?
A.To report the great achievement Chinese scientists have made in black hole theory,
B.To inform the readers of the basic knowledge about the black hole,
C.To share with the readers the new development of the black hole discovery,
D.To demonstrate the significance of discovering new black holes for science.
2.Which of the following about LB-1 is true to the passage?
A.It is the biggest black hole ever discovered,
B.It lost only a small part of its mass through explosion.
C.It couldn't have been formed from the collapse of one star,
D.Its discovery may lead to some breakthrough in the “fallback formation theory".
3.Which of the following is right according to the passage?
A.If the sun in our galaxy dies some of its mass will be taken away by stellar winds.
B.A massive supernova will be formed and then exploded if the sun in our galaxy dies.
C."The Milky Way" was formed after a supermassive black hole collapsed and exploded.
D.If “the Milky Way" dies, a supermassive black hole will be formed after its death.
高三英语阅读理解中等难度题查看答案及解析
Scientists have discovered why the Mona Lisa's expression looks so different to different people and at different times.
For centuries, art lovers and critics have been confused by and debated the Leonardo Da Vinci painting's gaze and slight smile.
But new research from the University of California, San Francisco has shed new light on the shining and seemingly changing face of the Mona Lisa.
Through experiments, they discovered that our emotions really do change how we see a neutral face.
Dr Erika Siegel and her colleagues study how our emotions change our perceptions of the world around us—even when we aren't aware that something has changed our feelings.
This relies on the modern theory of" the brain as a predictive organ, instead of a reactive one,” says Dr Siegel.
In other words, “we have a lifetime of experience and we use those experiences to predict what we are going to experience next.”
We all have one dominant eye and one more passive non-dominant one. If each eye is receiving different information, we only consciously perceive what dominant one sees. But non-dominant sights can still enter our subconscious.
They showed 43 people two sets of flashing images simultaneously, so that the dominant eye saw and registered neutral expressions, while the non-dominant eye “saw” flashes of neutral, or smiling faces, which they would only subconsciously be aware of.
After viewing the flashing faces, the researchers showed the participants options of faces and asked them to pick out which ones they had seen.
When their non-dominant eyes had seen a happy face, they were more likely to think the neutral face had actually been smiling, and the same was true for other expressions.
This means that “if you see the Mona Lisa after you have just had a screaming fight with your husband, you're going to see the painting differently,” says Dr Siegel.
“But if you're having the time of your life at the Louvre, you're going to see the mysterious smile,” she adds.
“We are the architects of our own experience. Our brain makes predictions about what it expects to see and uses information from the world to update its expectations,”Dr Siegel says.
1.What is the purpose of Dr Siegel's research?
A.To discover why people perceive the same thing differently.
B.To help appreciate the Mona Lisa.
C.To win a debate.
D.To tell a smiling face from a neutral face.
2.Which of the following is the closest in meaning to “shed new light” in Paragraph 3?
A.Made something bright. B.Provided new explanations.
C.Added light-colored paints. D.Increased amount of natural light.
3.Why did the researchers show the participants two sets of flashing images?
A.To play a game.
B.To pick out their dominant and non-dominant eyes.
C.To strengthen the effect of the non-dominant eyes.
D.To provide images of more expressions.
4.Which of the following can be the best title for the text?
A.Effects of Emotions B.Seeing Is Believing
C.A Mysterious Research D.Is Mona Lisa Smiling?
高三英语阅读理解中等难度题查看答案及解析
Scientists have discovered that rats have adapted to modern human life, even adapting their diets to the cities they live in.
The scientists claim that it could be possible that humans and rats have had similar changes in their genetic make-up, due to modern city life. The downside of the changes in the DNA is that they could make rats susceptible to the same health problems as humans, such as pollutants and sugary foods.
The study showed that rats’ diets have also adapted to their environment. In New York, you can see them eat bagels and beer; in Paris, they like croissants and butter. They adapt in amazing ways. The scientists also analyzed the genomes (基因组)of 29 New York rats and compared them with those of nine brown rats from Heilongjiang Province, north-east China. The finding showed that dozens of rat genes had been through major DNA changes over the centuries, as the rats spread from Asia to Europe and America, and from the countryside and into cities.
