Câu hỏi:

19/07/2024 127

Read the following text and mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the questions.

Many ants forage across the countryside in large numbers and undertake mass migrations; these activities proceed because one ant lays a trail on the ground for the others to follow. As a worker ant returns home after finding a source of food, it marks the route by intermittently touching its stinger to the ground and depositing a tiny amount of trail pheromone – a mixture of chemicals that delivers diverse messages as the context changes. These trails incorporate no directional information and may be followed by other ants in either direction.

Unlike some other messages, such as the one arising from a dead ant, a food trail has to be kept secret from members of other species. It is not surprising then that ant species use a wide variety of compounds as trail pheromones. Ants can be extremely sensitive to these signals. Investigators working with the trail pheromone of the leafcutter ant Atta texana calculated that one milligram of this substance would suffice to lead a column of ants three times around Earth.

The vapor of the evaporating pheromone over the trail guides an ant along the way, and the ant detects this signal with receptors in its antennae. A trail pheromone will evaporate to furnish the highest concentration of vapor right over the trail, in what is called a vapor space. In following the trail, the ant moves to the right and left, oscillating from side to side across the line of the trail itself, bringing first one

and then the other antenna into the vapor space. As the ant moves to the right, its left antenna arrives in the vapor space.

The signal it receives causes it to swing to the left, and the ant then pursues this new course until its right antenna reaches the vapor space. It then swings back to the right, and so weaves back and forth down the trail.

What does the passage mainly discuss?

A. The information contained in pheromones           

B. The mass migration of ants

C. How ants mark and follow a chemical trail          

Đáp án chính xác

D. Different species of ants around the world

Trả lời:

verified Giải bởi Vietjack

Đoạn văn chủ yếu thảo luận gì?

A. Thông tin chứa trong pheromones

C. Làm thế nào kiến đánh dấu và đi theo một dấu vết hóa học

B. Sự di cư rất đông của kiến

D. Các loài kiến khác nhau trên thế giới

Chọn đáp án là C

CÂU HỎI HOT CÙNG CHỦ ĐỀ

Câu 1:

. Read the following passage and mark the letter A, B, C, or D on your answer sheet to choose the best answer for the following questions.

In the past, both men and women were expected to be married at quite young ages. Marriages were generally arranged by parents and family, with their children having little chance to say no in the matter. In the past it was not surprising to find that a bride and groom had only just met on the day of their engagement or marriage.

In modern Vietnam, this has changed completely as people choose their own marriage-partners based on love, and in consideration primarily to their own needs and wants. Moreover early marriage is quite illegal.

The traditional Vietnamese wedding is one of the most important of traditional Vietnamese occasions. Regardless of westernization, many of the age-old customs practiced in a traditional Vietnamese wedding continue to be celebrated by both Vietnamese in Vietnam and overseas, often combining both western and eastern elements. Besides the wedding ceremony, there is also an engagement ceremony which takes place usually half a year or so before the wedding. Due to the spiritual nature of the occasion, the date and time of the marriage ceremony are decided in advance by a fortune teller. The traditional Vietnamese wedding consists of an extensive array of ceremonies: the first is the ceremony to ask permission to receive the bride, the second is the procession to receive the bride (along with the ancestor ceremony at her house), the third is to bring the bride to the groom's house for another ancestor ceremony and to welcome her into the family, then the last is a wedding banquet. The number of guests in attendance at these banquets is huge, usually in the hundreds. Several special dishes are served. Guests are expected to bring gifts, often money, which the groom and bride at one point in the banquet will go from table to table collecting.

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Câu 2:

The expression pass themselves off as in paragraph 2 means ____.

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Câu 3:

The word “array” in paragraph 3 is closest in meaning to _______.

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Câu 4:

The underlined phrase “the trend of” in paragraph 1 could be best replaced by which of the following?

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Câu 5:

The word “banquet” in paragraph 3 is closest in meaning to _______.

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Câu 6:

According to the first paragraph, which group is most likely to be worried about children’s use of the Internet?

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Câu 7:

Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the questions.

After two decades of growing student enrollments and economic prosperity, business schools in the United States have started to face harder times. Only Harvard's MBA School has shown a substantial increase in enrollment in recent years. Both Princeton and Stanford have seen decreases in their enrollments. Since 1990, the number of people receiving Masters in Business Administration (MBA) degrees, has dropped about 3 percent to 75,000, and the trend of lower enrollment rates is expected to continue.

There are two factors causing this decrease in students seeking an MBA degree. The first one is that many graduates of four-year colleges are finding that an MBA degree does not guarantee a plush job on Wall Street, or in other financial districts of major American cities. Many of the entry-level management jobs are going to students graduating with Master of Arts degrees in English and the humanities as well as those holding MBA degrees. Students have asked the question, "Is an MBA degree really what I need to be best prepared for getting a good job?" The second major factor has been the cutting of American payrolls and the lower number of entry-level jobs being offered. Business needs are changing, and MBA schools are

struggling to meet the new demands.

 What does the passage mainly discuss?        

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Câu 8:

It seems that the main point the author is trying to make about the Internet is that it _____.

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Câu 9:

The phrase "subject to" in line 1 is closest in meaning to

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Câu 10:

The underlined word “plush” in paragraph 2 is closest in meaning to which of the following?

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Câu 11:

According to the passage, which of the following is true about the traditional Vietnamese

wedding?

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Câu 12:

In former days, the fact that a bride and groom had only first met just on the day of their engagement or marriage was _________.

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Câu 13:

According to the passge, which does not exist in a Vietnamese wedding party?

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Câu 14:

The word “intermittently” in paragraph 1 is closest in meaning to

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Câu 15:

The underlined word “one” in paragraph 2 most likely refers to

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