- Câu hỏi 113843:
Read the text and decide that the statement is True (T), False (F) or Not Given (NG).
Although the central region of Mexico's high plateau has been inhabited for at least 20,000 years, Mexico City only dates back to the 14th century. The Aztecs, or Mexica, had reached this area in the previous century, eventually settling on an island in Lake Texcoco. Here, in 1325, the city of Tenochtitlan began to take shape.
The lake was shallow, and during the nearly 200 years until 1519, the Aztecs expanded the inhabited area by land refill and the creation of artificial islands. Canals were dug for the transportation of goods and people. Aqueducts were constructed to bring drinking water from natural springs outside the city, dams to protect it against floods, and causeways and bridges to connect the city with the shore. There were many houses, palaces, temples, squares, markets and even a zoo. Perhaps the most striking construction of this period is the Templo Mayor, a double pyramid which still survives. As the capital of an empire stretching from Texas to Honduras, Tenochtitlan was a magnificent and important city. When the Spanish arrived, they called it the 'Venice of the New World'.
The area where people lived was artificially increased between 1325 and 1519.
- 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You are aware that the enzyme hunters have been replaced by a new breed of hunters who are tracking genes-the blueprints for each of the enzymes-and are discovering the defective genes that cause inherited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?
- Câu hỏi 113853:
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.
What is the main point of the first paragraph?
- Câu hỏi 113857:
Read the text and decide that the statement is TRUE (T), FALSE (F) or NOT GIVEN (NG).
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.
Everyone uses recombinant DNA technology to identify and clone genes.
- Câu hỏi 113862:
Read the text and choose the best answer.
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.
The word "them" refers to
- Câu hỏi 113871:
Read the text and choose the best answer.
One crucial development in this movement toward industrialization was the growth of the railroads. The railway network expanded rapidly until the railroad map of the looked like a spider's web, with the steel filaments connecting all important sources of raw materials, their places of manufacture, and their centers of distribution. The railroads contributed to the industrial growth not only by connecting these major centers, but also by themselves consuming enormous amounts of fuel, iron, and coal.
Many factors influenced emerging modes of production. For example, machine tools, the tools used to make goods, were steadily improved in the latter part of the nineteenth century-always with an eye to speedier production and lower unit costs. The products of the factories were rapidly absorbed by the growing cities that sheltered the workers and the distributors. The increased urban population was nourished by the increased farm production that, in turn, was made more productive by the use of the new farm machinery. American agricultural production kept up with the urban demand and still had surpluses for sale to the industrial centers of .
The labor that ran the factories and built the railways was recruited in part from American farm areas where people were being displaced by farm machinery, in part from Asia, and in part from . now began to send tides of immigrants from eastern and southern Europe-most of whom were originally poor farmers but who settled in American industrial cities. The money to finance this tremendous expansion of the American economy still came from European financiers for the most part, but the Americans were approaching the day when their expansion could be financed in their own "money market."
According to the passage, who were the biggest consumers of manufactured products?
- Câu hỏi 113872:
Read the text and answer the question.
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?
What does the pronoun their in the passage refer?
- Câu hỏi 113878:
Read the text and answer the question.
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.
What is best heading for the paragraph?
- Câu hỏi 113881:
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.
The problem with heart transplants has been that…
- Câu hỏi 113884:
Read the text and answer the question.
People appear to be born to compute. The numerical skills of children develop so early and so inexorably that it is easy to imagine an internal clock of mathematical maturity guiding their growth. Not long after learning to walk and talk, they can set the table with impressive accuracy — one plate, oneknife, one spoon, one fork, for each of the five chairs. Soon they are capable of noting that theyhave placed five knives, spoons, and forks on the table and, a bit later, that this amounts to fifteen pieces of silverware. Having thus mastered addition, they move on to subtraction. It seems almost reasonable to expect that if a child were secluded on a desert island at birth and retrieved seven years later, he or she could enter a second-grade mathematics class without any serious problems of intellectual adjustment.
Of course, the truth is not so simple. This century, the work of cognitive psychologists has illuminated the subtle forms of daily learning on which intellectual progress depends. Children were observed as they slowly grasped — or, as the case might be, bumped into — concepts that adults take for granted, as they refused, for instance, to concede that quantity is unchanged as water pours from a short stout glass into a tall thin one. Psychologists have since demonstrated that young children, asked to count the pencils in a pile, readily report the number of blue or red pencils, but must be coaxed into finding the total. Such studies have suggested that the rudiments of mathematics are mastered gradually, and with effort. They have also suggested that the very concept of abstract numbers — the idea of a oneness, a twoness, a threeness that applies to any class of objects and is a prerequisite for doing anything more mathematically demanding than setting a table — is itself far from innate.
With which of the following statements would the author be LEAST likely to agree?
