一．介紹。
二．做題準(zhǔn)備。
1． 詞匯、語(yǔ)法基礎(chǔ)。
2． 相關(guān)背景知識(shí)。
3． 整體和部分的關(guān)系。
三．答題步驟和做題技巧。
Passage 1
Stars in Their Eyes
The Scientific American Book of the Cosmos edited by David Levy, Macmillan, £20, ISBN 0333782933
Previous generations of scientists would have killed to know what we know. For the first time in history, we have a pretty good idea of the material content of the Universe, our position within it and how the whole thing came into being.
In these times of exploding knowledge there is a definite need to take stock and assemble what we know in a palatable（受歡迎的）form. ____________________ (41)
The essays in The Scientific American Book of the Cosmos have been selected by David Levy, co-discoverer of Comet Shoemaker-Levy 9, which in 1994 struck Jupiter with the violence of several full-scale nuclear wars. ____________________ (42) This is certainly a great collection of essays, but it is not, as the book promises, a seamless (完美的) synthesis of our current knowledge.
Nobody can fault the range of articles Levy has included. There are essays on the planets, moons and assorted debris (碎片) in the Solar System, and on our Galaxy, the Milky Way. ____________________ (43)
The contributions, too, are stars in their own fields. Not many books can boast chapters written by such giants as Erwin Schrodinger and Francis Crick. My personal favorites are a piercingly clear essay by Albert Einstein on general relativity and an article by Alan Guth and Paul Steinhardt on the inflationary Universe.
So much for the book’s content. But levy has not succeeded in providing an accurate synthesis of our current knowledge of the cosmos, which the book jacket promises. Gathering together previously published articles inevitably leaves subject gaps, missing explanations and so on. ____________________ (44) But there isn’t one. In fact surprisingly for a book so densely packed with information, there is no index.
Collecting essays in this way is clearly a good publishing wheeze. But this approach shortchanges the public, who would be better served by an account molded into a seamless whole. ____________________ (45) However, for the next edition, please, please can we have an index?
[A] Tegmark fears he may hold the record for the longest time taken to read one book.
[B] In a more positive vein, this is a wonderful collection of essays to dip in and out of if you already have a good overview of current cosmos understanding.
[C] Levy is an active astronomer and an accomplished writer, so you’d expect him to provide a broad and accurate picture of our current understanding of the cosmos.
[D] Scientific American has attempted to cater to this need by bringing together essays that have appeared in the magazine.
[E] To some extent, these could have been plugged with a glossary of terms.
[F] Also included are contributions on the world of subatomic particles, the origin of life on Earth and the possibility of its existence elsewhere.
Passage 2
Inca society was strictly organized, from the emperor and royal family down to the peasants. The emperor was thought to be descended from the sun god, Inti, and he therefore ruled with divine authority. All power rested in his hands. Only the influence of custom and the fear of revolt checked the emperor’s power. (41) __________. The emperor chose his most important administrators from among his sons.
Just below the emperor came the aristocracy, which included descendants and relations of all the emperors. (42) __________. The nobles of conquered peoples also became part of the governing aristocracy and were considered Inca by adoption.
For administrative purposes the empire was divided into regions known as the “four suyus (quarters) of the world,” with Cuzco at its center. The Incas called their empire “Land of the Four Quarters.” One suyu, the Antisuyu, stretched to the east of Cuzco and contained deep, forest-covered valleys that gradually descended into the jungles of the Amazon basin. Indian groups in this region, many of whom were only partially pacified, continued to launch attacks against the Incas. Cuntisuyu included all the land west of Cuzco, including the coastal regions of Peru from Chan Chan to Arequipa. Collasuyu was the largest of the quarters. Located south of Cuzco, it took in Lake Titicaca and regions of Bolivia, Chile, and Argentina. Chincasuyu contained the remaining land to the north of Cuzco.
A blood relative of the emperor served as governor of each quarter. The Incas further divided each quarter into progressively smaller units, with officials of descending rank overseeing the activities of these units. (43) __________. Another official, ideally a leader of a large village, ruled over a smaller area containing about 1,000 peasants. At the level below, ten foremen each supervised a total of 100 peasants. At the lowest organizational level, an official oversaw a group of ten peasants. For every 10,000 people, there were 1,331 officials.
Inca state affairs were complex and tightly controlled. Whole native populations were at times uprooted and resettled in other communities. Often groups were relocated to areas where they were needed for agricultural or mining activities. Sometimes relocations were politically motivated. (44) __________. Furthermore, these relocations facilitated the spread of Inca ideas and culture and promoted unity in the empire.
In order to deal efficiently with such matters, government officers kept strict accounts of all the people, gold, land, crops and projects of the empire. Since the Incas had no system of writing, they kept records by means of a quipu—a series of short, knotted strings hung at intervals from a long top string. By varying the colors and kinds of string used and the spacing of the strings and knots, the Incas could record populations, troops, and tribute, as well as information about their legends and achievements. The quipu was a complex memory aid rather than a literal record, and only a trained quipucamayo, or memory expert, could create or interpret it. An oral comment accompanied each quipu and allowed the quipucamayo to make sense of its meaning. (45) __________. Modern scholars still have not deciphered the codes used in the creation of quipus.
[A] Serving under each governor were ten district governors, each of whom ruled over a district containing about 10,000 peasants.
[B] Following the Spanish conquest and the introduction of records written in Spanish, the Incas lost the ability to read quipus.
[C] Noticeable economic thriving was frequently found, in the records of the local governments, after relocations.
[D] The emperor had one official wife, but he had many royal concubines and his children by these wives often numbered in the hundreds.
[E] Placing Quechua-speaking populations in newly conquered areas impaired the ability of local groups to unite against the Incas.
[F] Relations between relatives of the emperor, governors and officials often posed headaches for the supreme ruler himself, who was interwoven tightly and deeply among them.
[G] These pure-blooded Incas held the most important government, religious, and military posts.
Passage 3
Long before Man lived on the Earth, there were fishes, reptiles, birds, insects, and some mammals. Although some of these animals were ancestors of kinds living today, others are now extinct, that is, they have no descendants alive now. 41) __________.
Very occasionally the rocks show impression of skin, so that, apart from color, we can build up a reasonably accurate picture of an animal that died millions of years ago. The kind of rock in which the remains are found tells us much about the nature of the original land, often of the plants that grew on it, and even of its climate.
42) __________. Nearly all of the fossils that we know were preserved in rocks formed by water action, and most of these are of animals that lived in or near water. Thus it follows that there must be many kinds of mammals, birds, and insects of which we know nothing.
43) __________. There were also crab-like creatures, whose bodies were covered with a horny substance. The body segments each had two pairs of legs, one pair for walking on the sandy bottom, the other for swimming. The head was a kind of shield with a pair of compound eyes, often with thousands of lenses. They were usually an inch or two long but some were 2 feet.
44) __________. Of these, the ammonites are very interesting and important. They have a shell composed of many chambers, each representing a temporary home of the animal. As the young grew larger it grew a new chamber and sealed off the previous one. Thousands of these can be seen in the rocks on the Dorset Coast.
45) __________.
About 75 million years ago the Age of Reptiles was over and most of the groups died out. The mammals quickly developed, and we can trace the evolution of many familiar animals such as the elephant and horse. Many of the later mammals, though now extinct, were known to primitive man and were featured by him in cave paintings and on bone carvings.
[A] The shellfish have a long history in the rock and many different kinds are known.
[B] Nevertheless, we know a great deal about many of them because their bones and shells have been preserved in the rocks as fossils. From them we can tell their size and shape, how they walked, the kind of food they ate.
