competition 托福阅读真题

competition 托福阅读真题， 今天金宝搏188入口 就来为大家分析这个问题。

competition 

competition托福阅读原文及真题

competition 托福阅读真题

competition 托福阅读真题解析及答案

competition 托福阅读真题译文

托福阅读试题

1.The phrase"mechanisms of natural selection"in the passage（paragraph 1）is closest in meaning to

A.types of natural selection.

B.dangers of natural selection.

C.problems natural selection solves.

D.ways natural selection works.

2.According to paragraph 1,what is one effect of competition among individuals of different species?

A.It results in the eventual elimination of the resource for which they are competing.

B.It leads to competition among individuals of the same species.

C.It encourages new species to immigrate to an area.

D.It controls the number of individuals in the competing populations.

3.The word"indigenous"in the passage（paragraph 1）is closest in meaning to

A.native.

B.rate.

C.most.

D.numerous.

4.In paragraph 1,why does the author mention what happened in New Zealand?

A.To indicate that Darwin understood the importance of competition.

B.To illustrate that competition can lead to the extinction of species.

C.To identify where the idea of competition among species first arose.

D.To argue against the idea that the process of selection is a natural occurrence.

5.According to paragraph 2,competition is not usually a significant factor among two coexisting species when

A.one of the species has only recently moved into the territory of the other.

B.the species are closely related to each other.

C.the population of one species is much larger than that of the other.

D.both of the species are herbivores.

6.The word"graphically"in the passage（paragraph 2）is closest in meaning to

A.vividly.

B.frequently.

C.broadly.

D.typically.

7.In paragraph 2,why does the author talk about what happened as a result of North and South America becoming joined at the Isthmus of Panama?

A.To make the point that predation can have as much effect on species survival as competition does.

B.To show how the ability to switch to an alternative resource can give a species a competitive advantage.

C.To account for the current species composition of North and South America.

D.To provide an example of the serious effects of competition between unrelated species.

8.Paragraph 3 supports the idea that Gause's experiments were important because they

A.provided a situation in which competition could be removed from the interaction between two species.

B.showed that previous ideas about the extent to which competition determines the composition of a community were completely mistaken.

C.helped establish that competition will remove all but one species from any given ecological niche.

D.offered evidence that competition between species is minimal when there is an overabundance of a single food source.

9.Which of the sentences below best expresses the essential information inthe highlighted sentence in the passage（paragraph 3）?Incorrect choices change the meaningin important ways or leave out essential information.

A.Apparent exceptions to this law usually involves cases in which two species compete for the same major resource but occupy slightly different niches.

B.Although it may appear that two species always have different niches,many exceptions show that species compete with each other.

C.Cases in which two species not only compete for a shared resource but also occupy similar niches are considered exceptions to this law.

D.Cases in which the two species do not occupy that same niche yet still compete for the same resource are believed to be exceptions to this law.

10.According to paragraph 4,how does competition affect evolution?

A.It results in the evolution of physical structures that allow the species to compete with each other more effectively.

B.It results I the evolutionary extinction of all but one of the competing species.

C.It results in the competing species evolving in such a way that they no longer compete for the same resources.

D.It results in the competing species evolving to become so much like each other that competition between them eventually disappears.

11.According to paragraph 4,"species selection"is a misleading term because it

A.overemphasizes the role of selection pressure in species extinction.

B.suggests that selection pressures directly influence whole species.

C.does not make a distinction between species extinction and species evolution.

D.suggests that extinction always results whenever there is a competition.

12.The word"regulating"in the passage（paragraph 5）is closest in meaning to

A.controlling.

B.explaining.

C.observing.

D.stopping.

13.Look at the four squares[■]that indicate where the following sentence could be added to the passage.Where would the sentence best fit?That is,as the density of a population increases,competition has a greater impact and leads to greater mortality.

Competition may occur for any needed resource.

■【A】In the case of animals it is usually food;in the case of forest plants it may be light;in the case of substrate inhabitants it may be space,as in many shallow-waterbottom-dwelling marine organisms.

■【B】Indeed,it may be for any of the factors,physical as well as biotic,that are essential for organisms.

■【C】Competition isusually the more severe the denser the population.

■【D】Together with predation,itis the most important density-dependent factor in regulating population growth.

14.Directions:An introductory sentence for a brief summary of the passage is provided below.Complete the summary by selecting the THREE answer choices that express the most important ideas in the passage.Some sentences do not belong in the summary because they express ideas that are not presented in the passage or are minor ideas in the passage.This question is worth 2 points.

When necessary resources are limited,competition can occur among individuals of the same species or of different species.

A.Competition can eliminate a species,but since most species do not depend on a single resource,competition is often reduced by switching to alternative resources.

B.Investigation of the ecological role of competition is difficult because ordinarily the competition cannot be observed directly and must be inferred from its presumed effects.

C.Competition between a pair of species tends to lessen over time because the species tend to evolve to occupy different ecological niches and ranges.

D.Competition between individual of the same species is usually for food whereas competition between species is usually for habitat.

E.Experiments and field observation have established that competition between species is strong enough to prevent two species from occupying the same ecological niche.

F.Competition is usually strongest when the density of the competing populations is the same.

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