文勇的新托福黄金&ccedil

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Unformatted text preview: f acorns is small compared with the energy spent on building leaves, trunk, and roots. Once an oak tree becomes established, it is likely to survive minor cycles of drought and even fire. A population of oaks is likely to be relatively stable through time, and its survival is likely to depend more on its ability to withstand the pressures of competition 133 Mail@liuwenyong.com 在在在在在在 www.liuwenyong.com 在在在在在在在在在在在在在在在,在在在在在在在在在在 or predation than on its ability to take advantage of chance events. It should be noted, however, that the pure opportunist or pure competitor is rare in nature, as most species fall between the extremes of a continuum, exhibiting a blend of some opportunistic and some competitive characteristics. Paragraph 1: Growth, reproduction, and daily metabolism all require an organism to expend energy. The expenditure of energy is essentially a process of budgeting, just as finances are budgeted. If all of one’s money is spent on clothes, there may be none left to buy food or go to the movies. Similarly, a plant or animal cannot squander all its energy on growing a big body if none would be left over for reproduction, for this is the surest way to extinction. 1. The word squander in the passage is closest in meaning to ○ Extend ○Transform ○ Activate ○ Waste 2. The word none in the passage refers to ○ Food ○ Plant or animal ○ Energy ○ Big body 3. In paragraph 1, the author explains the concept of energy expenditure by ○ Identifying types of organisms that became extinct ○ Comparing the scientific concept to a familiar human experience ○ Arguing that most organisms conserve rather than expend energy ○ Describing the processes of growth, reproduction, and metabolism Paragraph 3 在 Almost all of an organism’s energy can be diverted to reproduction, with very little allocated to building the body. Organisms at this extreme are “opportunists.” At the other extreme are “competitors,” almost all of whose resources are invested in building a huge body, with a bare minimum allocated to reproduction. 4. According to the passage, the classification of organisms as “opportunists” or “competitors” is determined by ○ How the genetic information of an organism is stored and maintained ○ The way in which the organism invests its energy resources ○ Whether the climate in which the organism lives is mild or extreme ○ The variety of natural resources the organism consumes in its environment Paragraph 4在Dandelions are good examples of opportunists. Their seed heads raised just high enough above the ground to catch the wind, the plants are no bigger than they need be, their stems are hollow, and all the rigidity comes from their water content. Thus, a minimum investment has been made in the body that becomes a platform for seed dispersal. These very short­lived plants reproduce prolifically; that is to say they provide a constant rain of seed in the neighborhood of parent plants. A new plant will spring up wherever a seed falls on a suitable soil surface, but because they do not...
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