- Câu hỏi 738348:
Read the text and choose the best answer.
In the 1940's and 1950's, biochemists strived to learn why each of the vitamins was essential for health. They discovered that key enzymes in metabolism depend on one or another of the vitamins as coenzymes to perform the chemistry that provides cells with energy for growth and function. Now, these enzyme hunters occupied center stage.
The word "strived" is closest in meaning to
A. experimented
B. tried
C. failed
D. studied
- Câu hỏi 738349:
Read the text and choose the best answer.
The World Wide Web, an enormous collection of Internet addresses or sites, all of which can be accessed for information, has been mainly responsible for the increase in interest in the Internet in the 1990s. Before the World Wide Web, the 'Net' was comparable to an integrated collection of computerised typewriters, but the introduction of the 'Web' in 1990 allowed not only text links to be made but also graphs, images and even video. A Web site consists of a 'home page', the first screen of a particular site on the computer to which you are connected, from where access can be had to other subject related 'pages' at the site and to thousands of other computers all over the world. This is achieved by a process called 'hypertext'. By clicking with a mouse device on various parts of the screen, a person connected to the 'Net' can go travelling, or 'surfing' through a web of pages to locate whatever information is required.
Which is the topic sentence of the paragraph?
A. Sentence number one
B. Sentence number two
C. the last sentence
D. Sentence number three
- Câu hỏi 113845:
Read the text and choose the best answer.
Almost everyone with or without a computer is aware of the latest technological revolution destined to change forever the way in which humans communicate, namely, the Information Superhighway, best exemplified by the ubiquitous Internet. Already, millions of people around the world are linked by computer simply by having a modem and an address on the 'Net', in much the same way that owning a telephone links us to almost anyone who pays a phone bill. In fact, since the computer connections are made via the phone line, the Internet can be envisaged as a network of visual telephone links. It remains to be seen in which direction the Information Superhighway is headed, but many believe it is the educational hope of the future.
The World Wide Web, an enormous collection of Internet addresses or sites, all of which can be accessed for information, has been mainly responsible for the increase in interest in the Internet in the 1990s. Before the World Wide Web, the 'Net' was comparable to an integrated collection of computerised typewriters, but the introduction of the 'Web' in 1990 allowed not only text links to be made but also graphs, images and even video. A Web site consists of a 'home page', the first screen of a particular site on the computer to which you are connected, from where access can be had to other subject related 'pages' at the site and to thousands of other computers all over the world. This is achieved by a process called 'hypertext'. By clicking with a mouse device on various parts of the screen, a person connected to the 'Net' can go travelling, or 'surfing' through a web of pages to locate whatever information is required.
Anyone can set up a site; promoting your club, your institution, your company's products or simply yourself, is what the Web and the Internet is all about. And what is more, information on the Internet is not owned or controlled by anyone organisation. It is, perhaps, true to say that no-one and therefore everyone owns the 'Net'. Because of the relative freedom of access to information, the Internet has often been criticised by the media as a potentially hazardous tool in the hands of young computer users. This perception has proved to be largely false however, and the vast majority of users both young and old get connected with the Internet for the dual purposes for which it was intended – discovery and delight.
Which is the best title for the passage ?
A. How to Use the Internet
B. The Educational Hope of the Future
C. The Internet Revolution
D. The World Wide Web
- Câu hỏi 113846:
Read the text and choose the best answer.
The first two decades of this century were dominated by the microbe hunters. These hunters had tracked down one after another of the microbes responsible for the most dreaded scourges of many centuries: tuberculosis, cholera, diphtheria. But there remained some terrible diseases for which no microbe could be incriminated: scurvy, pellagra, rickets, beriberi. Then it was discovered that these diseases were caused by the lack of vitamins, a trace substance in the diet. The diseases could be prevented or cured by consuming foods that contained the vitamins. And so in the decades of the 1920's and 1930's, nutrition became a science and the vitamin hunters replaced the microbe hunters.
In the 1940's and 1950's, biochemists strived to learn why each of the vitamins was essential for health. They discovered that key enzymes in metabolism depend on one or another of the vitamins as coenzymes to perform the chemistry that provides cells with energy for growth and function. Now, these enzyme hunters occupied center stage.