The changed genes were associated with diet, behavior, and movement, which added pressures and challenges for the rat to overcome. This could reflect the fact that urban rats have to move through highly artificial environments that are very different from natural habitats. So these gene changes might have evolved to help them move more easily through underground channels and pipes.
As the rats are closely associated with city-living humans, the scientists believe that it is possible that similar changes have happened in both species.
In October 2019, scientists used rats to successfully test an enzyme(酶) that could be used to help people quit smoking. Two groups of rats were trained to self-administer nicotine, and over two weeks their nicotine intakes increased, suggesting addiction. Then, one group of rats was given the enzyme, which led to a decreased nicotine intake. The scientists say that the enzyme could be developed for human use in the future.
1.Which of the following best explains the underlined phrase “susceptible to” in paragraph 2?
A.Not likely to be cured of. B.Being disease-resistant to.
C.Very likely to be affected by. D.Being thoroughly exposed to.
2.What does the author intend to show in the third paragraph?
A.Rats in the city are particular about their food.
B.Rats in different cities have different genetic make-up.
C.Rats are distributed in every continent of the earth.
D.Rats have been adjusting themselves to the environment.
3.What is the purpose of testing an enzyme on rats?
A.To explore rats’ survival ability. B.To help people stop smoking.
C.To learn more about city rats. D.To tell apart nicotine and enzyme.
4.What is the best title of this text?
A.Rats Have Adapted to Modern Human Life
B.Rats in the City Have Varieties of Diets
C.Rats Are More Adaptable than Humans
D.Rats Have the Same Genetic Make-up to Humans
高三英语阅读理解中等难度题查看答案及解析
SCIENTISTS have discovered that living to the age of 100 may have nothing to do with the lifestyle you lead and everything to do with the type of genes (基因) you have.
For the lucky carriers of “Methuselah” genes, worries over smoking, eating unhealthily and not getting enough exercise may not be as necessary as to those of us without the special gene pattern .
The “Methuselah” genes could give extra protection against the diseases of old age such as cancer and heart disease. They could also protect people against the effects of the unhealthy lifestyles that we believe will lead us to an early death, scientists say. However, the genes are very rare.
The genes include ADIPOQ, which is found in about 10 percent of young people but in nearly 30 percent of people living past 100. They also include the CETP and the ApoC3 genes, which are found in 10 percent of young people, but in about 20 percent of people over 100 years old.
Some of those genes were discovered by a research group at the Albert Einstein College of Medicine in New York, led by Professor Nir Barzilai. The team studied the genes of over 500 people over 100 years old, and their children.
The studies show that tiny mutations (变异) in the make-up of some genes can greatly increase a person’s lifespan. Barzilai told a Royal Society conference that the discovery of such genes gave scientists clear targets for developing drugs that could prevent age-related diseases, allow people to live longer and stay healthy.
David Gems, a researcher at University College London, believes that drugs to slow ageing will become widespread.
“If we know which genes control longevity (长寿) then we can … target them with drugs. That makes it possible to slow down ageing,” he told The Times.
“Much of the pain and suffering in the world are caused by ageing. If we can find a way to reduce that, then we are obliged to take it.”
1. According to the article, which of the following is the most important if a person is to live to the age of 100?
A. Eating healthy food every day.
B. Having the right types of genes.
C. Having a healthy lifestyle.
D. Taking drugs that prevent ageing.
2.According to the article, the ApoC3 gene is found in ______ of people over 100 years old.
A. 10% B. 20% C. 30% D. 50%
3.Which of the following statements is TRUE of the research led by Professor Nir Barzilai?
A. The team studied the genes of over 100 people over 100 years of age.
B. The researchers found that mutations in certain genes lead to longer life.
C. The researchers found ways to develop drugs that could cure age-related diseases.
D. The study suggested that most people have genes that could lengthen their lives.
4. According to David Gems, ______.
A. drugs to slow ageing will be very expensive
B. modern science will be able to find more longevity genes
C. it is the duty of medical scientists to fight the problems of ageing
D. scientists can make new genes that will allow longer life
高三英语阅读理解中等难度题查看答案及解析
Scientists have discovered that living to the age of 100 may have nothing to do with the lifestyle you lead and everything to do with the type of genes you have.
