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2021年托业考试 阅读部分测试题 含答案解析

2021年托业考试 阅读部分测试题 含答案解析

The Role of Diapause

If conditions within an organism’s environment occasionally or regularly become harsh,it may

be advantageous for an organism to have a resistant stage built into the lifecycle. In such a

life history strategy, the organism suspends any growth, reproduction,or other activities for a

period of time so that they may occur at a later, more hospitable time. This genetically

determined resting stage, characterized by the cessation of development and protein

synthesis and suppression of the metabolic rate, is called diapause. Many other kinds of

resting stages, with different levels of suppression of physiological activities, are known. Some

of these resistant stages can be extremely long-lived. In one case, seeds of the arctic lupine,

a member of the pea family recovered from ancient lemming burrows in the Arctic,

germinated in three days even though they were carbon-dated at more than 10,000 years

old!

Unfavorable conditions that are relatively predictable probably pose a simpler problem for

organisms than do unpredictable conditions. Adaptations to the regular change of seasons

in the temperate and polar regions may be relatively simple. For example, many seeds require

a period of stratification, exposure to low temperatures for some minimum period, before

they will germinate. ■This is a simple adaptation to ensure that germination occurs following

the winter conditions rather than immediately prior to their onset. ■In contrast, unfavorable

conditions that occur unpredictably pose considerable problems for organisms. ■In fact,

unpredictability is probably a greater problem than is the severity of the unfavorable period.

■How can organisms cope with the unpredictable onset of good or poor conditions?

Many adaptations to this general problem are based on a resting stage that awaits

favorable conditions. We will consider two examples from the vertebrates. The first is

the red kangaroo. This marsupial inhabits the deserts of central Australia where the

onset of rains and the resulting sudden growth of vegetation are extremely

unpredictable. Obviously, it is advantageous for a kangaroo female to produce young

at a time when plant productivity is sufficient to support her offspring. For such a

relatively large mammal, however, gestation (the period of development during

2021年托业考试 阅读部分测试题 含答案解析

pregnancy) is so long that if a female waited to mate and carry the young until after

the rains came, the favorable period might be past. The kangaroo’s life history

adaptation to this problem involves the use of embryonic diapause during gestation

(development in the uterus).

After a 31-day gestation period, the female gives birth to a tiny helpless young typical

of marsupials. The newborn crawls into the mother’s pouch and attaches to a teat

where it continues to grow and develop. After 235 days it leaves the pouch but remains

with the mother and obtains milk from her. Two days after giving birth, the female mates

again. The fertilized egg enters a 204-day period of embryonic diapause during which it

remains in the uterus but does not attach. It then implants, and 31 days later, birth of the

second young occurs. Note that the first young leaves the pouch at just this time. Again,

the female mates, fertilization occurs, and another diapause follows. The eventual result

is that at any one time, the female has three young at various stages of development:

one in diapause, one in the pouch, and one outside the pouch. Among other benefits,

this allows her to freeze the development of an embryo during times of drought and food

shortage until the offspring in the pouch is able to leave.

A similar strategy—accelerated development combined with a resting stage—has also

allowed amphibians to inhabit deserts. The spadefoot toads, such as Couch’s spadefoot

toad, inhabit some of the most severe deserts in North America. Adults of this species

burrow deeply into the substrate where it is cooler and perhaps more moist. Here they

enter into a resting state in which they are covered with a protective layer of dead skin.

When it rains, the adults emerge and congregate to mate at temporary ponds.

Development is greatly accelerated: the eggs hatch within 48 hours, and the tadpoles

change into toads at 16-18 days. Consequently, they can complete the life cycle during

the brief window of favorable conditions, then return to the resistant resting stage to

await the next rainfall. Resting stages thus comprise a series of adaptations that allow

the species to avoid the most difficult conditions for life.

1. According to paragraph 1, why do some organisms have a resting stage during

their life cycle?