[C] The first animals with true backbones were the fishes, first known in the rocks of 375 million years ago. About 300 million years ago the amphibians, the animals able to live both on land and in water, appeared. They were giant, sometimes 8 feet long, and many of them lived in the swampy pools in which our coal seam, or layer, was formed. The amphibians gave rise to the reptiles and for nearly 150 million years these were the principal forms of life on land, in the sea, and in the air.
[D] The best index fossils tend to be marine creatures. These animals evolved rapidly and spread over large areas of the world.
[E] The earliest animals whose remains have been found were all very simple kinds and lived in the sea. Later forms are more complex, and among these are the sea-lilies, relations of the starfishes, which had long arms and were attached by a long stalk to the sea bed, or to rocks.
[F] When an animal dies, the body, its bones, or shell, may often be carried away by streams into lakes or the sea and there get covered up by mud. If the animal lived in the sea its body would probably sink and be covered with mud. More and more mud would fall upon it until the bones or shell become embedded and preserved.
[G] Many factors can influence how fossils are preserved in rocks. Remains of an organism may be replaced by minerals, dissolved by an acidic solution to leave only their impression, or simply reduced to a more stable form.
附錄：科學(xué)分支
BRANCHES OF SCIENCE
Classifying sciences involves arbitrary decisions because the universe is not easily split into separate compartments. This article divides science into five major branches: mathematics, physical sciences, earth sciences, life sciences, and social sciences. A sixth branch, technology, draws on discoveries from all areas of science and puts them to practical use. Each of these branches itself consists of numerous subdivisions. Many of these subdivisions, such as astrophysics or biotechnology, combine overlapping disciplines, creating yet more areas of research.
A Mathematical Sciences 數(shù)學(xué)
The mathematical sciences investigate the relationships between things that can be measured or quantified in either a real or abstract form. Pure mathematics differs from other sciences because it deals solely with logic, rather than with nature's underlying laws. However, because it can be used to solve so many scientific problems, mathematics is usually considered to be a science itself.
Central to mathematics is arithmetic算術(shù), the use of numbers for calculation. In arithmetic, mathematicians combine specific numbers to produce a result. A separate branch of mathematics, called algebra代數(shù)學(xué), works in a similar way, but uses general expressions that apply to numbers as a whole. For example, if there are three separate items on a restaurant bill, simple arithmetic produces the total amount to be paid. But the total can also be calculated by using an algebraic formula. A powerful and flexible tool, algebra enables mathematicians to solve highly complex problems in every branch of science.
Geometry 幾何學(xué) investigates objects and the spaces around them. In its simplest form, it deals with objects in two or three dimensions, such as lines, circles, cubes, and spheres. Geometry can be extended to cover abstractions, including objects in many dimensions. Although we cannot perceive these extra dimensions ourselves, the logic of geometry still holds.
In geometry, it is easy to work out the exact area of a rectangle or the gradient (slope) of a line, but there are some problems that geometry cannot solve by conventional means. For example, geometry cannot calculate the exact gradient at a point on a curve, or the area that the curve bounds. Scientists find that calculating quantities like this helps them understand physical events, such as the speed of a rocket at any particular moment during its acceleration.
To solve these problems, mathematicians use calculus微積分學(xué), which deals with continuously changing quantities, such as the position of a point on a curve. Its simultaneous development in the 17th century by English mathematician and physicist Isaac Newton and German philosopher and mathematician Gottfried Willhelm Leibniz enabled the solution of many problems that had been insoluble by the methods of arithmetic, algebra, and geometry. Among the advances that calculus helped develop were the determination of Newton’s laws of motion and the theory of electromagnetism.
B Physical Sciences 自然科學(xué)
The physical sciences investigate the nature and behavior of matter and energy on a vast range of size and scale. In physics itself, scientists study the relationships between matter, energy, force, and time in an attempt to explain how these factors shape the physical behavior of the universe. Physics can be divided into many branches. Scientists study the motion of objects, a huge branch of physics known as mechanics機(jī)械學(xué)、力學(xué) that involves two overlapping sets of scientific laws. The laws of classical mechanics經(jīng)典力學(xué) govern the behavior of objects in the macroscopic world, which includes everything from billiard balls to stars, while the laws of quantum mechanics量子力學(xué) govern the behavior of the particles that make up individual atoms.
Nobody really understands quantum physics, says scientist John Gribbin. Even to advanced physicists, the question of why subatomic particles can act as both waves and particles is still a puzzle. But the classic 19th-century “experiment with two holes” is still the best way to illustrate how they behave that way. Gribbin’s simple explanation of the experiment illuminates why quantum mechanics, which provides the basis for modern physics and the scientific understanding of the structure of matter, still challenges common sense.
Other branches of physics focus on energy and its large-scale effects. Thermodynamics熱力學(xué) is the study of heat and the effects of converting heat into other kinds of energy. This branch of physics has a host of highly practical applications because heat is often used to power machines. Physicists also investigate electrical energy and energy that is carried in electromagnetic waves. These include radio waves, light rays, and X rays—forms of energy that are closely related and that all obey the same set of rules.
(DNA脫氧核糖核酸 Strands. Nucleic acids核酸 are complex molecules produced by living cells and are essential to all living organisms. These acids govern the body’s development and specific characteristics by providing hereditary information and triggering the production of proteins within the body.)
Chemistry化學(xué) is the study of the composition of matter and the way different substances interact—subjects that involve physics on an atomic scale. In physical chemistry, chemists study the way physical laws govern chemical change, while in other branches of chemistry the focus is on particular chemicals themselves. For example, inorganic chemistry無(wú)機(jī)化學(xué) investigates substances found in the nonliving world and organic chemistry有機(jī)化學(xué) investigates carbon-based substances. Until the 19th century, these two areas of chemistry were thought to be separate and distinct, but today chemists routinely produce organic chemicals from inorganic raw materials. Organic chemists have learned how to synthesize many substances that are found in nature, together with hundreds of thousands that are not, such as plastics and pesticides. Many organic compounds, such as reserpine, a drug used to treat hypertension, cost less to produce by synthesizing from inorganic raw materials than to isolate from natural sources. Many synthetic medicinal compounds can be modified to make them more effective than their natural counterparts, with less harmful side effects.
The branch of chemistry known as biochemistry生物化學(xué) deals solely with substances found in living things. It investigates the chemical reactions that organisms use to obtain energy and the reactions they use to build themselves up. Increasingly, this field of chemistry has become concerned not simply with chemical reactions themselves but also with how the shape of molecules influences the way they work. The result is the new field of molecular biology分子生物學(xué)—one of the fastest-growing sciences today.
(Hubble Photo of Galaxy M100. In 1924 American astronomer Edwin Hubble showed that fuzzy patches in the sky called “spiral nebulas” were in fact galaxies like our Milky Way. The orbiting telescope named after him, the Hubble Space Telescope, took the picture of a distant galaxy called M100 in 1995.)
(Models of the Universe. According to the widely accepted theory of the big bang, the universe originated between 10 and 20 billion years ago and has been expanding ever since. Three models are commonly considered to model the future of the universe: a closed model, in which the expansion is finite, and the universe will eventually contract back in upon itself; an open model, in which the universe will continue expanding forever; and a flat model, in which the universe will not collapse upon itself, but also will not get larger and larger forever.)
