教材习题
Exercises
I. Oral Presentation
Make a five-minute presentation in class based on your research.
Suggested topics: 1. Barry Commoner 2. Comment on the writing style of the text
» 3. Explain what you know about bacteria
II. Questions
A. Questions on the Content
1. What is the main idea of the first paragraph?
2. How does the writer define the term ecology in Paragraph 3?
3. What is the first law of ecology? Can you sum up the main points of the law in your own words?
4. What are Paragraphs 9 and 10 about? What is the rabbit-lynx system? Under what circumstances does the system collapse?
5. How does eutrophication cause the entire aquatic cycle to collapse?
6. Why is the dumping of sewage into the water a threat to the stability of the whole aquatic system?
7. Can ecosystems collapse easily? Why or why not?
8. What is the second law of ecology? What are the main points of this law?
B. Questions on Structure and Style
1. What is the topic sentence of Paragraph 2? How is the thesis statement developed?
2. How does the writer explain the meaning of cybernetics in a way that is clear and easy to understand?
3. What example does the writer employ to illustrate the concept of an ecological circle in Paragraph 7?
4. What does the writer compare ecosystems to in Paragraph 16? What point is he trying to explain here?
5. What methods does the writer use to make this scientific writing about complicated concepts relatively easy to understand? Do you find these methods helpful for your reading?
6. What are some of the characteristics of science writing as shown in this piece?
III. Paraphrase
Explain the following sentences in your own words, bringing out any implied meanings.
1
All this, many times multiplied and organized species by species in intricate, precise relationships, makes up the vast network of life on the earth. (Para. 2) It is the science of planetary housekeeping. (Para. 3)
3. Our ability to picture the behavior of such systems has been helped considerably
10.
by the development, even more recent than ecology, of the science of cybernetics. (Para. 5) In quite a similar way, stabilizing cybernetic relations are built into an ecological
cycle. (Para. 7)
. The most famous examples of such ecological oscillations are the periodic
fluctuations of the size of fur-bearing animal populations. (Para. 9)
These oscillations are built into the operation of the simple cycle, in which the lynx population is positively related to the number of rabbits and the rabbit population is negatively related to the number of lynx. (Para. 9)
Ecosystems differ considerably in their rate characteristics and therefore vary a great deal in the speed with which they react to changed situations or approach the point of collapse. (Para. 15)
. Environmental pollution is often a sign that ecological links have been cut and that
the ecosystem has been artificially simplified and made more vulnerable to stress and to final collapse. (Para. 16)
A persistent effort to answer the question, “Where does it go?” can yield a surprising amount of valuable information about an ecosystem. (Para. 20) Consider, for example, the fate of a household item which contains mercury—a
substance with environmental effects that have just recently surfaced. (Para. 20)
IV. Practice with Words and Expressions
A. Look up the dictionary and explain the meaning of the italicized words and phrases.
We 2.
Ot oy. Yt
Fungi degrade the bodies of dead plants and animals. (Para. 2)
...simplifying generalizations exemplified by, say, the Jaws of physics. (Para. 3) ...among different living organisms, and between populations, species, and individual organisms... (Para. 4)
Our ability to picture the behavior of such systems has been helped... (Para. 5)
...to the inventive mind of the late Norbert Wiener. (Para. 5)
If the ship veers off the chosen compass course... (Para. 6)
...the periodic fluctuations of the size of fur-bearing animal populations. (Para. 9)
The metabolic rates of these organisms...are inversely related to their size. (Para. 13)
9. 10. Ot:
...the overall rate of turnover must be governed by the slowest step... (Para. 14) ... with branches to form a network or a fabric of interconnections. (Para. 16)
...a substance with environmental effects that have just recently surfaced. (Para. 20)
B. Replace the italicized formal, or technical words and terms with everyday words
and expressions.
i
If the helmsman turns the rudder too far in response to a small deflection of the compass needle... (Para. 6) ( )
This depletes the supply of inorganic nutrients... (Para. 7) ( )
...the periodic fluctuations of the size of fur-bearing animal populations... (Para. 9) Ae,
...the rising population of lynx increasingly ravages the rabbit population... (Para. 9) od
5, ...when an oscillation swings so wide of the balance point... (Para. 10) ( )
6. When such an effect originates outside the cycle... (Para. 14) ( )
7. ...amplification and intensification processes of considerable magnitude. (Para. 17)
9. 10. vale 12. 13: 14.