For the lucky carriers of “Methuselah” genes, worries over smoking, eating unhealthily and not getting enough exercise may not be as necessary as to those of us without the special gene pattern. The “Methuselah” genes could give extra protection against the diseases of old age such as cancer and heart disease. They could also protect people against the effects of the unhealthy lifestyles that we believe will lead us to an early death, scientists say. However, the genes are very rare.
The genes include ADIPOQ, which is found in about 10 percent of young people but in nearly 30 percent of people living past 100. They also include the CETP and the ApoC3 genes, which are found in 10 percent of young people, but in about 20 percent of people over 100 years old.
Some of those genes were discovered by a research group at the Albert Einstein College of Medicine in New York, led by Professor Nir Barzilai. The team studied the genes of over 500 people over 100 years old, and their children.
The studies show that tiny mutations (变异) in the make-up of some genes can greatly increase a person’s lifespan. Barzilai told a Royal Society conference that the discovery of such genes gave scientists clear targets for developing drugs that could prevent age-related diseases, allow people to live longer and stay healthy.
David Gems, a researcher at University College London, believes that drugs to slow ageing will become widespread.
“If we know which genes control longevity (长寿) then we can... target them with drugs. That makes it possible to slow down ageing,” he told The Times.
“Much of the pain and suffering in the world are caused by ageing. If we can find a way to reduce that, then we are obliged to take it.”
1.Which genes could give extra protection against the diseases of old age? (No more than 3 words) (2 marks)
__________________________________________________________________________
2. Whom did Barzilai’s team study? (No more than 10 words) (2 marks)
__________________________________________________________________________
3. What can greatly increase a person’s lifespan? (No more than 10 words) (3 marks)
__________________________________________________________________________
4.What can scientists do if they are aware which genes control longevity?(No more than 6 words) (3 marks)
__________________________________________________________________________.
高三英语其他题中等难度题查看答案及解析
BEIJING - A research team led by Chinese scientists have discovered dietary modulation of gut microbiota(膳食干预肠道菌群)can alleviate both genetic and simple obesity in children.
The findings of the team, led by Zhao Liping with Shanghai Jiaotong University, Yin Aihua with the Guangdong province children's hospital, and Tang Huiru with Chinese Academy of Sciences, have been published on EBioMedicine, a renowned medical journal co-sponsored by Cell and The Lancet in July.
The team identified bacterial genomes specifically for producing obesity-related metabolites(代谢物), and said an improved gut microbiota can significantly help to treat genetic obesity such as Prader-Willi Syndrome (PWS).
Beginning in childhood, PWS affected kids develop an insatiable appetite, leading to chronic overeating and obesity.
The scientists used a diet therapy with beneficial gut bacteria on trial patients and found considerable diminished appetite, weight loss and improved health conditions on the patients.
The paper concluded dysbiosis (失调)of gut microbiota is highly related with both genetic and simple obesity in children, implicating dietary modulation of gut microbiota a potentially effective treatment method.
1. Which of the following factors contributes to child obesity?
A. dietary modulation of gut microbiota
B. beneficial gut bacteria
C. an improved gut microbiota
D. dysbiosis of gut microbiota
2. Which can replace the underlined word “diminished”?
A. unsatisfied B. increased
C. decreased D. good
3. Where is the passage extracted?
A. Medicine book B. Science book
C. Doctor’s instructions D. News report
4. Which might be the best title for the passage?
A. Chinese scientists discover treatment to child obesity.
B .The reasons for genetic obesity in children has been found.
C. Obesity-related research has been done by Chinese scientists.
D. An effective treatment to obesity has been found.
高三英语阅读理解中等难度题查看答案及解析
Scientists say they have discovered a promising treatment for sleeping sickness, a killer disease that infects(感染) about 60,000 people in Africa a year.
British and Canadian experts say drugs could attack the parasite(寄生虫) causing the illness needs to survive. They say the drug could be ready for human medical test in about 18 months.
