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Read the following passage and mark the letter A, B, C or D to indicate the correct answer to each of the questions from 43 to 50.

It is estimated that over 99 percent of all species that ever existed have become extinct. What causes extinction? When a species is no longer adapted to a changed environment, it may perish. The exact causes of a species' death vary from situation to situation. Rapid ecological change may render an environment hostile to a species. For example, temperatures may change and a species may not be adapted. Food resources may be affected by environmental changes, which will then cause problems for a species requiring these resources. Other species may become better adapted to an environment, resulting in competition and, ultimately, in the death of a species.

The fossil record reveals that extinction has occurred throughout the history of Earth. Recent analyses have also revealed that on some occasions many species became extinct at the same time - a mass extinction. One of the best-known examples of mass extinction occurred 65 million years ago with the demise of dinosaurs and many other forms of life. Perhaps the largest mass extinction was the one that occurred 225 million years ago, when approximately 95 percent of all species died. Mass extinctions can be caused by a relatively rapid change in the environment and can be worsened by the close interrelationship of many species. If, for example, something were to happen to destroy much of the plankton in the oceans, then the oxygen content of Earth would drop, even affect organisms not living in the oceans. Such a change would probably lead to a mass extinction.

One interesting, and controversial, finding is that extinctions during the past 250 million years have tended to be more intense every 26 million years. The periodic extinction might be due to intersection of the earth's orbit with a cloud of comets, but this theory is purely speculative. Some researchers have also speculated that extinction may often be random. That is, certain species may be eliminated and others may survive for no particular reason. A species' survival may have nothing to do with its ability or inability to adapt. If so, some of revolutionary history may reflect a sequence of essentially random events.

Question 49: Which of the following can be inferred from the theory of periodic extinction mentioned in paragraph 3?

A. many scientists could be expected to disagree with it.

B. most scientists believe the theory to be accurate.

C. the theory is no longer seriously considered.

D. evidence to support the theory has recently been found.

1
5 tháng 11 2018

Đáp án A

Dịch nghĩa: Từ học thuyết tuyệt chủng chu kì được đề cập ở đoạn 3 có thể suy ra điều gì?

A. rất nhiều nhà khoa học có thể phản đối nó.

B. hầu hết các nhà khoa học tin học thuyết này là đúng.

C. học thuyết này không còn được xem xét một cách nghiêm túc nữa.

D. bằng chứng để ủng hộ học thuyết này đã được tìm ra.

Giải thích: Thông tin nằm ở “The periodic extinction might be due to intersection of the earth’s orbit with a cloud of comets, but this theory is purely speculative”. Vì nó hoàn toàn là suy đoán nên ta có thể suy đoán rằng nó bị nhiều nhà khoa học khác phản đối.

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.It is estimated that over 99 percent of all species that ever existed have become extinct. What causes extinction? When a species is no longer adapted to a changed environment, it may perish. The exact causes of a species’ death vary from situation to situation. Rapid ecological change may render an environment hostile to a species. For example,...
Đọc tiếp

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.

It is estimated that over 99 percent of all species that ever existed have become extinct. What causes extinction? When a species is no longer adapted to a changed environment, it may perish. The exact causes of a species’ death vary from situation to situation. Rapid ecological change may render an environment hostile to a species. For example, temperatures may change and a species may not be adapted. Food resources may be affected by environmental changes, which will then cause problems for a species requiring these resources. Other species may become better adapted to an environment, resulting in competition and, ultimately, in the death of a species.

The fossil record reveals that extinction has occurred throughout the history of  Earth. Recent analyses have also revealed that on some occasions many species became extinct at the same time - a mass extinction. One of the best-known examples of mass extinction occurred 65 million years ago with the demise of dinosaurs and many other forms of life. Perhaps the largest mass extinction was the one that occurred 225 million years ago, when approximately 95 percent of all species died. Mass extinctions can be caused by a relatively rapid change in the environment and can be worsened by the close interrelationship of many species. If, for example, something were to happen to destroy much of the plankton in the oceans, then the oxygen content of Earth would drop, even affect organisms not living in the oceans. Such a change would probably lead to a mass extinction.