fh ie
...a small perturbation in one place may have large, distant, long-delayed effects. (Para. 18) ( )
...what is excreted by one organism as waste... (Para. 19) ( )
...-mercury vapor is toxic. (Para. 20) ( )
...which convert it to methyl mercury. (Para. 20) ( )
This is soluble and taken up by fish... (Para. 20) ( )
...the mercury becomes deposited in his organs... (Para. 20) ( )
It is also an excellent way to counteract the prevalent notion... (Para. 21) ( )
C. Give the Chinese equivalents of the following terms.
15. 17;
ep neae ait RL oo
bacteria (Para. 2) 2. ecosphere (Para. 3) cybernetics (Para. 5) 4. compass (Para. 6)
rudder (Para. 6) 6. inorganic products (Para. 7) algae (Para. 7) 8. lynx (Para. 9) photosynthesis (Para. 11) 10. oxygen content (Para. 11) metabolism (Para. 14) . 12. food chain (Para. 17) oxidize (Para. 17) 14. nitrate (Para. 19) phosphate (Para. 19) 16. dry-cell battery (Para. 20) mercury (Para. 20) 18. methyl (Para. 20)
V. Translation _ ii as
A. Translate the following sentences into Chinese.
1. These links are bewildering in their variety and marvelous in their intricate detail. (Para. 2)
2. For the environment is, so to speak, the house created on the earth by living things for living things. (Para. 3)
3. We owe the basic concept, and the word itself, to the inventive mind of the late Norbert Wiener. (Para. 5)
4. In such an oscillating system, there is always the danger that the whole system will collapse when an oscillation swings so wide of the balance point that the system can no longer compensate for it. (Para. 10)
5. In the ship system, the compass needle swings in fractions of a second; the helmsman’s reaction takes some seconds; the ship responds over a time of minutes. (Para. 12)
6. In the aquatic ecosystem, each biological step also has a characteristic reaction time, which depends on the metabolic and reproductive rates of the organisms involved. (Para. 13)
7. If the metabolic rate of a fish is 1, the algal rate is about 100, and the bacterial rate about 10,000. (Para. 13)
8. The more complex the ecosystem, the more successfully it can resist a stress. (Para. 16)
9. Most ecosystems are so complex that the cycles are not simple circular paths, but are crisscrossed with branches to form a network or a fabric of interconnections. (Para 16)
10. Applied to ecology, the law emphasizes that in nature there is no such thing as “waste.” (Para. 19)
11. One of the chief reasons for the present environmental crisis is that great amounts of materials have been extracted from the earth, converted into new forms, and discharged into the environment without taking into account that “everything has to go somewhere.” (Para. 21)
B. Translate Paragraphs 14 and 20 into Chinese.
Read, Think and Comment
ey
Below is a passage from another Commoner book, Making Peace with the Planet. Read it and prepare to respond to the following questions: What is the main idea of each paragraph? Where is the thesis of the passage stated? What striking metaphor does the writer use to sum up his main argument?
People live in two worlds. Like all living things, we inhabit the natural world, created over the Earth’s 5-billion-year history by physical, chemical, and biological processes. The other world is our own creation: homes, cars, farms, factories, laboratories, food, clothing, books, paintings, music, poetry. We accept responsibility for events of our own world, but not for what occurs in the natural one. Its storms, droughts, and floods are “acts of God,” free of human control and exempt from our responsibility.
Now, on a planetary scale, this division has been breached. With the appearance of a continent-sized hole in the Earth's protective ozone layer and the threat of global warming, even droughts, floods, and heat waves may become unwitting acts of man.
We have become accustomed to the now mundane image of the Earth ©
as seen from the first expedition to the moon—a beautiful blue sphere decorated by swirls of fleecy clouds. It is a spectacular natural object; at that distance, no overt signs of human activity are visible. But this image is misleading. Even if the global warming catastrophe never materializes, and the ozone hole remains an esoteric, polar phenomenon, already human activity has profoundly altered global conditions in ways that may not register on the camera. Everywhere in the world, there is now radioactivity that was not there before, the dangerous residue of nuclear explosions and the nuclear power industry; noxious flames of smog blanket over major cities;
} ee ales
学习指南参考答案
A.
1. The first paragraph serves as a general introduction to the environment in which each species is closely related to others and has particular influences on them.
2. The writer first provides a definition of ecology with scientific terms: The science that studies these relationships and the processes linking each living thing to the physical and chemical environment. Then he adopts a metaphor to define it: It is the science of planetary housekeeping.
3. The first law of ecology is “everything is connected to everything else.” The ecosystem is influenced and stabilized by the interconnection of different species, which is like a net. The balance is carefully kept by the helmsman. However, once the balance is broken, the whole system will collapse.
4. These two paragraphs mainly focus on ecological oscillation. The rabbit-lynx system is about the coexistence of rabbit and lynx, which is used to explain the periodic fluctuations of ecological oscillations. When the rabbit population drops and no longer reproduces, the lynx will starve and the system collapses.
5. First, the nutrient level of the water becomes so high that algae grow to a thickness that reduces its photosynthetic efficiency. Then the algae die and release organic debris. The decay will totally destroy the oxygen content of the water and thus the entire water cycle collapses.
6. As an external factor, the sewage will intrude into the original balance of the water cycle. As a result, the algae need to consume more oxygen to digest the sewage. When the speed of oxygen consumption surpasses that of production, the whole system collapses.