The disease, spread by the bite of a fly, is caused by a parasite attacking the central nervous system. It has similar symptoms(症状) to malaria(疟疾), making it difficult to diagnose. Left untreated, it moves to the brain, resulting in mental confusion and final death
The "breakthrough" came at the University of Dundee in Scotland, where scientists were offered money to research diseases ignored by major drugs companies.
Professor Paul Wyatt, director of the programme, said: "This is one of the most significant findings made in recent years in terms of drug discovery and development for ignored diseases."
He said the research, published in the journal Nature, represented "significant progress" in the development of a full blown drug against the disease.
The World Health Organization said there are between 50,000 and 70,000 cases of the disease a year, with a further 60 million people at risk of infection.
The research in Dundee was backed by partners at the University of York in England and the Structural Genomics Consortium in Toronto, Canada. The two drugs currently available to treat sleeping sickness both have problems. One is with side effects that kill one in 20 patients and the other is costly, only partially effective and requires long-time hospital treatment, the scientists said.
1.The word backed in the last paragraph probably means_____.
A. conducted B. supported C. believed D. managed
2.What the World Health Organization said suggested that______.
A. about 60000 people died of the disease each year
B. about 60000 people were cured of the disease each year
C. 600 million people are likely to get infected
D. the disease is spreading fast in Africa
3.We can read this passage______.
A. in the journal Nature
B. in a newspaper of the University of Dundee
C. in a book about flies
D. in a newspaper about medicine
4.We can learn from the passage that______ .
A .big drug companies play an important role in the research of the new drug
B. people who get infected with the disease are mentally disturbed
C. among 200 people infected with the disease, 5 may die because of the old drug
D. Professor Paul Wyatt may be a professor at the University of York
高三英语阅读理解简单题查看答案及解析
Scientists at Royal Holloway, University of London and Queen Mary, University of London have discovered that bees learn to fly the shortest possible route between flowers even if they discover the flowers in a different order. Bees are effectively solving the “traveling salesman problem”, and they are the first creatures found to do this.
The traveling salesman must find the shortest route that allows him to visit all locations on his route. Computers solve it by comparing the length of all possible routes and choosing the shortest, and it can keep computers busy for days. However, bees solve it without computer assistance using a brain the size of grass seed. Dr. Nigel Raine, from the School of Biological Sciences at Royal Holloway explains, “Bees solve traveling salesman problems every day. They visit flowers at multiple locations and because bees use lots of energy to fly, they find a route which keeps flying to a minimum. ”
The team used the computer to control artificial flowers to test whether bees would follow a route defined by the order in which they discovered the flowers or if they would find the shortest route. After exploring the location of the flowers, bees quickly learned to fly the shortest route.
As well as improving our understanding of how bees move around the landscape pollinating(授粉)crops and wild flowers, this research, which is due to be published in The American Naturalist, has other applications. Our lifestyle relies on networks such as traffic on the roads, information flow on the Web and business supply chains. By understanding how bees can solve their problems with such a tiny brain, we can improve our management of these everyday networks without needing lots of computer time. Dr. Raine adds, “Despite their tiny brains, bees are capable of extraordinary feats of behavior. We need to understand how they can solve the traveling salesman problem without a computer. ”
1. What would be the best title of the passage?
A. Bees help salesmen travel
B. Tiny-brained bees solve a complex mathematical problem
C. How bees discover the flowers
D. How to solve the “traveling salesman problem”
2.We may infer from the second paragraph that the “traveling salesman problem” .
A. can be solved by a computer easily
B. can’t even be solved by a computer
C. can puzzle both people and computers
D. remains to be solved by scientists
3. The main purpose of the last paragraph is to .
A. provide further proof for the research
B. tell us how bees can fly the shortest route between flowers
C. tell us how the research about bees’ flying route was conducted
D. explain the importance of the research
4. It can be concluded from the passage that .
A. all creatures are smarter than computers
B. the research about bees’ flying route can be applied to many fields
C. our networks are more complex than bees’ ones
D. with the help of the computer we can find out how bees can solve the “traveling salesman problem”
高三英语阅读理解中等难度题查看答案及解析
Scientists have discovered thirteen kinds of vitamins. They say vitamins help to carry out chemical changes within cells. If we do not get enough of the vitamins we need in our food, we are at risk of developing a number of diseases. Which foods should be eaten to keep us healthy? Let us look at some important vitamins.