You are aware that the enzyme hunters have been replaced by a new breed of hunters who are tracking genes-the blueprints for each of the enzymes-and are discovering the defective genes that cause inherited diseases-diabetes, cystic fibrosis. These gene hunters, or genetic engineers, use recombinant DNA technology to identify and clone genes and introduce them into bacterial cells and plants to create factories for the massive production of hormones and vaccines for medicine and for better crops for agriculture. Biotechnology has become a multibillion-dollar industry.
In view of the inexorable progress in science, we can expect that the gene hunters will be replaced in the spotlight. When and by whom? Which kind of hunter will dominate the scene in the last decade of our waning century and in the early decades of the next? I wonder whether the hunters who will occupy the spotlight will be neurobiologists who apply the techniques of the enzyme and gene hunters to the functions of the brain. What to call them? The head hunters. I will return to them later.
What is the main topic of the passage?
A. The progress of modern medical research
B. The discovery of enzymes
C. The potential of genetic engineering
D. The microbe hunters
- Câu hỏi 113848:
Read the text and decide that the statement is TRUE (T), FALSE (F) or NOT GIVEN (NG).
When was the last time you saw a frog? Chances are, if you live in a city, you have not seen one for some time. Even in wet areas once teeming with frogs and toads, it is becoming less and less easy to find those slimy, hopping and sometimes poisonous members of the animal kingdom. All over the world, even in remote jungles on the far side of the globe, frogs are losing the ecological battle for survival, and biologists are at a loss to explain their demise. Are amphibians simply over-sensitive to changes in the ecosystem? Could their rapid decline in numbers be signalling some coming environmental disaster for us all?
Frogs and toads are usually poisonous.
- Câu hỏi 113849:
Read the text and choose the best answer.
Western people rely on technical and mechanical solutions in everything they do. Refrigerators preserve their food, washing machines clean their underwear and computers are supposed to solve all their problems. When they are ill, they rely on the surgeon’s knife. If their hearts are running down, then they must be repaired, if they cannot be repaired, they should be replaced, just as an old car sometimes gets a new engine. But up to now we have had a shortage of donors to give their hearts, to keep one person alive, another donor had to die.
Nowadays there is more and more talk about using monkeys. Every monkey has a near-human heart, and humans have always been over careful in respecting the lives and well-being of other animals. This includes the life and well-being of other humans. Therefore, in the early years of the 22nd century - It was told the mass killings of monkeys may occur. We’ll need to use their hearts for human consumption.
Monkeys, on the whole, are happier creatures than their near relatives, Homo sapiens, or man. They know fear, of course, and they face real dangers, but they are also more intelligent than us. They create no unnecessary dangers for themselves, they run no businesses, chase no money, are unimpressed by gold – that utterly useless metal, and they do not care at all about hell or evil spirits. I have a vague feeling that it is not monkeys’ hearts that we ought to implant in ourselves, but monkeys’ brains.
Monkeys are more stupid than humans because they always create unnecessary dangers for themselves…
A. TRUE
B. FALSE
C. NOT GIVEN
- Câu hỏi 113850:
Read the passage and answer the question.
Almost everyone with or without a computer is aware of the latest technological revolution destined to change forever the way in which humans communicate, namely, the Information Superhighway, best exemplified by the ubiquitous Internet. Already, millions of people around the world are linked by computer simply by having a modem and an address on the 'Net', in much the same way that owning a telephone links us to almost anyone who pays a phone bill. In fact, since the computer connections are made via the phone line, the Internet can be envisaged as a network of visual telephone links. It remains to be seen in which direction the Information Superhighway is headed, but many believe it is the educational hope of the future.
