11月12日托福阅读答案解析

托福阅读考试中出现的背景知识包括生物类环境对于动物的影响、地质类讲述北美迁徙鸟类的相关内容。那么下面和小编来看看这篇11月12日托福阅读答案解析，一定会有收获。

11月12日托福阅读答案解析

1. 学科分类：生物类

题目：The origin of plants and animal domestication

内容回忆：本文共6段。第一段介绍 plants and animal domestication的概念。第二段写一般学者认为plants and animal domestication只在一两个地区形成，后面传播到其他地区。但后面基因研究证明，各个地区都有独立的生物驯化，通过selective breeding。所以是独立驯化和diffusion一起导致其传播。第三写人们认为人们驯化生物是为了应对增长的人口和提高食物的营养。但后来研究表明其实是驯化生物之后，人口才进一步增长，并提高人们的营养成分。

第四段写R教授对于plants and animal domestication目的的研究，是为了trading for new information 和满足生存需求。第六段E.N教授进一步之处plants and animal domestication引发的全球性问题，包括环境、财富不均、人口增长等问题。

2. 学科分类：文化艺术

题目：Dutch Painting

内容回忆：本文共5段。第一段说17世纪是荷兰艺术文化的黄金时期，画作主要以花草，任务，事件为主题，具备道德宣扬和法律记录的作用。第二段说画作采用text information的方式标明所属对象等真实性。第三段说这种方式同样能够体现出画作的主要内容以及作者的意图。第四段举了一个例子，Heyden的“room corner curiosity”主要传达了万物皆空的理念。第五段说后期规范之后的书写方式使得欧洲文明大放异彩

词汇题：

1. typically：specifically

2. thus: as a result

3. pursuit: possession

4. intricate: complex

Passage Two

3. 学科分类：植物

题目：Determination of Plant Diversity in a Particular Place

内容回忆：本文共5段。第1段说植物多样性会因为历史原因减少例如海平面降低;第2段提出第二个原因physiological traits;第3段揭露第三个原因biotic interaction;第四段说以上三种原因会不断变化，相互作用但biotic interaction是最主要引起多样性骤减的因素。第五段提出为什么在不同区域植物多样性会呈现不同情况的原因，在热带雨林主要是由light climate引起的;而在沙原(sand plains)则是root traits 导致的。

4. 学科分类：生物

题目：The role of diapause

内容回忆：第1段介绍生物为了应对环境变化，会暂停调整生命阶段的某个环境，比如生长和繁殖等去应对环境。举例讲了一个一万年前的极地种子，挖掘后在三天内还可发芽。第二段介绍可预期和不可预期环境变化对生物的影响。其中，不可预期影响更大。第三段和第四段用澳洲的红袋鼠举例。母袋鼠生产后一两天后就会交配，产生胚胎。而同时育儿袋中还会有幼儿发育。已经生产出来的幼年袋鼠还会依靠母乳生长。所以母袋鼠繁殖期间，会同时照顾三个阶段的幼儿。从而应对环境的影响。第五段以蟾蜍为例，讲解两栖动物会应对干旱而加快生长期。

Passage Three

5. 学科分类：地质

题目：Explaining declination in migratory birds populations

内容回忆：第1段讲北美迁徙类鸟类的数量下降，大部分鸟类数量减少，有的鸟类数量增长。第二段讲栖息地变化对鸟类数量的影响。第三段讲cowbirds对其他migratory birds的影响。Cowbirds会把自己的鸟蛋放到别的鸟窝之中，让它们孵化。第三段讲cowbirds对migratory birds影响比predator对这些鸟的危害还有大。因为migratory birds不知道cowbirds的存在，会继续帮它们抚养幼鸟。但它们会懂得躲避predator。所以有的migratory birds的数量会下降。第四段讲栖息地减少对migratory birds的影响。