Physical scientists also study matter elsewhere in the universe, including the planets and stars. Astronomy 天文學(xué) is the science of the heavens in general, while astrophysics天體物理學(xué) is a branch of astronomy that investigates the physical and chemical nature of stars and other objects. Astronomy deals largely with the universe as it appears today, but a related science called cosmology宇宙生成學(xué) looks back in time to answer the greatest scientific questions of all: how the universe began and how it came to be as it is today. (Stephen Hawking; Big Bang)
C Earth Sciences地球?qū)W
(Fossilized Footprints: Although the fossilized remains of dinosaurs are fairly common, their footprints, called trace fossils, are only occasionally found. Such fossils began as footprints in soft mud or clay that eventually hardened in the hot sun. Following hardening these impressions were covered over with fresh mud, sand, or clay during floods and eventually fossilized. Careful examination of such fossilized tracks can reveal useful information about the biology and general movements of dinosaurs.)
(Ocean Life and Resources: A rich variety of resources, both organic and inorganic, exists below the surface of the sea. Estimates indicate that the ocean is capable of producing as much as 200 million metric tons of harvestable organic matter and may contain more than 10 billion tons of gold. The only difficulty in tapping these resources is the complex interrelationship between the chemistry, geology, and physics of the sea. It is nearly impossible to alter one without impacting the others.)
The earth sciences examine the structure and composition of our planet, and the physical processes that have helped to shape it. Geology地質(zhì)學(xué) focuses on the structure of Earth, while geography地理學(xué) is the study of everything on the planet's surface, including the physical changes that humans have brought about from, for example, farming, mining, or deforestation. Scientists in the field of geomorphology地形學(xué) study Earth's present landforms, while mineralogists礦物學(xué)者 investigate the minerals in Earth's crust and the way they formed.
Water dominates Earth's surface, making it an important subject for scientific research. Oceanographers海洋學(xué)者 carry out research in the oceans, while scientists working in the field of hydrology水文學(xué) investigate water resources on land, a subject of vital interest in areas prone to drought. Glaciologists冰河學(xué)家 study Earth's icecaps and mountain glaciers, and the effects that ice has when it forms, melts, or moves. In atmospheric science, meteorology氣象學(xué) deals with day-to-day changes in weather, but climatology氣候?qū)W investigates changes in weather patterns over the longer term.
(Launching Ozone Balloon: Antarctica Earth scientists launch a balloon from the roof of a building at McMurdo research base in Antarctica. The balloon will be used to study Earth’s ozone layer.)
When living things die their remains are sometimes preserved, creating a rich store of scientific information. Paleontology古生物學(xué) is the study of plant and animal remains that have been preserved in sedimentary rock, often millions of years ago. Paleontologists study things long dead and their findings shed light on the history of evolution and on the origin and development of humans. A related science, called palynology孢粉學(xué), is the study of fossilized spores and pollen grains. Scientists study these tiny structures to learn the types of plants that grew in certain areas during Earth’s history, which also helps identify what Earth’s climates were like in the past.
D Life Sciences生命科學(xué)
(Cells細(xì)胞: The word cell refers to several types of organisms. Cells such as paramecia, dinoflagellates, diatoms, and spirochetes are self-maintaining organisms; cells such as lymphocytes, erythrocytes, muscle cells, nerve cells, cardiac muscle, and chloroplasts are more specialized cells that are a part of higher multicellular organisms. Regardless of size or whether the cell is a complete organism or just part of an organism, all cells have certain structural components in common. All cells have some type of outer cell boundary that permits some materials to leave and enter the cell and a cell interior composed of a water-rich, fluid material called cytoplasm that contains hereditary material in the form of deoxyribonucleic acid (DNA).
Erythrocytes紅血球: Erythrocytes, or red blood cells, are the primary carriers of oxygen to the cells and tissues of the body. The biconcave shape of the erythrocyte is an adaptation for maximizing the surface area across which oxygen is exchanged for carbon dioxide. Its shape and flexible plasma membrane allow the erythrocyte to penetrate the smallest of capillaries.
Smooth Muscle平滑肌: Human smooth muscle, also referred to as visceral or involuntary muscle, is composed of slender, spindle-shaped cells. Controlled by the autonomic nervous system, smooth muscle cells help form the structure of the skin, blood vessels, and internal organs.
Cardiac Muscle心肌: Cardiac muscle is a unique muscle tissue found only in the heart. Requiring a constant supply of oxygen, cardiac muscle will quickly die if obstructions occur in the arteries leading to the heart. Heart attacks occur from the damage caused by insufficient blood supply to cardiac muscle.
Nerve Cells神經(jīng)元,神經(jīng)細(xì)胞: The central cell body is clearly visible in each of the cells, as are the dendrites. The dendrites are short extensions of the nerve cell body that function in the reception of stimuli.
Spirochete Bacteria螺旋菌, which are included within the kingdom Prokaryotae, are single-celled organisms lacking a well-defined internal cellular organization.
Chloroplasts葉綠體: An examination of leaves, stems, and other types of plant tissue reveals the presence of tiny green, spherical structures called chloroplasts, visible here in the cells of an onion. Chloroplasts are essential to the process of photosynthesis, in which captured sunlight is combined with water and carbon dioxide in the presence of the chlorophyll molecule to produce oxygen and sugars that can be used by animals. Without the process of photosynthesis, the atmosphere would not contain enough oxygen to support animal life.)
The life sciences include all those areas of study that deal with living things. Biology生物學(xué) is the general study of the origin, development, structure, function, evolution, and distribution of living things. Biology may be divided into botany植物學(xué), the study of plants; zoology動(dòng)物學(xué), the study of animals; and microbiology微生物學(xué), the study of the microscopic organisms, such as bacteria, viruses, and fungi. Many single-celled organisms play important roles in life processes and thus are important to more complex forms of life, including plants and animals.
Genetics遺傳學(xué) is the branch of biology that studies the way in which characteristics are transmitted from an organism to its offspring. In the latter half of the 20th century, new advances made it easier to study and manipulate genes at the molecular level, enabling scientists to catalog all the genes found in each cell of the human body. Exobiology外空生物學(xué), a new and still speculative field, is the study of possible extraterrestrial life. Although Earth remains the only place known to support life, many believe that it is only a matter of time before scientists discover life elsewhere in the universe.
While exobiology is one of the newest life sciences, anatomy解剖學(xué) is one of the oldest. It is the study of plant and animal structures, carried out by dissection or by using powerful imaging techniques. Gross anatomy大體解剖學(xué) deals with structures that are large enough to see, while microscopic anatomy顯微解剖學(xué) deals with much smaller structures, down to the level of individual cells.
Correcting Genetic Diseases: Gene therapy基因療法 may someday be able to cure hereditary diseases, such as hemophilia and cystic fibrosis, which are caused by missing or defective genes. In one type of gene therapy, genetically engineered viruses are used to insert new, functioning genes into the cells of people who are unable to produce certain hormones or proteins necessary for the body to function normally.
Ecosystem生態(tài)系統(tǒng): The illustration presents a simplified ecosystem, or a community of interacting living and nonliving things. Producers, consumers, decomposers, and abiotic matter form an integrated, functioning whole driven by the Sun’s energy.
Physiology生理學(xué) explores how living things work. Physiologists study processes such as cellular respiration and muscle contraction, as well as the systems that keep these processes under control. Their work helps to answer questions about one of the key characteristics of life—the fact that most living things maintain a steady internal state when the environment around them constantly changes.
Together, anatomy and physiology form two of the most important disciplines in medicine醫(yī)學(xué), the science of treating injury and human disease. General medical practitioners have to be familiar with human biology as a whole, but medical science also includes a host of clinical specialties. They include sciences such as cardiology心(臟)病學(xué), urology泌尿?qū)W, and oncology腫瘤學(xué), which investigate particular organs and disorders, and also pathology病理學(xué), the general study of disease and the changes that it causes in the human body.