One interesting, and controversial, finding is that extinctions during the past 250 million years have tended to be more intense every 26 million years. The periodic extinction might be due to intersection of the earth’s orbit with a cloud of comets, but this theory is purely speculative. Some researchers have also speculated that extinction may often be random. That is, certain species may be eliminated and others may survive for no particular reason. A species’ survival may have nothing to do with its ability or inability to adapt. If so, some of revolutionary history may reflect a sequence of essentially random events.

Which of the following is NOT mentioned in paragraph 1 as resulting from rapid ecological change?

A. Temperature changes                                          

B. Introduction of new species

C. Competition among species                            

D. Availability of food resources

1
2 tháng 5 2017

Đáp án : B

Từ dòng 3 đoạn 1: Rapid ecological change may render an environment hostile to a species. For example, temperatures may change and a species may not be adapted. Food resources may be affected by environmental changes, which will then cause problems for a species requiring these resources. Other species may become better adapted to an environment, resulting in competition -> các đáp án đều được nhắc tới trừ đáp án B

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 from 28 to 34.         It is estimated that over 99 percent of all species that ever existed have become extinct. What causes extinction? When a species is no longer adapted to a changed environment, it may perish. The exact causes of a species' death vary from situation to situation. Rapid ecological change may render an environment hostile to a species. For...
Đọc tiếp

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 from 28 to 34.

        It is estimated that over 99 percent of all species that ever existed have become extinct. What causes extinction? When a species is no longer adapted to a changed environment, it may perish. The exact causes of a species' death vary from situation to situation. Rapid ecological change may render an environment hostile to a species. For example, temperatures may change and a species may not be able to adapt. Food Resources may be affected by environmental changes, which will then cause problems for a species requiring these resources. Other species may become better adapted to an environment, resulting in competition and, ultimately, in the death of a species.

        The fossil record reveals that extinction has occurred throughout the history of Earth. Recent analyses have also revealed that on some occasions many species became extinct at the same time - a mass extinction. One of the best-known examples of mass extinction occurred 65 million years ago with the demise of dinosaurs and many other forms of life. Perhaps the largest mass extinction was the one that occurred 225 million years ago. When approximately 95 percent of all species died, mass extinctions can be caused by a relatively rapid change in the environment and can be worsened by the close interrelationship of many species. If, for example, something were to happen to destroy much of the plankton in the oceans, then the oxygen content of Earth would drop, affection even organisms not living in the oceans. Such a change would probably lead to a mass extinction.

        One interesting, and controversial, finding is that extinctions during the past 250 million years have tended to be more intense every 26 million years. This periodic extinction might be due to intersection of the Earth’s orbit with a cloud of comets, but this theory is purely speculative. Some researchers have also speculated that extinction may often be random. That is, certain species may be eliminated and others may survive for no particular reason. A species’ survival may have nothing to do with its ability or inability to adapt. If so, some of evolutionary history may reflect a sequence of essentially random events.

Which of the following is NOT mentioned in paragraph 1 as resulting from rapid ecological change?

A. Temperature changes

B. Availability of food resources 

C. Introduction of new species

D. Competition among species

1
11 tháng 10 2017

Chọn C

Read the following passage and mark the letter A, B, C or D to indicate the correct answer to each of the questions from 43 to 50.     It is estimated that over 99 percent of all species that ever existed have become extinct. What causes extinction? When a species is no longer adapted to a changed environment, it may perish. The exact causes of a species' death vary from situation to situation. Rapid ecological change may render an environment hostile to a species. For example, temperatures may...
Đọc tiếp

Read the following passage and mark the letter A, B, C or D to indicate the correct answer to each of the questions from 43 to 50.

     It is estimated that over 99 percent of all species that ever existed have become extinct. What causes extinction? When a species is no longer adapted to a changed environment, it may perish. The exact causes of a species' death vary from situation to situation. Rapid ecological change may render an environment hostile to a species. For example, temperatures may change and a species may not be adapted. Food resources may be affected by environmental changes, which will then cause problems for a species requiring these resources. Other species may become better adapted to an environment, resulting in competition and, ultimately, in the death of a species.