6. 学科分类：农业

题目：Inca Highlands Adaptation

内容回忆：本文共5段。第1段讲highlands繁荣的经济主要是以农业和畜牧业为主。第2段说高低的农业发展会遇到很多挑战例如：雨水;霜冻，冰雹;土壤肥沃程度。第3段提到当地农民发明了一些方法去解决以上问题。第一种是verticality，在不同海拔高度相邻的地方种植各种不同的作物.第4段是第二种方法，通过风干技术储存在产量丰收年的粮食。第5段给出最后一种方法，组织一群人去较远的地方种植当地不能产的作物，等到成熟采用船运回。由此形成了各种分布较散的殖民地。

Passage Four

7. 学科分类：人文

题目：Population Evolution in 18th Europe

内容回忆：本文共5段。第一段说明欧洲从美洲引进了新的食物——土豆(potato)，政府支持大范围种植以以此为经济和军事发展所需的劳动力提供粮食。第二段说当地农民改善作物使用，农具以及畜牧业的养殖方法使得农业发展非常繁荣。第三段说经济的迅速发展使得欧洲人口大增，从188million——400million。第四段说人口暴增打破了传统出生率和死亡率的平衡。第五段说健康充分的食物以及传染病的减少使新生儿数量增多，从而增加了更多劳动力从事生产。但其中死亡率的降低是维持人口增长的主导因素。

托福阅读真题：The Long-Term Stability of Ecosystems

Plant communities assemble themselves flexibly, and their particular structure depends on the specific history of the area. Ecologists use the term “succession” to refer to the changes that happen in plant communities and ecosystems over time. The first community in a succession is called a pioneer community, while the long-lived community at the end of succession is called a climax community. Pioneer and successional plant communities are said to change over periods from 1 to 500 years. These changes—in plant numbers and the mix of species—are cumulative. Climax communities themselves change but over periods of time greater than about 500 years.

An ecologist who studies a pond today may well find it relatively unchanged in a year’s time. Individual fish may be replaced, but the number of fish will tend to be the same from one year to the next. We can say that the properties of an ecosystem are more stable than the individual organisms that compose the ecosystem.

At one time, ecologists believed that species diversity made ecosystems stable. They believed that the greater the diversity the more stable the ecosystem. Support for this idea came from the observation that long-lasting climax communities usually have more complex food webs and more species diversity than pioneer communities. Ecologists concluded that the apparent stability of climax ecosystems depended on their complexity. To take an extreme example, farmlands dominated by a single crop are so unstable that one year of bad weather or the invasion of a single pest can destroy the entire crop. In contrast, a complex climax community, such as a temperate forest, will tolerate considerable damage from weather to pests.

The question of ecosystem stability is complicated, however. The first problem is that ecologists do not all agree what “stability” means. Stability can be defined as simply lack of change. In that case, the climax community would be considered the most stable, since, by definition, it changes the least over time. Alternatively, stability can be defined as the speed with which an ecosystem returns to a particular form following a major disturbance, such as a fire. This kind of stability is also called resilience. In that case, climax communities would be the most fragile and the least stable, since they can require hundreds of years to return to the climax state.

Even the kind of stability defined as simple lack of change is not always associated with maximum diversity. At least in temperate zones, maximum diversity is often found in mid-successional stages, not in the climax community. Once a redwood forest matures, for example, the kinds of species and the number of individuals growing on the forest floor are reduced. In general, diversity, by itself, does not ensure stability. Mathematical models of ecosystems likewise suggest that diversity does not guarantee ecosystem stability—just the opposite, in fact. A more complicated system is, in general, more likely than a simple system to break down. A fifteen-speed racing bicycle is more likely to break down than a child’s tricycle.

Ecologists are especially interested to know what factors contribute to the resilience of communities because climax communities all over the world are being severely damaged or destroyed by human activities. The destruction caused by the volcanic explosion of Mount St. Helens, in the northwestern United States, for example, pales in comparison to the destruction caused by humans. We need to know what aspects of a community are most important to the community’s resistance to destruction, as well as its recovery.