▢ To recover from injuries suffered during harsh conditions

2021年托业考试 阅读部分测试题 含答案解析

▢ To devote all of their energy to a period of growth and reproduction

▢ To wait for local conditions to become favorable for important life events

▢ To prepare to move to a different environment if conditions become harsh

2. Why does the author mention “seeds of the arctic lupine”?

▢ To argue that members of the pea family are extremely resistant to cold

temperature

▢ To provide information about what ancient lemmings ate during their long resting

periods

▢ To provide an example of an organism with a resting stage that has many

different levels of suppression of physiological activities

▢ To support that some resting stages last an extremely long time.

3. According to paragraph 2, why do many seeds require a period of

stratification?

▢ To slowly build up a tolerance for lower and lower temperatures

▢ To guarantee that the seeds grow after and not before unfavorable weather

▢ To make sure that the seeds can deal with unpredictable conditions

▢ To give the seeds enough time to germinate before winter.

4. Paragraph 4 supports all of the following statements about the red kangaroo of

central Australia EXCEPT:

▢ A female kangaroo mates again shortly after her newborn enters her pouch.

▢ During diapause, a young kangaroo stays in the female’s pouch and growth of a

second fertilized egg inside the uterus is delayed.

▢ To put different young kangaroos at various stages of development is

advantageous for the female kangaroo to handle them at the same time.

▢ The pause of the development of an embryo has more benefits for preparing it to

avoid the harsh times than for competing with its siblings.

5. What is the main purpose of paragraph 4 in the passage?

▢ To give the details of an adaptation mentioned in paragraph 3

▢ To describe an adaptation different from the one explained in paragraph 3

▢ To introduce an adaptation that is described in detail in paragraph 5

2021年托业考试 阅读部分测试题 含答案解析

▢ To discuss an adaptation that is set as successful as the one mentioned before.

6. The word “comprise” in the passage is closest in meaning to

▢ consist of

▢ bring about

▢ are similar to

▢ take the place of

7. According to paragraph 5, how do amphibians such as spadefoot toads survive

the severe heat conditions in the North American deserts?

▢ They dig down into the ground and go into a resistant resting state.

▢ They remain in the ponds that develop after it has rained.

▢ They lose their outer layer of skin.

▢ Their eggs live dormant until the desert air becomes cooler and more moist.

8. According to paragraph 5, which of the following occurs during the life cycle of

the spadefoot toad?

▢ The female’s eggs hatch under the surface of the desert.

▢ The adults mate during the dry period.

▢ The newborn grows into an adult before unfavorable conditions return.

▢ The newborn enters a resting stage before it becomes an adult.

9. Look at the four squares [■ ] that indicate where the following sentence can be

added to the passage.

Such adaptations to predictable conditions can also be made by animals,

such as by hibernating during the coldest months.

Where would the sentence best fit? Click on a square [■ ] to add the sentence

to the passage.

10. 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 answer

choices 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. Drag your choices to the spaces where they belong. To review the

2021年托业考试 阅读部分测试题 含答案解析

passage, click on View Text.

Some organisms adapt to periodic harsh conditions by building a resistant

stage, or diapause, into their life cycle.

● ● ●

Answer choices

1. The diapause stage evolved very early and is most common in species that first

appeared more than 10,000 years ago

2. Unpredictable conditions are more problematic for organisms than are predictable

changes such as the seasons.

3. Some seeds may germinate in three days even if they have been exposed to very

low temperatures for a long time.

4. Some marsupials can care for three newborns in their pouch at the same time,

allowing the young to leave the pouch only when conditions are favorable for their

growth.

5. The female red kangaroo adapts to unfavorable conditions by delaying the

development of the embryo in the uterus.

6. Some amphibians adapt to arid environments by completing accelerated

development with resting stages deep underground.