(Greenhouse Research: The controlled environment of a greenhouse provides an ideal setting for plant research.)
As well as working with individual organisms, life scientists also investigate the way living things interact. The study of these interactions, known as ecology生態(tài)學(xué), has become a key area of study in the life sciences as scientists become increasingly concerned about the disrupting effects of human activities on the environment.
E Social Sciences社會(huì)科學(xué)
(Footprints: From the Past In 1978 in Laetoli, Tanzania, a research team led by British paleoanthropologist Mary Leakey discovered these 3.6-million-year-old human footprints preserved in a layer of hardened volcanic ash. Two early humans of the species Australopithecus afarensis left the footprints as they walked across the African savanna. )
The social sciences explore human society past and present, and the way human beings behave. They include sociology社會(huì)學(xué), which investigates the way society is structured and how it functions, as well as psychology心理學(xué), which is the study of individual behavior and the mind. Social psychology社會(huì)心理學(xué) draws on research in both these fields. It examines the way society influences people's behavior and attitudes.
(Origins of Anthropology The modern study of anthropology had its origins in the European exploration and colonization of lands in the Americas, Asia, Africa, and the Pacific. European contacts with vastly different peoples sparked an interest in understanding and explaining human diversity, the goals of anthropology. )
Another social science, anthropology人類學(xué), looks at humans as a species and examines all the characteristics that make us what we are. These include not only how people relate to each other but also how they interact with the world around them, both now and in the past. As part of this work, anthropologists often carry out long-term studies of particular groups of people in different parts of the world. This kind of research helps to identify characteristics that all human beings share and those that are the products of local culture, learned and handed on from generation to generation.
The social sciences also include political science政治學(xué), law法學(xué), and economics經(jīng)濟(jì)學(xué), which are products of human society. Although far removed from the world of the physical sciences, all these fields can be studied in a scientific way. Political science and law are uniquely human concepts, but economics has some surprisingly close parallels with ecology. This is because the laws that govern resource use, productivity, and efficiency do not operate only in the human world, with its stock markets and global corporations, but in the nonhuman world as well.
F Technology技術(shù)
（Suspension Bridge吊橋: Civil engineers construct suspension bridges in areas where building a bridge with mid-span supports would be either extremely difficult or overly expensive. The span hangs from two enormous main cables, eliminating the need to bolster the bridge from underneath. The Clifton Suspension Bridge, completed in 1864, spans the Avon Gorge in Bristol, England.）
（Wind Tunnel風(fēng)洞: A wind tunnel is used to test the aerodynamic efficiency of an automobile. Streamlined body designs can greatly reduce the drag forces on moving objects such as automobiles or airplanes.）
In technology, scientific knowledge is put to practical ends. This knowledge comes chiefly from mathematics and the physical sciences, and it is used in designing machinery, materials, and industrial processes. In general, this work is known as engineering工程學(xué), a word dating back to the early days of the Industrial Revolution, when an "engine" was any kind of machine.
（Computer-Aided Design計(jì)算機(jī)輔助設(shè)計(jì) of Jet Engine: The plans for this jet turbine engine were created with computer-aided design (CAD) software. Engineers can check the architectural details, slicing through any section of the engine’s computer-generated blueprint or viewing it from any angle.）
Engineering has many branches, calling for a wide variety of different skills. For example, aeronautical engineers need expertise in the science of fluid flow, because airplanes fly through air, which is a fluid. Using wind tunnels and computer models, aeronautical engineers strive to minimize the air resistance generated by an airplane, while at the same time maintaining a sufficient amount of lift. Marine engineers also need detailed knowledge of how fluids behave, particularly when designing submarines that have to withstand extra stresses when they dive deep below the water’s surface. In civil engineering, stress calculations ensure that structures such as dams and office towers will not collapse, particularly if they are in earthquake zones. In computing, engineering takes two forms: hardware design and software design. Hardware design refers to the physical design of computer equipment (hardware). Software design is carried out by programmers who analyze complex operations, reducing them to a series of small steps written in a language recognized by computers.
（Genetic Engineering基因工程: Genetic engineering enables scientists to produce clones無(wú)性繁殖, 克隆 of cells or organisms that contain the same genes. 1. Scientists use restriction enzymes酶 to isolate a segment of deoxyribonucleic acid (DNA) 脫氧核糖核酸 that contains a gene of interest—for example, the gene regulating insulin production. 2. A plasmid extracted from a bacterium and treated with the same restriction enzyme can hybridize with this fragment’s “sticky” ends of complementary DNA. 3. The hybrid plasmid is reincorporated into the bacterium, where it replicates as part of the cell’s DNA. 4. A large number of identical daughter cells (clones) can be cultured and their gene products extracted for human use.）
In recent years, a completely new field of technology has developed from advances in the life sciences. Known as biotechnology生物工藝學(xué), it involves such varied activities as genetic engineering, the manipulation of genetic material of cells or organisms, and cloning, the formation of genetically uniform cells, plants, or animals. Although still in its infancy, many scientists believe that biotechnology will play a major role in many fields, including food production, waste disposal, and medicine.
Artificial Intelligence (AI)人工智能, a term that in its broadest sense would indicate the ability of an artifact to perform the same kinds of functions that characterize human thought. The possibility of developing some such artifact has intrigued human beings since ancient times. With the growth of modern science, the search for AI has taken two major directions: psychological and physiological research into the nature of human thought, and the technological development of increasingly sophisticated computing systems. In the latter sense, the term AI has been applied to computer systems and programs capable of performing tasks more complex than straightforward programming, although still far from the realm of actual thought. The most important fields of research in this area are information processing, pattern recognition, game-playing computers, and applied fields such as medical diagnosis. Current research in information processing deals with programs that enable a computer to understand written or spoken information and to produce summaries, answer specific questions, or redistribute information to users interested in specific areas of this information. Essential to such programs is the ability of the system to generate grammatically correct sentences and to establish linkages between words, ideas, and associations with other ideas. Research has shown that whereas the logic of language structure—its syntax—submits to programming, the problem of meaning, or semantics, lies far deeper, in the direction of true AI. Many scientists remain doubtful that true AI can ever be developed. The operation of the human mind is still little understood, and computer design may remain essentially incapable of analogously duplicating those unknown, complex processes. Various routes are being used in the effort to reach the goal of true AI. One approach is to apply the concept of parallel processing—interlinked and concurrent computer operations. Another is to create networks of experimental computer chips, called silicon neurons, that mimic data-processing functions of brain cells. Using analog technology, the transistors in these chips emulate nerve-cell membranes in order to operate at the speed of neurons.
Network（網(wǎng)絡(luò)）: techniques, physical connections, and computer programs used to link two or more computers. Network users are able to share files, printers, and other resources; send electronic messages; and run programs on other computers. A network has three layers of components: application software, network software, and network hardware. A network has two types of connections: physical connections that let computers directly transmit and receive signals and logical, or virtual, connections that allow computer applications, such as word processors, to exchange information. The wide use of notebook and other portable computers drives advances in wireless networks（無(wú)線網(wǎng)絡(luò)）. Wireless networks use either infrared or radio frequency transmissions to link these mobile computers to networks. Infrared wireless LANs work only within a room, while wireless LANs based on radio-frequency transmissions can penetrate most walls. If it can be integrated into a network, this new technology will make it easy, inexpensive, and incredibly fast to send information, such as video and memory-sensitive three-dimensional images.