Many ecologists now think that the relative long-term stability of climax communities comes not from diversity but from the “patchiness” of the environment, an environment that varies from place to place supports more kinds of organisms than an environment that is uniform. A local population that goes extinct is quickly replaced by immigrants from an adjacent community. Even if the new population is of a different species, it can approximately fill the niche vacated by the extinct population and keep the food web intact.

Paragraph 1: Plant communities assemble themselves flexibly, and their particular structure depends on the specific history of the area. Ecologists use the term “succession” to refer to the changes that happen in plant communities and ecosystems over time. The first community in a succession is called a pioneer community, while the long-lived community at the end of succession is called a climax community. Pioneer and successional plant communities are said to change over periods from 1 to 500 years. These changes—in plant numbers and the mix of species—are cumulative. Climax communities themselves change but over periods of time greater than about 500 years.

托福阅读真题题目

1. The word “particular” in the passage is closest in meaning to

○Natural

○Final

○Specific

○Complex

2. According to paragraph 1, which of the following is NOT true of climax communities?

○They occur at the end of a succession.

○They last longer than any other type of community.

○The numbers of plants in them and the mix of species do not change.

○They remain stable for at least 500 years at a time.

Paragraph 2: An ecologist who studies a pond today may well find it relatively unchanged in a year’s time. Individual fish may be replaced, but the number of fish will tend to be the same from one year to the next. We can say that the properties of an ecosystem are more stable than the individual organisms that compose the ecosystem.

3. According to paragraph 2, which of the following principles of ecosystems can be learned by studying a pond?

○Ecosystem properties change more slowly than individuals in the system.

○The stability of an ecosystem tends to change as individuals are replaced.

○Individual organisms are stable from one year to the next.

○A change in the members of an organism does not affect an ecosystem’s properties

Paragraph 3: At one time, ecologists believed that species diversity made ecosystems stable. They believed that the greater the diversity the more stable the ecosystem. Support for this idea came from the observation that long-lasting climax communities usually have more complex food webs and more species diversity than pioneer communities. Ecologists concluded that the apparent stability of climax ecosystems depended on their complexity. To take an extreme example, farmlands dominated by a single crop are so unstable that one year of bad weather or the invasion of a single pest can destroy the entire crop. In contrast, a complex climax community, such as a temperate forest, will tolerate considerable damage from weather of pests.

4. According to paragraph 3, ecologists once believed that which of the following illustrated the most stable ecosystems?

○Pioneer communities

○Climax communities

○Single-crop farmlands

○Successional plant communities

Paragraph 4: The question of ecosystem stability is complicated, however. The first problem is that ecologists do not all agree what “stability” means. Stability can be defined as simply lack of change. In that case, the climax community would be considered the most stable, since, by definition, it changes the least over time. Alternatively, stability can be defined as the speed with which an ecosystem returns to a particular form following a major disturbance, such as a fire. This kind of stability is also called resilience. In that case, climax communities would be the most fragile and the least stable, since they can require hundreds of years to return to the climax state.

5. According to paragraph 4, why is the question of ecosystem stability complicated?

○The reasons for ecosystem change are not always clear.

○Ecologists often confuse the word “stability” with the word “resilience.”

○The exact meaning of the word “stability” is debated by ecologists.

○There are many different answers to ecological questions.

6. According to paragraph 4, which of the following is true of climax communities?

○They are more resilient than pioneer communities.

○They can be considered both the most and the least stable communities.

○They are stable because they recover quickly after major disturbances.

○They are the most resilient communities because they change the least over time.