The Plow and the Horse in Medieval Europe

One of the most important factors driving Europe’s slow emergence from the economic

stagnation of the Early Middle Ages (circa 500-1000 B.C.E.) was the improvement of

agricultural technology. One innovation was a new plow, with a curved attachment

(moldboard) to turn over wet, heavy soils, and a knife (or coulter) in front of the blade to

allow a deeper and easier cut. ■This more complex plow replaced the simpler “scratch”

plow that merely made a shallow, straight furrow in the ground. ■In the lands around

the Mediterranean, with light rains and mild winters, this had been find, but in the wetter

terrain north and west of the Danube and the Alps, such a plow left much to be desired,

and it is to be wondered if it was used at all. ■Cleared lands would more likely have

been worked by hand tilling, with little direct help from animals, and the vast forests

natural to Northern Europe remained either untouched, or perhaps cleared in small

2021年托业考试 阅读部分测试题 含答案解析

sections by fire, and the land probably used only so long as the ash-enriched soil

yielded good crops and then abandoned for some others similarly cleared field. ■Such

a pattern of agriculture and settlement was no basis for sustained cultural or economic

life.

With the new heavy plow, however, fields could be cleared, sowed, and maintained with

little more difficulty than in the long-settled lands of Southern Europe, while the richness

of the new soils, the reliability of the rains, and the variety of crops now possible made

for an extremely productive agriculture. The new tool, however, imposed new demands,

technical, economic, and social. The heavy plow was a substantial piece of capital,

unlike a simple hand hoe, and this had the same sorts of implications that capitalization

always has—it favored the concentration of wealth and control. Moreover, making full

use of it required more animal power, and this had a host of implications of its own. The

full importance of this was even more apparent in the centuries after 1000, when oxen

began to give way in certain parts of Western Europe to horses.

The powerful, rugged farm horse was itself a product of improvement during the Middle

Ages, and it was part of a complex set of technical changes and capabilities. The

introduction of new forms of equipment for horses transformed this animal into the

single most important assist to human labor and travel. Instead of the old harness used

by the ancient Greeks and Romans, there appeared from Central Asia the rigid, padded

horse collar. Now, when the horse pulled against a load, no longer did the load pull back

against its neck and windpipe but rather rode on the sturdy shoulders. When this

innovation was combined with the iron horseshoe, the greater speed and stamina of the

horse displaced oxen wherever it could be afforded. The larger importance of this lay

not only in more efficient farmwork, but in swifter and surer transportation between town

and countryside. The farmer with horses could move products to market more

frequently and at greater distances than with only oxen, and the urban development that

was to transform the European economic and social landscape after the eleventh

century was propelled in large part by these new horse-centered transport capabilities.

Another indicator of how compelling and important was the new horse agriculture was

its sheer cost. Unlike oxen and other cattle, horses cannot be supported exclusively on

2021年托业考试 阅读部分测试题 含答案解析

hay and pasturage, they require, particularly in northern climates where pasturing

seasons are short, cropped food, such as oats and alfalfa. Unlike grass and hay, these

are grown with much of the same effort and resources applied to human nourishment,

and thus their acquisition represents a sacrifice, in a real sense, of human food. The

importance of this in a world that usually lived at the margins of sufficient diet is hard to

overstate. The increased resources that went into making the horse central to both the

medieval economy and, in a separate but related development, medieval warfare, are

the surest signs of the great utility the animal now assumed.

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

▢ instability

▢ lack of growth

▢ dependence on others

▢ decline

2. According to paragraph 1, what was the main advantage of the new plow over

the scratch plow?

▢ The new plow created straighter rows.

▢ The new plow was easier for animals to pull.

▢ The new plow could dig deeper into the soil.

▢ The new plow was easier to make.

3. The word “sustained” in the passage is closest in meaning to

▢ continued

▢ established

▢ ordinary

▢ active

4. According to paragraph 1, the scratch plow was particularly unsuited to

▢ the lands around the Mediterranean

▢ places where the soil was often dry

▢ places where land was cleared and worked by hand

▢ places where the soil was particularly wet and heavy

5. Paragraph 1 implies which of the following about agriculture before the

2021年托业考试 阅读部分测试题 含答案解析

introduction of the new plow?

▢ Limited rainfall had prevented large-scale agricultural development.

▢ Most of Europe’s developed agricultural communities were located in the south.

▢ Several other important innovations immediately preceded the development of

the new plow.

▢ Much of Europe’s forestland had been converted to agricultural use.

6. What can be inferred from the information that the new plow “favored the

concentration of wealth and control”?

▢ Wealthy farmers in the south had a significant economic advantage over farmers

in the north.