二．做題準(zhǔn)備。
1． 詞匯、語(yǔ)法基礎(chǔ)。
2． 相關(guān)背景知識(shí)。
3． 整體和部分的關(guān)系。
三．答題步驟和做題技巧。
Passage 1
Stars in Their Eyes
The Scientific American Book of the Cosmos edited by David Levy, Macmillan, £20, ISBN 0333782933
Previous generations of scientists would have killed to know what we know. For the first time in history, we have a pretty good idea of the material content of the Universe, our position within it and how the whole thing came into being.
In these times of exploding knowledge there is a definite need to take stock and assemble what we know in a palatable（受歡迎的）form. ____________________ (41)
The essays in The Scientific American Book of the Cosmos have been selected by David Levy, co-discoverer of Comet Shoemaker-Levy 9, which in 1994 struck Jupiter with the violence of several full-scale nuclear wars. ____________________ (42) This is certainly a great collection of essays, but it is not, as the book promises, a seamless (完美的) synthesis of our current knowledge.
Nobody can fault the range of articles Levy has included. There are essays on the planets, moons and assorted debris (碎片) in the Solar System, and on our Galaxy, the Milky Way. ____________________ (43)
The contributions, too, are stars in their own fields. Not many books can boast chapters written by such giants as Erwin Schrodinger and Francis Crick. My personal favorites are a piercingly clear essay by Albert Einstein on general relativity and an article by Alan Guth and Paul Steinhardt on the inflationary Universe.
So much for the book’s content. But levy has not succeeded in providing an accurate synthesis of our current knowledge of the cosmos, which the book jacket promises. Gathering together previously published articles inevitably leaves subject gaps, missing explanations and so on. ____________________ (44) But there isn’t one. In fact surprisingly for a book so densely packed with information, there is no index.
Collecting essays in this way is clearly a good publishing wheeze. But this approach shortchanges the public, who would be better served by an account molded into a seamless whole. ____________________ (45) However, for the next edition, please, please can we have an index?
[A] Tegmark fears he may hold the record for the longest time taken to read one book.
[B] In a more positive vein, this is a wonderful collection of essays to dip in and out of if you already have a good overview of current cosmos understanding.
[C] Levy is an active astronomer and an accomplished writer, so you’d expect him to provide a broad and accurate picture of our current understanding of the cosmos.
[D] Scientific American has attempted to cater to this need by bringing together essays that have appeared in the magazine.
[E] To some extent, these could have been plugged with a glossary of terms.
[F] Also included are contributions on the world of subatomic particles, the origin of life on Earth and the possibility of its existence elsewhere.
Passage 2
Inca society was strictly organized, from the emperor and royal family down to the peasants. The emperor was thought to be descended from the sun god, Inti, and he therefore ruled with divine authority. All power rested in his hands. Only the influence of custom and the fear of revolt checked the emperor’s power. (41) __________. The emperor chose his most important administrators from among his sons.
Just below the emperor came the aristocracy, which included descendants and relations of all the emperors. (42) __________. The nobles of conquered peoples also became part of the governing aristocracy and were considered Inca by adoption.
For administrative purposes the empire was divided into regions known as the “four suyus (quarters) of the world,” with Cuzco at its center. The Incas called their empire “Land of the Four Quarters.” One suyu, the Antisuyu, stretched to the east of Cuzco and contained deep, forest-covered valleys that gradually descended into the jungles of the Amazon basin. Indian groups in this region, many of whom were only partially pacified, continued to launch attacks against the Incas. Cuntisuyu included all the land west of Cuzco, including the coastal regions of Peru from Chan Chan to Arequipa. Collasuyu was the largest of the quarters. Located south of Cuzco, it took in Lake Titicaca and regions of Bolivia, Chile, and Argentina. Chincasuyu contained the remaining land to the north of Cuzco.
A blood relative of the emperor served as governor of each quarter. The Incas further divided each quarter into progressively smaller units, with officials of descending rank overseeing the activities of these units. (43) __________. Another official, ideally a leader of a large village, ruled over a smaller area containing about 1,000 peasants. At the level below, ten foremen each supervised a total of 100 peasants. At the lowest organizational level, an official oversaw a group of ten peasants. For every 10,000 people, there were 1,331 officials.
Inca state affairs were complex and tightly controlled. Whole native populations were at times uprooted and resettled in other communities. Often groups were relocated to areas where they were needed for agricultural or mining activities. Sometimes relocations were politically motivated. (44) __________. Furthermore, these relocations facilitated the spread of Inca ideas and culture and promoted unity in the empire.
In order to deal efficiently with such matters, government officers kept strict accounts of all the people, gold, land, crops and projects of the empire. Since the Incas had no system of writing, they kept records by means of a quipu—a series of short, knotted strings hung at intervals from a long top string. By varying the colors and kinds of string used and the spacing of the strings and knots, the Incas could record populations, troops, and tribute, as well as information about their legends and achievements. The quipu was a complex memory aid rather than a literal record, and only a trained quipucamayo, or memory expert, could create or interpret it. An oral comment accompanied each quipu and allowed the quipucamayo to make sense of its meaning. (45) __________. Modern scholars still have not deciphered the codes used in the creation of quipus.
[A] Serving under each governor were ten district governors, each of whom ruled over a district containing about 10,000 peasants.
[B] Following the Spanish conquest and the introduction of records written in Spanish, the Incas lost the ability to read quipus.
[C] Noticeable economic thriving was frequently found, in the records of the local governments, after relocations.
[D] The emperor had one official wife, but he had many royal concubines and his children by these wives often numbered in the hundreds.
[E] Placing Quechua-speaking populations in newly conquered areas impaired the ability of local groups to unite against the Incas.
[F] Relations between relatives of the emperor, governors and officials often posed headaches for the supreme ruler himself, who was interwoven tightly and deeply among them.
[G] These pure-blooded Incas held the most important government, religious, and military posts.
Passage 3
Long before Man lived on the Earth, there were fishes, reptiles, birds, insects, and some mammals. Although some of these animals were ancestors of kinds living today, others are now extinct, that is, they have no descendants alive now. 41) __________.
Very occasionally the rocks show impression of skin, so that, apart from color, we can build up a reasonably accurate picture of an animal that died millions of years ago. The kind of rock in which the remains are found tells us much about the nature of the original land, often of the plants that grew on it, and even of its climate.
42) __________. Nearly all of the fossils that we know were preserved in rocks formed by water action, and most of these are of animals that lived in or near water. Thus it follows that there must be many kinds of mammals, birds, and insects of which we know nothing.
43) __________. There were also crab-like creatures, whose bodies were covered with a horny substance. The body segments each had two pairs of legs, one pair for walking on the sandy bottom, the other for swimming. The head was a kind of shield with a pair of compound eyes, often with thousands of lenses. They were usually an inch or two long but some were 2 feet.
44) __________. Of these, the ammonites are very interesting and important. They have a shell composed of many chambers, each representing a temporary home of the animal. As the young grew larger it grew a new chamber and sealed off the previous one. Thousands of these can be seen in the rocks on the Dorset Coast.
45) __________.
About 75 million years ago the Age of Reptiles was over and most of the groups died out. The mammals quickly developed, and we can trace the evolution of many familiar animals such as the elephant and horse. Many of the later mammals, though now extinct, were known to primitive man and were featured by him in cave paintings and on bone carvings.
[A] The shellfish have a long history in the rock and many different kinds are known.
[B] Nevertheless, we know a great deal about many of them because their bones and shells have been preserved in the rocks as fossils. From them we can tell their size and shape, how they walked, the kind of food they ate.