Paragraph 5: Even the kind of stability defined as simple lack of change is not always associated with maximum diversity. At least in temperate zones, maximum diversity is often found in mid-successional stages, not in the climax community. Once a redwood forest matures, for example, the kinds of species and the number of individuals growing on the forest floor are reduced. In general, diversity, by itself, does not ensure stability. Mathematical models of ecosystems likewise suggest that diversity does not guarantee ecosystem stability—just the opposite, in fact. A more complicated system is, in general, more likely than a simple system to break down. (A fifteen-speed racing bicycle is more likely to break down than a child’s tricycle.)

7. Which of the following can be inferred from paragraph 5 about redwood forests?

○They become less stable as they mature.

○They support many species when they reach climax.

○They are found in temperate zones.

○They have reduced diversity during mid-successional stages.

8. The word “guarantee” in the passage is closest in meaning to

○Increase

○Ensure

○Favor

○Complicate

9. In paragraph 5, why does the author provide the information that “(A fifteen-speed racing bicycle is more likely to break down than a child’s tricycle)”?

○To illustrate a general principle about the stability of systems by using an everyday example

○To demonstrate that an understanding of stability in ecosystems can be applied to help understand stability in other situations

○To make a comparison that supports the claim that, in general, stability increases with diversity

○To provide an example that contradicts mathematical models of ecosystems

Paragraph 6: Ecologists are especially interested to know what factors contribute to the resilience of communities because climax communities all over the world are being severely damaged or destroyed by human activities. The destruction caused by the volcanic explosion of Mount St. Helens, in the northwestern United States, for example, pales in comparison to the destruction caused by humans. We need to know what aspects of a community are most important to the community’s resistance to destruction, as well as its recovery.

10. The word “pales” in the passage is closest in meaning to

○Increases proportionally

○Differs

○Loses significance

○Is common

Paragraph 7：Many ecologists now think that the relative long-term stability of climax communities comes not from diversity but from the “patchiness” of the environment, an environment that varies from place to place supports more kinds of organisms than an environment that is uniform. A local population that goes extinct is quickly replaced by immigrants from an adjacent community. Even if the new population is of a different species, it can approximately fill the niche vacated by the extinct population and keep the food web intact.

11.Which of the sentences below best expresses the essential information in the highlighted sentence in the passage? Incurred choices change the meaning in important ways or leave out essential information.

○Ecologists now think that the stability of an environment is a result of diversity rather than patchiness.

○Patchy environments that vary from place to place do not often have high species diversity.

○Uniform environments cannot be climax communities because they do not support as many types of organisms as patchy environments.

○A patchy environment is thought to increase stability because it is able to support a wide variety of organisms.

12.The word “adjacent” in the passage is closest in meaning to

○Foreign

○Stable

○Fluid

○Neighboring

Paragraph 6: Ecologists are especially interested to know what factors contribute to the resilience of communities because climax communities all over the world are being severely damaged or destroyed by human activities. The destruction caused by the volcanic explosion of Mount St. Helens, in the northwestern United States, for example, pales in comparison to the destruction caused by humans. We need to know what aspects of a community are most important to the community’s resistance to destruction, as well as its recovery.

13.Look at the four squares [ ] that indicate where the following sentence could be added to the passage.

In fact, damage to the environment by humans is often much more severe than damage by natural events and processes.

Where would the sentence best fit? Click on a square to add the sentence to the passage.

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.

The process of succession and the stability of a climax community can change over time.

Answer choices

○The changes that occur in an ecosystem from the pioneer to the climax community can be seen in one human generation.

○A high degree of species diversity does not always result in a stable ecosystem.

○The level of resilience in a plant community contributes to its long-term stability.

○Ecologists agree that climax communities are the most stable types of ecosystems.

○Disagreements over the meaning of the term “stability” make it difficult to identify the most stable ecosystems.

○The resilience of climax communities makes them resistant to destruction caused by humans.

托福阅读真题参考答案

1. ○3　2. ○3　3. ○1　4. ○2　5. ○3　6. ○2　7. ○3　8. ○2　9. ○1　10. ○3　11. ○4　12. ○4　13. ○2　14. ○2 3 5