7. Not necessarily. It depends on the complexity of ecosystem because it can determine its ability to resist stress: the more complex the ecosystem, the more successfully it can resist stress, and vice versa.
8. The second law of ecology is “everything must go somewhere.” Each component of ecosystem is indestructible and there is no such thing as “waste.” Through life process everything is cycled in different forms.
B.
1. The topic sentence of Para. 2 is: Each living species is also linked to many others. The writer first describes it as “bewildering in their variety and marvelous in their intricate detail,” and then uses the example of deer and bacteria. Finally, the writer develops the thesis statement into an enlarged discussion scope.
2. The writer starts his explanation of the word with the Greek origin of the word “cybernetics” to attract readers’ attention. Then he uses a correspondent metaphor of ship to explain this term to make the explanation vivid and clear.
3. The fresh water ecological cycle: fish—organic waste—bacteria of decay—inorganic products—algae fish.
4. The writer compares ecosystems to a net. He is trying to explain the interconnections of ecosystem and its ability to resist stress.
5. The writer uses metaphors and examples to make complicated concepts easier to understand. These methods can assist common readers who do not have scientific background in comprehension.
6. The writer uses definition, analogy and comparison to explain terms. The word choice is plain and simple while the sentence structures are concise and straightforward.
1. The above is just a single example showing the connections of deer to other forms of life. But in reality, this is added many times and organized species by species in precise relationships with many other details. And this makes up the large and extensive network of life on the earth.
2. Ecology is the science that deals with how the affairs of our house, the planet, are managed.
3. The development of the science of cybernetics has greatly improved our ability to describe the behavior of ecosystems, which is even younger than the science of ecology.
4. Similar to the ship system, cybernetics systems with stabilizing effects are an integral part of an ecological cycle.
5. The fact that the size of fur-bearing animal populations changes periodically can clearly illustrate such ecological oscillations.
6. Since more rabbits provide more food for lynx, therefore the rising population of rabbits increases the population of the lynx. Reversely, when the number of lynx increases, rabbits are more fiercely hunted and consumed, as a result of which, the population of the rabbits decreases.
7. There are many different ecosystems on the earth: the air, the fresh water, the ocean, the soil, the desert, the forest, etc. Their rate characteristics differ and that’s why they respond to changed situations or come near to the point of collapse with differing speeds.
8. Environmental pollution indicates that some ecological links have been destroyed. As a result, the ability of the ecosystem to resist stress is simplified due to human activities, therefore it is more vulnerable to final collapse.
9. If everything must go somewhere, we may persistently try to answer the question, “Where does it go?” Because in doing so, we can learn a great deal of valuable information about the ecosystem.
10. Let’s examine what’s going to happen to a household item which contains mercury which is a substance that can cause environmental effects that science has recently discovered.
A.
1. degrade: to change a substance, chemical, etc. to a simpler form
2. law: a statement that describes and explains how something in nature works
3. population: all the organisms living in a given area
4. picture: to describe something clearly
5. late: deceased, used of persons
6. veer off: to change direction; to turn or swing around
7. fluctuation: sudden changes in something such as the price, amount, or level of something
8. inversely, in exactly opposite ways turnover: the continuous process of loss and replacement of a constituent (as a cell or tissue) of a living system
9. turnover: the rate at which things leave or be replaced
10. fabric, texture, quality; underlying structure, framework
11. surface: (information or feelings) to become known after being hid .
B.
1. turning aside
2. reduces
3. sudden changes
4. destroys
5. a regular movement between two limits
6. starts to develop
7. greatness
8. disturbance
9. released
10. poisonous
11. turns
12. can be dissolved into liquid forms
13. stored and kept
14. commonly held
C.
1. 细菌
2. 生态圈
3. 控制论
4. 罗盘，罗盘仪
5. 舵
6. 无机物
7. 水藻，海藻
8. 猞猁
9. 硝酸盐，硝酸酯
10. 磷酸盐，磷酸酯
11. 光合作用
12. 氧含量
13. 代谢作用
14. 食物链
15. 氧化
16. 干电池
17. 汞
18. 甲基
V. See the translation of the text.
1. Para. 1 focuses on the traditional concepts of the two worlds’ people live in the natural world and the world of our creation. Para. 2 centers on the notion that division between these two worlds has now been breached due to unwitting acts of man. Para. 3 mainly talks about the idea that human activity has profoundly changed the globe that everywhere has radioactivity that was not there before. Para. 4 states that we should understand the interaction between our two worlds and these two worlds are at war.
2. It is stated in Para. 4: Clearly, we need to understand the interaction between our two worlds: the natural ecosphere, the thin global skin of air, water, and soil and the plants and animals that live in it, and the man-made technosphere—powerful enough to deserve so grandiose a term.
3. The writer used personification to describe the counterattack of the natural world, for example, “threaten” “dry up” “contaminate” and “poison”. These words stress on the ferocity of the “war” we are at with the nature.