[C] The first animals with true backbones were the fishes, first known in the rocks of 375 million years ago. About 300 million years ago the amphibians, the animals able to live both on land and in water, appeared. They were giant, sometimes 8 feet long, and many of them lived in the swampy pools in which our coal seam, or layer, was formed. The amphibians gave rise to the reptiles and for nearly 150 million years these were the principal forms of life on land, in the sea, and in the air.
[D] The best index fossils tend to be marine creatures. These animals evolved rapidly and spread over large areas of the world.
[E] The earliest animals whose remains have been found were all very simple kinds and lived in the sea. Later forms are more complex, and among these are the sea-lilies, relations of the starfishes, which had long arms and were attached by a long stalk to the sea bed, or to rocks.
[F] When an animal dies, the body, its bones, or shell, may often be carried away by streams into lakes or the sea and there get covered up by mud. If the animal lived in the sea its body would probably sink and be covered with mud. More and more mud would fall upon it until the bones or shell become embedded and preserved.
[G] Many factors can influence how fossils are preserved in rocks. Remains of an organism may be replaced by minerals, dissolved by an acidic solution to leave only their impression, or simply reduced to a more stable form.
附錄：科學(xué)分支
BRANCHES OF SCIENCE
Classifying sciences involves arbitrary decisions because the universe is not easily split into separate compartments. This article divides science into five major branches: mathematics, physical sciences, earth sciences, life sciences, and social sciences. A sixth branch, technology, draws on discoveries from all areas of science and puts them to practical use. Each of these branches itself consists of numerous subdivisions. Many of these subdivisions, such as astrophysics or biotechnology, combine overlapping disciplines, creating yet more areas of research.
A Mathematical Sciences 數(shù)學(xué)
The mathematical sciences investigate the relationships between things that can be measured or quantified in either a real or abstract form. Pure mathematics differs from other sciences because it deals solely with logic, rather than with nature's underlying laws. However, because it can be used to solve so many scientific problems, mathematics is usually considered to be a science itself.
Central to mathematics is arithmetic算術(shù), the use of numbers for calculation. In arithmetic, mathematicians combine specific numbers to produce a result. A separate branch of mathematics, called algebra代數(shù)學(xué), works in a similar way, but uses general expressions that apply to numbers as a whole. For example, if there are three separate items on a restaurant bill, simple arithmetic produces the total amount to be paid. But the total can also be calculated by using an algebraic formula. A powerful and flexible tool, algebra enables mathematicians to solve highly complex problems in every branch of science.
Geometry 幾何學(xué) investigates objects and the spaces around them. In its simplest form, it deals with objects in two or three dimensions, such as lines, circles, cubes, and spheres. Geometry can be extended to cover abstractions, including objects in many dimensions. Although we cannot perceive these extra dimensions ourselves, the logic of geometry still holds.
In geometry, it is easy to work out the exact area of a rectangle or the gradient (slope) of a line, but there are some problems that geometry cannot solve by conventional means. For example, geometry cannot calculate the exact gradient at a point on a curve, or the area that the curve bounds. Scientists find that calculating quantities like this helps them understand physical events, such as the speed of a rocket at any particular moment during its acceleration.
To solve these problems, mathematicians use calculus微積分學(xué), which deals with continuously changing quantities, such as the position of a point on a curve. Its simultaneous development in the 17th century by English mathematician and physicist Isaac Newton and German philosopher and mathematician Gottfried Willhelm Leibniz enabled the solution of many problems that had been insoluble by the methods of arithmetic, algebra, and geometry. Among the advances that calculus helped develop were the determination of Newton’s laws of motion and the theory of electromagnetism.
B Physical Sciences 自然科學(xué)
The physical sciences investigate the nature and behavior of matter and energy on a vast range of size and scale. In physics itself, scientists study the relationships between matter, energy, force, and time in an attempt to explain how these factors shape the physical behavior of the universe. Physics can be divided into many branches. Scientists study the motion of objects, a huge branch of physics known as mechanics機(jī)械學(xué)、力學(xué) that involves two overlapping sets of scientific laws. The laws of classical mechanics經(jīng)典力學(xué) govern the behavior of objects in the macroscopic world, which includes everything from billiard balls to stars, while the laws of quantum mechanics量子力學(xué) govern the behavior of the particles that make up individual atoms.
Nobody really understands quantum physics, says scientist John Gribbin. Even to advanced physicists, the question of why subatomic particles can act as both waves and particles is still a puzzle. But the classic 19th-century “experiment with two holes” is still the best way to illustrate how they behave that way. Gribbin’s simple explanation of the experiment illuminates why quantum mechanics, which provides the basis for modern physics and the scientific understanding of the structure of matter, still challenges common sense.
Other branches of physics focus on energy and its large-scale effects. Thermodynamics熱力學(xué) is the study of heat and the effects of converting heat into other kinds of energy. This branch of physics has a host of highly practical applications because heat is often used to power machines. Physicists also investigate electrical energy and energy that is carried in electromagnetic waves. These include radio waves, light rays, and X rays—forms of energy that are closely related and that all obey the same set of rules.
(DNA脫氧核糖核酸 Strands. Nucleic acids核酸 are complex molecules produced by living cells and are essential to all living organisms. These acids govern the body’s development and specific characteristics by providing hereditary information and triggering the production of proteins within the body.)
Chemistry化學(xué) is the study of the composition of matter and the way different substances interact—subjects that involve physics on an atomic scale. In physical chemistry, chemists study the way physical laws govern chemical change, while in other branches of chemistry the focus is on particular chemicals themselves. For example, inorganic chemistry無(wú)機(jī)化學(xué) investigates substances found in the nonliving world and organic chemistry有機(jī)化學(xué) investigates carbon-based substances. Until the 19th century, these two areas of chemistry were thought to be separate and distinct, but today chemists routinely produce organic chemicals from inorganic raw materials. Organic chemists have learned how to synthesize many substances that are found in nature, together with hundreds of thousands that are not, such as plastics and pesticides. Many organic compounds, such as reserpine, a drug used to treat hypertension, cost less to produce by synthesizing from inorganic raw materials than to isolate from natural sources. Many synthetic medicinal compounds can be modified to make them more effective than their natural counterparts, with less harmful side effects.
The branch of chemistry known as biochemistry生物化學(xué) deals solely with substances found in living things. It investigates the chemical reactions that organisms use to obtain energy and the reactions they use to build themselves up. Increasingly, this field of chemistry has become concerned not simply with chemical reactions themselves but also with how the shape of molecules influences the way they work. The result is the new field of molecular biology分子生物學(xué)—one of the fastest-growing sciences today.
(Hubble Photo of Galaxy M100. In 1924 American astronomer Edwin Hubble showed that fuzzy patches in the sky called “spiral nebulas” were in fact galaxies like our Milky Way. The orbiting telescope named after him, the Hubble Space Telescope, took the picture of a distant galaxy called M100 in 1995.)
(Models of the Universe. According to the widely accepted theory of the big bang, the universe originated between 10 and 20 billion years ago and has been expanding ever since. Three models are commonly considered to model the future of the universe: a closed model, in which the expansion is finite, and the universe will eventually contract back in upon itself; an open model, in which the universe will continue expanding forever; and a flat model, in which the universe will not collapse upon itself, but also will not get larger and larger forever.)