     The fossil record reveals that extinction has occurred throughout the history of Earth. Recent analyses have also revealed that on some occasions many species became extinct at the same time - a mass extinction. One of the best-known examples of mass extinction occurred 65 million years ago with the demise of dinosaurs and many other forms of life. Perhaps the largest mass extinction was the one that occurred 225 million years ago, when approximately 95 percent of all species died. Mass extinctions can be caused by a relatively rapid change in the environment and can be worsened by the close interrelationship of many species. If, for example, something were to happen to destroy much of the plankton in the oceans, then the oxygen content of Earth would drop, even affect organisms not living in the oceans. Such a change would probably lead to a mass extinction.

     One interesting, and controversial, finding is that extinctions during the past 250 million years have tended to be more intense every 26 million years. The periodic extinction might be due to intersection of the earth's orbit with a cloud of comets, but this theory is purely speculative. Some researchers have also speculated that extinction may often be random. That is, certain species may be eliminated and others may survive for no particular reason. A species' survival may have nothing to do with its ability or inability to adapt. If so, some of revolutionary history may reflect a sequence of essentially random events.

 

Which of the following can be inferred from the theory of periodic extinction mentioned in paragraph 3?

A. many scientists could be expected to disagree with it

B. most scientists believe the theory to be accurate

C. the theory is no longer seriously considered

D. evidence to support the theory has recently been found

1
15 tháng 5 2019

Đáp án A

Dịch nghĩa: Từ học thuyết tuyệt chủng chu kì được đề cập ở đoạn 3 có thể suy ra điều gì?

A. rất nhiều nhà khoa học có thể phản đối nó.

B. hầu hết các nhà khoa học tin học thuyết này là đúng.

C. học thuyết này không còn được xem xét một cách nghiêm túc nữa.

D. bằng chứng để ủng hộ học thuyết này đã được tìm ra.

Giải thích: Thông tin nằm ở “The periodic extinction might be due to intersection of the earth’s orbit with a cloud of comets, but this theory is purely speculative”. Vì nó hoàn toàn là suy đoán nên ta có thể suy đoán rằng nó bị nhiều nhà khoa học khác phản đối.

Read the following passage and mark the letter A, B, C or D to indicate the correct answer to each of the questions from 43 to 50. It is estimated that over 99 percent of all species that ever existed have become extinct. What causes extinction? When a species is no longer adapted to a changed environment, it may perish. The exact causes of a species' death vary from situation to situation. Rapid ecological change may render an environment hostile to a species. For example, temperatures may...
Đọc tiếp

Read the following passage and mark the letter A, B, C or D to indicate the correct answer to each of the questions from 43 to 50.

It is estimated that over 99 percent of all species that ever existed have become extinct. What causes extinction? When a species is no longer adapted to a changed environment, it may perish. The exact causes of a species' death vary from situation to situation. Rapid ecological change may render an environment hostile to a species. For example, temperatures may change and a species may not be adapted. Food resources may be affected by environmental changes, which will then cause problems for a species requiring these resources. Other species may become better adapted to an environment, resulting in competition and, ultimately, in the death of a species.

The fossil record reveals that extinction has occurred throughout the history of Earth. Recent analyses have also revealed that on some occasions many species became extinct at the same time - a mass extinction. One of the best-known examples of mass extinction occurred 65 million years ago with the demise of dinosaurs and many other forms of life. Perhaps the largest mass extinction was the one that occurred 225 million years ago, when approximately 95 percent of all species died. Mass extinctions can be caused by a relatively rapid change in the environment and can be worsened by the close interrelationship of many species. If, for example, something were to happen to destroy much of the plankton in the oceans, then the oxygen content of Earth would drop, even affect organisms not living in the oceans. Such a change would probably lead to a mass extinction.

One interesting, and controversial, finding is that extinctions during the past 250 million years have tended to be more intense every 26 million years. The periodic extinction might be due to intersection of the earth's orbit with a cloud of comets, but this theory is purely speculative. Some researchers have also speculated that extinction may often be random. That is, certain species may be eliminated and others may survive for no particular reason. A species' survival may have nothing to do with its ability or inability to adapt. If so, some of revolutionary history may reflect a sequence of essentially random events.

Question50: In paragraph 3, the author makes which of the following statements about a species' survival?

