Modern manufacturers, who need reliable sources of materials and technologically advanced components to operate profitably, face an increasingly difficult choice between owning the producers of these items (a practice known as backward integration) and buying from independent producers. Manufacturers who integrate may reap short-term rewards, but they often restrict their future capacity for innovative product development. Backward integration removes the need for some purchasing and marketing functions, centralizers overhead, and permits manufacturers to eliminate duplicated efforts in research and development. Where components are commodities (ferrous metals or petroleum, for example), backward integration almost certainly boosts profits. Nevertheless, because product innovation means adopting the most technologically advanced and cost-effective ways of making components, backward integration may entail a serious risk for a technologically active company-for example, a producer of sophisticated consumer electronics. A company that decides to make rather than buy important parts can lock itself into an outdated technology. Independent suppliers may be unwilling to share innovations with assemblers with whom they are competing. Moreover, when an assembler sets out to master the technology of producing advanced components, the resulting demands on its resources may compromise its ability to assemble these components successfully into end products. Long-term contracts with suppliers can achieve many of the same cost benefits as backward integration without compromising a company’s ability to innovate. However, moving away from backward integration is not a complete solution either. Developing innovative technologies requires independent suppliers of components to invest huge sums in research and development. The resulting low profit margins on the sale of components threaten the long-term financial stability of these firms. Because the ability of end-product assemblers to respond to market opportunities depends heavily on suppliers of components, assemblers are often forced to integrate by purchasing the suppliers of components just to keep their suppliers in business. 257. According to the passage, all of the following are benefits associated with backward integration EXCEPT: (A) improvement in the management of overhead expenses (B) enhancement of profit margins on sales of components (C) simplification of purchasing and marketing operations (D) reliability of a source of necessary components (B) (E) elimination of unnecessary research efforts 想问一下这道题目的D选项为什么不对呢?文中的Where components are commodities (ferrous metals or petroleum, for example), backward integration almost certainly boosts profits. 这句话不是B的意思吗?谢谢大家。 Homeostasis, an animal’s maintenance of certain internal variables within an acceptable range, particularly in extreme physical environments, has long interested biologists. The desert rat and the camel in the most water-deprived environments, and marine vertebrates in an all-water environment, encounter the same regulatory problem: maintaining adequate internal fluid balance. For desert rats and camels, the problem is conservation of water in an environment where standing water is nonexistent, temperature is high, and humidity is low. Despite these handicaps, desert rats are able to maintain the osmotic pressure of their blood, as well as their total boy-water content, at approximately the same levels as other rats. One countermeasure is behavioral: these rats stay in burrows during the hot part of the day, thus avoiding loss of fluid through panting or sweating, which are regulatory mechanisms for maintaining internal body temperature by evaporative cooling. Also, desert rats’ kidneys can excrete a urine having twice as high a salt content as sea water. Camels, on the other hand, rely more on simple endurance. They cannot store water, and their reliance on an entirely unexceptional kidney results in a rate of water loss through renal function significantly higher than that of desert rats. As a result, camels must tolerate losses in body water of up to thirty percent of their body weight. Nevertheless, camels do rely on a special mechanism to keep water loss within a tolerable range: by sweating and panting only when their body temperature exceeds that which would kill a human, they conserve internal water. Marine vertebrates experience difficulty with their water balance because though there is no shortage of seawater to drink, they must drink a lot of it to maintain their internal fluid balance. But the excess salts from the seawater must be discharged somehow, and the kidneys of most marine vertebrates are unable to excrete a urine in which the salts are more concentrated than in seawater. Most of these animals have special salt-secreting organs outside the kidney that enable them to eliminate excess salt. 261. Which of the following most accurately states the purpose of the passage? (A) To compare two different approaches to the study of homeostasis (B) To summarize the findings of several studies regarding organisms’ maintenance of internal variables in extreme environments (C) To argue for a particular hypothesis regarding various organisms’ conservation of water in desert environments (D) To cite examples of how homeostasis is achieved by various organisms (D) (E) To defend a new theory regarding the maintenance of adequate fluid balance 想问一下这道题目的B和D应该怎么区分啊?谢谢大家。 Where components are commodities (ferrous metals or petroleum, for example), backward integration almost certainly boosts profits. 这句话不是B的意思吗?谢谢大家。 Homeostasis, an animal’s maintenance of certain internal variables within an acceptable range, particularly in extreme physical environments, has long interested biologists. The desert rat and the camel in the most water-deprived environments, and marine vertebrates in an all-water environment, encounter the same regulatory problem: maintaining adequate internal fluid balance. For desert rats and camels, the problem is conservation of water in an environment where standing water is nonexistent, temperature is high, and humidity is low. Despite these handicaps, desert rats are able to maintain the osmotic pressure of their blood, as well as their total boy-water content, at approximately the same levels as other rats. One countermeasure is behavioral: these rats stay in burrows during the hot part of the day, thus avoiding loss of fluid through panting or sweating, which are regulatory mechanisms for maintaining internal body temperature by evaporative cooling. Also, desert rats’ kidneys can excrete a urine having twice as high a salt content as sea water. Camels, on the other hand, rely more on simple endurance. They cannot store water, and their reliance on an entirely unexceptional kidney results in a rate of water loss through renal function significantly higher than that of desert rats. As a result, camels must tolerate losses in body water of up to thirty percent of their body weight. Nevertheless, camels do rely on a special mechanism to keep water loss within a tolerable range: by sweating and panting only when their body temperature exceeds that which would kill a human, they conserve internal water. Marine vertebrates experience difficulty with their water balance because though there is no shortage of seawater to drink, they must drink a lot of it to maintain their internal fluid balance. But the excess salts from the seawater must be discharged somehow, and the kidneys of most marine vertebrates are unable to excrete a urine in which the salts are more concentrated than in seawater. Most of these animals have special salt-secreting organs outside the kidney that enable them to eliminate excess salt. 261. Which of the following most accurately states the purpose of the passage? (A) To compare two different approaches to the study of homeostasis (B) To summarize the findings of several studies regarding organisms’ maintenance of internal variables in extreme environments (C) To argue for a particular hypothesis regarding various organisms’ conservation of water in desert environments (D) To cite examples of how homeostasis is achieved by various organisms (D) (E) To defend a new theory regarding the maintenance of adequate fluid balance 想问一下这道题目的B和D应该怎么区分啊?谢谢大家。 |