Physical scientists also study matter elsewhere in the universe, including the planets and stars. Astronomy 天文學(xué) is the science of the heavens in general, while astrophysics天體物理學(xué) is a branch of astronomy that investigates the physical and chemical nature of stars and other objects. Astronomy deals largely with the universe as it appears today, but a related science called cosmology宇宙生成學(xué) looks back in time to answer the greatest scientific questions of all: how the universe began and how it came to be as it is today. (Stephen Hawking; Big Bang)
C Earth Sciences地球?qū)W
(Fossilized Footprints: Although the fossilized remains of dinosaurs are fairly common, their footprints, called trace fossils, are only occasionally found. Such fossils began as footprints in soft mud or clay that eventually hardened in the hot sun. Following hardening these impressions were covered over with fresh mud, sand, or clay during floods and eventually fossilized. Careful examination of such fossilized tracks can reveal useful information about the biology and general movements of dinosaurs.)
(Ocean Life and Resources: A rich variety of resources, both organic and inorganic, exists below the surface of the sea. Estimates indicate that the ocean is capable of producing as much as 200 million metric tons of harvestable organic matter and may contain more than 10 billion tons of gold. The only difficulty in tapping these resources is the complex interrelationship between the chemistry, geology, and physics of the sea. It is nearly impossible to alter one without impacting the others.)
The earth sciences examine the structure and composition of our planet, and the physical processes that have helped to shape it. Geology地質(zhì)學(xué) focuses on the structure of Earth, while geography地理學(xué) is the study of everything on the planet's surface, including the physical changes that humans have brought about from, for example, farming, mining, or deforestation. Scientists in the field of geomorphology地形學(xué) study Earth's present landforms, while mineralogists礦物學(xué)者 investigate the minerals in Earth's crust and the way they formed.
Water dominates Earth's surface, making it an important subject for scientific research. Oceanographers海洋學(xué)者 carry out research in the oceans, while scientists working in the field of hydrology水文學(xué) investigate water resources on land, a subject of vital interest in areas prone to drought. Glaciologists冰河學(xué)家 study Earth's icecaps and mountain glaciers, and the effects that ice has when it forms, melts, or moves. In atmospheric science, meteorology氣象學(xué) deals with day-to-day changes in weather, but climatology氣候?qū)W investigates changes in weather patterns over the longer term.
(Launching Ozone Balloon: Antarctica Earth scientists launch a balloon from the roof of a building at McMurdo research base in Antarctica. The balloon will be used to study Earth’s ozone layer.)
When living things die their remains are sometimes preserved, creating a rich store of scientific information. Paleontology古生物學(xué) is the study of plant and animal remains that have been preserved in sedimentary rock, often millions of years ago. Paleontologists study things long dead and their findings shed light on the history of evolution and on the origin and development of humans. A related science, called palynology孢粉學(xué), is the study of fossilized spores and pollen grains. Scientists study these tiny structures to learn the types of plants that grew in certain areas during Earth’s history, which also helps identify what Earth’s climates were like in the past.
D Life Sciences生命科學(xué)
(Cells細(xì)胞: The word cell refers to several types of organisms. Cells such as paramecia, dinoflagellates, diatoms, and spirochetes are self-maintaining organisms; cells such as lymphocytes, erythrocytes, muscle cells, nerve cells, cardiac muscle, and chloroplasts are more specialized cells that are a part of higher multicellular organisms. Regardless of size or whether the cell is a complete organism or just part of an organism, all cells have certain structural components in common. All cells have some type of outer cell boundary that permits some materials to leave and enter the cell and a cell interior composed of a water-rich, fluid material called cytoplasm that contains hereditary material in the form of deoxyribonucleic acid (DNA).
Erythrocytes紅血球: Erythrocytes, or red blood cells, are the primary carriers of oxygen to the cells and tissues of the body. The biconcave shape of the erythrocyte is an adaptation for maximizing the surface area across which oxygen is exchanged for carbon dioxide. Its shape and flexible plasma membrane allow the erythrocyte to penetrate the smallest of capillaries.
Smooth Muscle平滑肌: Human smooth muscle, also referred to as visceral or involuntary muscle, is composed of slender, spindle-shaped cells. Controlled by the autonomic nervous system, smooth muscle cells help form the structure of the skin, blood vessels, and internal organs.
Cardiac Muscle心肌: Cardiac muscle is a unique muscle tissue found only in the heart. Requiring a constant supply of oxygen, cardiac muscle will quickly die if obstructions occur in the arteries leading to the heart. Heart attacks occur from the damage caused by insufficient blood supply to cardiac muscle.
Nerve Cells神經(jīng)元,神經(jīng)細(xì)胞: The central cell body is clearly visible in each of the cells, as are the dendrites. The dendrites are short extensions of the nerve cell body that function in the reception of stimuli.
Spirochete Bacteria螺旋菌, which are included within the kingdom Prokaryotae, are single-celled organisms lacking a well-defined internal cellular organization.
Chloroplasts葉綠體: An examination of leaves, stems, and other types of plant tissue reveals the presence of tiny green, spherical structures called chloroplasts, visible here in the cells of an onion. Chloroplasts are essential to the process of photosynthesis, in which captured sunlight is combined with water and carbon dioxide in the presence of the chlorophyll molecule to produce oxygen and sugars that can be used by animals. Without the process of photosynthesis, the atmosphere would not contain enough oxygen to support animal life.)
The life sciences include all those areas of study that deal with living things. Biology生物學(xué) is the general study of the origin, development, structure, function, evolution, and distribution of living things. Biology may be divided into botany植物學(xué), the study of plants; zoology動(dòng)物學(xué), the study of animals; and microbiology微生物學(xué), the study of the microscopic organisms, such as bacteria, viruses, and fungi. Many single-celled organisms play important roles in life processes and thus are important to more complex forms of life, including plants and animals.
Genetics遺傳學(xué) is the branch of biology that studies the way in which characteristics are transmitted from an organism to its offspring. In the latter half of the 20th century, new advances made it easier to study and manipulate genes at the molecular level, enabling scientists to catalog all the genes found in each cell of the human body. Exobiology外空生物學(xué), a new and still speculative field, is the study of possible extraterrestrial life. Although Earth remains the only place known to support life, many believe that it is only a matter of time before scientists discover life elsewhere in the universe.
While exobiology is one of the newest life sciences, anatomy解剖學(xué) is one of the oldest. It is the study of plant and animal structures, carried out by dissection or by using powerful imaging techniques. Gross anatomy大體解剖學(xué) deals with structures that are large enough to see, while microscopic anatomy顯微解剖學(xué) deals with much smaller structures, down to the level of individual cells.
Correcting Genetic Diseases: Gene therapy基因療法 may someday be able to cure hereditary diseases, such as hemophilia and cystic fibrosis, which are caused by missing or defective genes. In one type of gene therapy, genetically engineered viruses are used to insert new, functioning genes into the cells of people who are unable to produce certain hormones or proteins necessary for the body to function normally.
Ecosystem生態(tài)系統(tǒng): The illustration presents a simplified ecosystem, or a community of interacting living and nonliving things. Producers, consumers, decomposers, and abiotic matter form an integrated, functioning whole driven by the Sun’s energy.
Physiology生理學(xué) explores how living things work. Physiologists study processes such as cellular respiration and muscle contraction, as well as the systems that keep these processes under control. Their work helps to answer questions about one of the key characteristics of life—the fact that most living things maintain a steady internal state when the environment around them constantly changes.
Together, anatomy and physiology form two of the most important disciplines in medicine醫(yī)學(xué), the science of treating injury and human disease. General medical practitioners have to be familiar with human biology as a whole, but medical science also includes a host of clinical specialties. They include sciences such as cardiology心(臟)病學(xué), urology泌尿?qū)W, and oncology腫瘤學(xué), which investigate particular organs and disorders, and also pathology病理學(xué), the general study of disease and the changes that it causes in the human body.