A. it may depend on chance events.

B. it does not vary greatly from species to species.

C. it reflects the interrelationship of many species.

D. it is associated with astronomical conditions.

1
8 tháng 2 2018

Đáp án A

Dịch nghĩa: Ở đoạn 3, tác giả nói gì về sự tồn tại của một loài?

A. Nó có thể phụ thuộc vào những việc xảy ra tình cờ.

B. Nó không khác nhau nhiều giữa các loài.

C. Nó phản ánh mối liên hệ giữa các loài.

D. Nó liên quan đến điều kiện thiên văn học.

Read the following passage and mark the letter A, B, C or D to indicate the correct answer to each of the questions from 43 to 50.     It is estimated that over 99 percent of all species that ever existed have become extinct. What causes extinction? When a species is no longer adapted to a changed environment, it may perish. The exact causes of a species' death vary from situation to situation. Rapid ecological change may render an environment hostile to a species. For example, temperatures may...
Đọc tiếp

Read the following passage and mark the letter A, B, C or D to indicate the correct answer to each of the questions from 43 to 50.

     It is estimated that over 99 percent of all species that ever existed have become extinct. What causes extinction? When a species is no longer adapted to a changed environment, it may perish. The exact causes of a species' death vary from situation to situation. Rapid ecological change may render an environment hostile to a species. For example, temperatures may change and a species may not be adapted. Food resources may be affected by environmental changes, which will then cause problems for a species requiring these resources. Other species may become better adapted to an environment, resulting in competition and, ultimately, in the death of a species.

     The fossil record reveals that extinction has occurred throughout the history of Earth. Recent analyses have also revealed that on some occasions many species became extinct at the same time - a mass extinction. One of the best-known examples of mass extinction occurred 65 million years ago with the demise of dinosaurs and many other forms of life. Perhaps the largest mass extinction was the one that occurred 225 million years ago, when approximately 95 percent of all species died. Mass extinctions can be caused by a relatively rapid change in the environment and can be worsened by the close interrelationship of many species. If, for example, something were to happen to destroy much of the plankton in the oceans, then the oxygen content of Earth would drop, even affect organisms not living in the oceans. Such a change would probably lead to a mass extinction.

     One interesting, and controversial, finding is that extinctions during the past 250 million years have tended to be more intense every 26 million years. The periodic extinction might be due to intersection of the earth's orbit with a cloud of comets, but this theory is purely speculative. Some researchers have also speculated that extinction may often be random. That is, certain species may be eliminated and others may survive for no particular reason. A species' survival may have nothing to do with its ability or inability to adapt. If so, some of revolutionary history may reflect a sequence of essentially random events.

 

In paragraph 3, the author makes which of the following statements about a species' survival?

A. it may depend on chance events

B. it does not vary greatly from species to species

C. it reflects the interrelationship of many species

D. it is associated with astronomical conditions

1
18 tháng 2 2017

Đáp án A

Dịch nghĩa: Ở đoạn 3, tác giả nói gì về sự tồn tại của một loài?

A. Nó có thể phụ thuộc vào những việc xảy ra tình cờ.

B. Nó không khác nhau nhiều giữa các loài.

C. Nó phản ánh mối liên hệ giữa các loài.

D. Nó liên quan đến điều kiện thiên văn học.

Bài dịch

Người ta ước tính rằng hơn 99 phần trăm tất cả các loài từng tồn tại đã bị tuyệt chủng. Điều gì gây ra sự tuyệt chủng? Khi một loài không còn thích nghi với môi trường đã thay đổi, nó có thể biến mất. Các nguyên nhân chính dẫn đến một loài chết đi khác nhau đối với các trường hợp khác nhau. Sự thay đổi hệ sinh thái quá nhanh có thể khiến môi trường sống trở nên khó khăn với các loài đó. Ví dụ, nhiệt độ có thể thay đổi mà một loài không thể thích nghi. Nguồn thức ăn có thể bị ảnh hưởng bởi những thay đổi của môi trường, sau đó sẽ tiếp tục gây ra những vấn đề khác cho loài mà cần sử dụng nguồn thức ăn này. Các loài khác có thể thích nghi tốt hơn với môi trường, dẫn đến sự cạnh tranh và cuối cùng, là cái chết của một loài nào đó.