The World Wide Web, an enormous collection of Internet addresses or sites, all of which can be accessed for information, has been mainly responsible for the increase in interest in the Internet in the 1990s. Before the World Wide Web, the 'Net' was comparable to an integrated collection of computerised typewriters, but the introduction of the 'Web' in 1990 allowed not only text links to be made but also graphs, images and even video. A Web site consists of a 'home page', the first screen of a particular site on the computer to which you are connected, from where access can be had to other subject related 'pages' at the site and to thousands of other computers all over the world. This is achieved by a process called 'hypertext'. By clicking with a mouse device on various parts of the screen, a person connected to the 'Net' can go travelling, or 'surfing' through a web of pages to locate whatever information is required.
Anyone can set up a site; promoting your club, your institution, your company's products or simply yourself, is what the Web and the Internet is all about. And what is more, information on the Internet is not owned or controlled by anyone organisation. It is, perhaps, true to say that no-one and therefore everyone owns the 'Net'. Because of the relative freedom of access to information, the Internet has often been criticised by the media as a potentially hazardous tool in the hands of young computer users. This perception has proved to be largely false however, and the vast majority of users both young and old get connected with the Internet for the dual purposes for which it was intended – discovery and delight.
To what does pronoun "WHICH" in the passage refer?
A. Advertising on the World Wide Web
B. The Educational Hope of the Future
C. Internet addresses or sites
D. The Internet Revolution
- Câu hỏi 113866:
Read the text and choose the best answer.
The first two decades of this century were dominated by the microbe hunters. These hunters had tracked down one after another of the microbes responsible for the most dreaded scourges of many centuries: tuberculosis, cholera, diphtheria. But there remained some terrible diseases for which no microbe could be incriminated: scurvy, pellagra, rickets, beriberi. Then it was discovered that these diseases were caused by the lack of vitamins, a trace substance in the diet. The diseases could be prevented or cured by consuming foods that contained the vitamins. And so in the decades of the 1920's and 1930's, nutrition became a science and the vitamin hunters replaced the microbe hunters.
The word "which" refers to
A. microbe
B. cholera
C. diseases
D. diphtheria
- Câu hỏi 113868:
Read the article and choose the correct answer, A, B, C or D.
According to airline industry statistics, almost 90 percent of airline accidents are survivable or partially survivable. But passengers can increase their chances of survival by learning and following certain tips. Experts say that you should read and listen to safety instructions before takeoff and ask questions if you have uncertainties. You should fasten your seat-belt low on your hips and as tightly as possible. Of course, you should also know how the release mechanism of your belt operates. During takeoffs and landings, you are advised to keep your feet flat on the floor. Before takeoff you should locate the nearest exit and an alterative exit and count the rows of seats between you and the exits so that you can find them in the dark if necessary.
In the event that you are forewarned of a possible accident, you should put your hands on your ankles and keep your head down until the plane comes to a complete stop. If smoke is present in the cabin, you should keep your head low and cover your face with napkins, towels, or clothing. If possible, wet these for added protection against smoke inhalation. To evacuate as quickly as possible, follow crew commands and do not take personal belongings with you. Do not jump on escape slides before they are fully inflated, and when you jump, do so with your arms and legs extended in front of you. When you get to the ground, you should move away from the plane as quickly as possible, and never smoke near the wreckage.
It can be inferred from the passage that people are more likely to survive fires in aircrafts if they…
A. read airline safety statistics.
B. wear a safety belt.
C. don’t smoke in or near a plane.
D. keep their heads low.
- Câu hỏi 113880:
Read the text and decide that the statement is TRUE (T), FALSE (F) or NOT GIVEN (NG).
This frightening scenario is in part the consequence of a dramatic increase over the last quarter century in the development of once natural areas of wet marshland; home not only to frogs but to all manner of wildlife. Yet, there are no obvious reasons why certain frog species are disappearing from rainforests in the Southern Hemisphere which are barely touched by human hand. The mystery is unsett1ing to say the least, for it is known that amphibian species are extremely sensitive to environmental variations in temperature and moisture levels. The danger is that planet Earth might not only lose a vital link in the ecological food chain (frogs keep populations of otherwise pestilent insects at manageable levels), but we might be increasing our output of air pollutants to levels that may have already become irreversible. Frogs could be inadvertently warning us of a catastrophe.
There are many reasons why certain frog species are disappearing from rainforests in the Southern Hemisphere.