▢ The production and sale of the new plow became an important source of capital.

▢ The new plow was more popular in parts of Europe where oxen were used for

farming than in parts where horses were used.

▢ Greater economic equality existed in northern Europe before the introduction of

the new plow.

7. According to paragraph 3, which of the following contributed to the dramatic

rise in the agricultural use of horses in Europe?

▢ Apowerful new breed of farm horse was brought to Europe from Central Asia.

▢ Farmers began using rigid, padded collars that allowed horses to pull heavy loads

more easily.

▢ For the first time, horses became cheaper than oxen.

▢ Farmers began studying the farming techniques used by the horse-drawn plows.

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

▢ cheaply

▢ easily

▢ reliably

▢ solely

9. Look at the four squares [■ ] that indicate where the following sentence can be

added to the passage.

In fact, it sliced the ground so thoroughly that fields could be planted after

2021年托业考试 阅读部分测试题 含答案解析

only one plowing rather than the two needed before.

Where would the sentence best fit? Click on a square [■ ] to add the sentence

to the passage.

10. 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 answer

choices 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. Drag your choices to the spaces where they belong. To review the

passage, click on View Text.

Agricultural innovations with important social and economic consequences

occurred in eleventh-century Europe.

●

Answer Choices

1. Light rains and unpredictable winters had made most of the soil in Europe unsuitable

for enough agriculture to sustain economic development.

2. Farmers switched from oxen to horses to pull their plows because inexpensive

pasturage for oxen decreased significantly in the centuries after 1000 B.C.E.

3. The introduction of iron horseshoes enabled farmers to transport goods

farther than they could with the more expensive oxen.

4. Improvements in the design of plows opened up vast areas of land in Northern

Europe that had previously been unusable for sustained agriculture.

5. With help from a new kind of harness from Asia, horses were able to pull the new

heavy plow and to transport goods to market more quickly and frequently.

6. The horse came to be valued so greatly that farmers devoted some of their land to

growing crops for their horses rather than using this land to grow food for their

families.

The Origins of Plant and Animal Domestication

The emergence of plant and animal domestication represented a monumental change

in the ways that humans interacted with Earth’s resources: the rate at which Earth’s

2021年托业考试 阅读部分测试题 含答案解析

surface was modified and the rates of human population growth. The development of

agriculture was accompanied by fundamental changes in the organization on human

society: disparities in wealth, hierarchies of power, and urbanization.

Phrases like “plant and animal domestication” and “the invention of agriculture” create

the impression that humans made the transition to cultivating plants and tending

animals rather abruptly, maybe with a flash of insight. Most scholars don’t think so. It

seems more likely that humans used and manipulated wild plants and animals for many

hundreds of thousands of years. The transition to gardens, fields, and pastures was

probably gradual, the natural outgrowth of a long familiarity with the environmental

requirements, growth cycles, and reproductive mechanisms of whatever plants and

animals humans liked to eat, ride, or wear.

For years, scholars argued that the practices of cultivation and animal domestication

were invented in one or two locations on Earth and then diffused from those centers of

innovation. ■ Genetic studies are now showing that many different groups of people in

many different places around the globe learned independently to create especially

useful plants and animals through selective breeding. ■Probably both independent

invention and diffusion played a role in agricultural innovation. ■Sometimes the ideas

of domestication and cultivation were relayed to new places. In other cases the farmers

or herders themselves moved into new zones, taking agriculture or improvements such

as new tools or new methods or new plants and animals with them. ■

Scholars used to assume that people turned to cultivating instead of gathering their food

either because they had to in order to feed burgeoning populations, or because

agriculture provided such obviously better nutrition. It now seems that neither of these

explanations is valid. First of all, the risk at tached to exploring new food sources when

there were already too many mouths to feed would be too great. Second, agriculture did

not necessarily improve nutrition or supplies of food. A varied diet based on gathered

(and occasionally hunted) food probably provided a wider, more secure range of

nutrients than an early agriculturally based diet of only one or two cultivated crops. More

likely, populations expanded after agricultural successes, and not before.

Richard MacNeish, an archaeologist who studied plant domestication in Mexico and