(Greenhouse Research: The controlled environment of a greenhouse provides an ideal setting for plant research.)
As well as working with individual organisms, life scientists also investigate the way living things interact. The study of these interactions, known as ecology生態(tài)學(xué), has become a key area of study in the life sciences as scientists become increasingly concerned about the disrupting effects of human activities on the environment.
E Social Sciences社會(huì)科學(xué)
(Footprints: From the Past In 1978 in Laetoli, Tanzania, a research team led by British paleoanthropologist Mary Leakey discovered these 3.6-million-year-old human footprints preserved in a layer of hardened volcanic ash. Two early humans of the species Australopithecus afarensis left the footprints as they walked across the African savanna. )
The social sciences explore human society past and present, and the way human beings behave. They include sociology社會(huì)學(xué), which investigates the way society is structured and how it functions, as well as psychology心理學(xué), which is the study of individual behavior and the mind. Social psychology社會(huì)心理學(xué) draws on research in both these fields. It examines the way society influences people's behavior and attitudes.
(Origins of Anthropology The modern study of anthropology had its origins in the European exploration and colonization of lands in the Americas, Asia, Africa, and the Pacific. European contacts with vastly different peoples sparked an interest in understanding and explaining human diversity, the goals of anthropology. )
Another social science, anthropology人類學(xué), looks at humans as a species and examines all the characteristics that make us what we are. These include not only how people relate to each other but also how they interact with the world around them, both now and in the past. As part of this work, anthropologists often carry out long-term studies of particular groups of people in different parts of the world. This kind of research helps to identify characteristics that all human beings share and those that are the products of local culture, learned and handed on from generation to generation.
The social sciences also include political science政治學(xué), law法學(xué), and economics經(jīng)濟(jì)學(xué), which are products of human society. Although far removed from the world of the physical sciences, all these fields can be studied in a scientific way. Political science and law are uniquely human concepts, but economics has some surprisingly close parallels with ecology. This is because the laws that govern resource use, productivity, and efficiency do not operate only in the human world, with its stock markets and global corporations, but in the nonhuman world as well.
F Technology技術(shù)
（Suspension Bridge吊橋: Civil engineers construct suspension bridges in areas where building a bridge with mid-span supports would be either extremely difficult or overly expensive. The span hangs from two enormous main cables, eliminating the need to bolster the bridge from underneath. The Clifton Suspension Bridge, completed in 1864, spans the Avon Gorge in Bristol, England.）
（Wind Tunnel風(fēng)洞: A wind tunnel is used to test the aerodynamic efficiency of an automobile. Streamlined body designs can greatly reduce the drag forces on moving objects such as automobiles or airplanes.）
In technology, scientific knowledge is put to practical ends. This knowledge comes chiefly from mathematics and the physical sciences, and it is used in designing machinery, materials, and industrial processes. In general, this work is known as engineering工程學(xué), a word dating back to the early days of the Industrial Revolution, when an "engine" was any kind of machine.
（Computer-Aided Design計(jì)算機(jī)輔助設(shè)計(jì) of Jet Engine: The plans for this jet turbine engine were created with computer-aided design (CAD) software. Engineers can check the architectural details, slicing through any section of the engine’s computer-generated blueprint or viewing it from any angle.）
Engineering has many branches, calling for a wide variety of different skills. For example, aeronautical engineers need expertise in the science of fluid flow, because airplanes fly through air, which is a fluid. Using wind tunnels and computer models, aeronautical engineers strive to minimize the air resistance generated by an airplane, while at the same time maintaining a sufficient amount of lift. Marine engineers also need detailed knowledge of how fluids behave, particularly when designing submarines that have to withstand extra stresses when they dive deep below the water’s surface. In civil engineering, stress calculations ensure that structures such as dams and office towers will not collapse, particularly if they are in earthquake zones. In computing, engineering takes two forms: hardware design and software design. Hardware design refers to the physical design of computer equipment (hardware). Software design is carried out by programmers who analyze complex operations, reducing them to a series of small steps written in a language recognized by computers.
（Genetic Engineering基因工程: Genetic engineering enables scientists to produce clones無(wú)性繁殖, 克隆 of cells or organisms that contain the same genes. 1. Scientists use restriction enzymes酶 to isolate a segment of deoxyribonucleic acid (DNA) 脫氧核糖核酸 that contains a gene of interest—for example, the gene regulating insulin production. 2. A plasmid extracted from a bacterium and treated with the same restriction enzyme can hybridize with this fragment’s “sticky” ends of complementary DNA. 3. The hybrid plasmid is reincorporated into the bacterium, where it replicates as part of the cell’s DNA. 4. A large number of identical daughter cells (clones) can be cultured and their gene products extracted for human use.）
In recent years, a completely new field of technology has developed from advances in the life sciences. Known as biotechnology生物工藝學(xué), it involves such varied activities as genetic engineering, the manipulation of genetic material of cells or organisms, and cloning, the formation of genetically uniform cells, plants, or animals. Although still in its infancy, many scientists believe that biotechnology will play a major role in many fields, including food production, waste disposal, and medicine.
Artificial Intelligence (AI)人工智能, a term that in its broadest sense would indicate the ability of an artifact to perform the same kinds of functions that characterize human thought. The possibility of developing some such artifact has intrigued human beings since ancient times. With the growth of modern science, the search for AI has taken two major directions: psychological and physiological research into the nature of human thought, and the technological development of increasingly sophisticated computing systems. In the latter sense, the term AI has been applied to computer systems and programs capable of performing tasks more complex than straightforward programming, although still far from the realm of actual thought. The most important fields of research in this area are information processing, pattern recognition, game-playing computers, and applied fields such as medical diagnosis. Current research in information processing deals with programs that enable a computer to understand written or spoken information and to produce summaries, answer specific questions, or redistribute information to users interested in specific areas of this information. Essential to such programs is the ability of the system to generate grammatically correct sentences and to establish linkages between words, ideas, and associations with other ideas. Research has shown that whereas the logic of language structure—its syntax—submits to programming, the problem of meaning, or semantics, lies far deeper, in the direction of true AI. Many scientists remain doubtful that true AI can ever be developed. The operation of the human mind is still little understood, and computer design may remain essentially incapable of analogously duplicating those unknown, complex processes. Various routes are being used in the effort to reach the goal of true AI. One approach is to apply the concept of parallel processing—interlinked and concurrent computer operations. Another is to create networks of experimental computer chips, called silicon neurons, that mimic data-processing functions of brain cells. Using analog technology, the transistors in these chips emulate nerve-cell membranes in order to operate at the speed of neurons.
Network（網(wǎng)絡(luò)）: techniques, physical connections, and computer programs used to link two or more computers. Network users are able to share files, printers, and other resources; send electronic messages; and run programs on other computers. A network has three layers of components: application software, network software, and network hardware. A network has two types of connections: physical connections that let computers directly transmit and receive signals and logical, or virtual, connections that allow computer applications, such as word processors, to exchange information. The wide use of notebook and other portable computers drives advances in wireless networks（無(wú)線網(wǎng)絡(luò)）. Wireless networks use either infrared or radio frequency transmissions to link these mobile computers to networks. Infrared wireless LANs work only within a room, while wireless LANs based on radio-frequency transmissions can penetrate most walls. If it can be integrated into a network, this new technology will make it easy, inexpensive, and incredibly fast to send information, such as video and memory-sensitive three-dimensional images.