Vitamin A helps prevent skin and other tissues from becoming dry. People who do not get enough vitamin A cannot see well in darkness. Vitamin A is found in fish liver oil and the yellow part of eggs.
Vitamin B-1 is also called thiamine. Thiamine changes starchy(含淀粉的)foods into energy. Thiamine is found not just in whole grains like brown rice, but also in beans and peas, nuts, and meat and fish.
Vitamin B-12 is needed so folic acid can do its work. Together, they help produce red blood cells. Folic acid has been shown to prevent physical problems in babies when taken by their mothers during pregnancy. Vitamin B-12 is found naturally in foods like eggs, meat, fish and milk products. Vitamin B-12 is found in green leafy vegetables and other foods, like legumes and citrus fruits (柑橘类水果).
Vitamin C is needed for strong bones and teeth. The body stores little vitamin C. So we must get it every day in foods such as citrus fruits, tomatoes and uncooked cabbage.
Vitamin D prevents the children’s bone disease rickets (佝偻病). Ultraviolet light from the sun changes a substance in the skin into vitamin D. Fish liver oil also contains vitamin D.
Vitamin K is needed for healthy blood. It thickens the blood around a cut to stop bleeding. It can also be found in pork products, liver and in vegetables like cabbage, kale and spinach (菠菜).
Vitamins are important to our health. A lack of required vitamins can lead to health problems.
1.What is the main idea of the passage?
A. There are thirteen kinds of vitamins in total.
B. One can not live without enough vitamins.
C. Vitamins can carry out chemical changes within cells.
D. Enough vitamins are vital to keep healthy.
2.Women who wish to become mothers should take in ________.
A. vitamin A B. vitamin B-1
C. vitamin B-12 D. vitamin C
3.What can change a substance in the skin into vitamin D?
A. Fish liver oil.
B. Ultraviolet light from the sun.
C. Fresh milk drunk by people.
D. Doing a certain amount of exercise.
4.According to the passage, taking in enough vitamin C can ________.
A. make our eyesight better
B. help to stop bleeding
C. make our bones and teeth strong
D. help produce red blood cells
高三英语阅读理解中等难度题查看答案及解析
BEIJING - A research team led by Chinese scientists have discovered dietary modulation of gut microbiota(膳食干预肠道菌群)can alleviate both genetic and simple obesity in children.
The findings of the team, led by Zhao Liping with Shanghai Jiaotong University, Yin Aihua with the Guangdong province children's hospital, and Tang Huiru with Chinese Academy of Sciences, have been published on EBioMedicine, a renowned medical journal co-sponsored by Cell and The Lancet in July.
The team identified bacterial genomes specifically for producing obesity-related metabolites(代谢物), and said an improved gut microbiota can significantly help to treat genetic obesity such as Prader-Willi Syndrome (PWS).
Beginning in childhood, PWS affected kids develop an insatiable appetite, leading to chronic overeating and obesity.
The scientists used a diet therapy with beneficial gut bacteria on trial patients and found considerable diminished appetite, weight loss and improved health conditions on the patients.
The paper concluded dysbiosis(失调)of gut microbiota is highly related with both genetic and simple obesity in children, implicating dietary modulation of gut microbiota a potentially effective treatment method.
1.Which of the following factors contributes to child obesity ?
A. dietary modulation of gut microbiota
B. beneficial gut bacteria
C. an improved gut microbiota
D. dysbiosis of gut microbiota
2.Which can replace the underlined word “diminished”?
A. unsatisfied B. increased
C. decreased D. good
3.Where is the passage extracted?
A. Medicine book B. Science book
C. Doctor’s instructions D. News report
4.Which might be the best title for the passage?
A. Chinese scientists discover treatment to child obesity.
B.The reasons for genetic obesity in children has been found.
C. Obesity-related research has been done by Chinese scientists.
D. An effective treatment to obesity has been found.
高三英语阅读理解中等难度题查看答案及解析