Các mẫu hóa thạch cho thấy rằng sự tuyệt chủng đã xảy ra trong suốt lịch sử của trái đất. Phân tích gần đây cũng tiết lộ rằng trong một số trường hợp nhiều loài đã tuyệt chủng cùng lúc - tuyệt chủng hàng loạt. Một trong những ví dụ nổi bật nhất của tuyệt chủng hàng loạt xảy ra vào 65 triệu năm trước đây với sự sụp đổ của khủng long và nhiều sinh vật sống khác. Có lẽ lần tuyệt chủng hàng loạt lớn nhất xảy ra vào 225 triệu năm trước đây, khi khoảng 95 phần trăm số loài đã chết. Tuyệt chủng hàng loạt có thể bị gây ra bởi sự thay đổi tương đối nhanh chóng của môi trường và có thể trở nên tồi tệ hơn bởi các mối liên hệ mật thiết giữa các loài. Ví dụ, nếu một điều gì đó đã xảy ra và tiêu diệt nhiều sinh vật phù du trong các đại dương, sau đó hàm lượng oxy của trái đất sẽ giảm, thậm chí ảnh hưởng đến các sinh vật không sống trong đại dương. Một sự thay đổi như vậy có thế sẽ dẫn đến sự tuyệt chủng hàng loạt.

Một khám phá thú vị, và cũng gây nhiều tranh cãi, đó là sự tuyệt chủng trong suốt 250 triệu năm qua đã có xu hướng tăng mạnh mẽ hơn sau mỗi 26 triệu năm. Sự tuyệt chủng có chu kỳ này có thể là do giao điểm của quỹ đạo trái đất với một đám mây sao chổi, nhưng thuyết này hoàn toàn chỉ là suy đoán. Một số nhà nghiên cứu cũng đã cho rằng sự tuyệt chủng thường là ngẫu nhiên. Nghĩa là một số loài bị loại bỏ và những loài khác có thể tiếp tục tồn tại mà không có lý do cụ thể nào. Sự tồn tại của một loài có thể không liên quan gì đến khả năng thích nghi hay không thích nghi của chúng. Nếu vậy, một vài sự tiến hóa lịch sử có thể phản ánh một chuỗi các sự kiện ngẫu nhiên quan trọng.

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 It is estimated that over 99 percent of all species that have existed have become extinct. What causes extinction? When a species is no longer adapted to a changed environment, it may perish. The exact causes of a species' death vary from situation to situation. Rapid ecological change may render an environment hostile to a species. For example, temperatures...
Đọc tiếp

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

It is estimated that over 99 percent of all species that have existed have become extinct. What causes extinction? When a species is no longer adapted to a changed environment, it may perish. The exact causes of a species' death vary from situation to situation. Rapid ecological change may render an environment hostile to a species. For example, temperatures may change and a species may not be able to adapt. Food resources may be affected by environmental changes, which will then cause problems for a species requiring these resources. Other species may become better adapted to an environment, resulting in competition and, ultimately, in the death of a species.

The fossil record reveals that extinction has occurred throughout the history of Earth. Recent analyses have also revealed that on some occasions, many species became extinct at the same time- a mass extinction. One of the best-known examples of mass extinction occurred 65 mmion years ago with the demise of dinosaurs and many other forms of life. Perhaps the largest mass extinction was the one that occurred 225 million years ago, when approximately 95 percent of all species died. Mass extinction can be caused by a relatively rapid change in the environment and can be worsened by the close interrelationship of many species. If, for example, something were to happen to destroy much of the plankton in the oceans, then the oxygen content of Earth would drop, affecting even organisms not living in the oceans. Such a change would probably lead to a mass extinction.

One interesting, and controversial, finding is that extinctions during the past 250 million years have tended to be more intensive every 26 million years. This periodic extinction might be due to intersection of the Earth's orbit with a cloud of comets, but this theory is purely speculative. Some researchers have also speculated that extinction may often be random. That is, certain species may be eliminated and others may survive for no particular reason. A species' survival may have nothing to do with its ability or inability to adapt. If so, some of evolutionary history may reflect a sequence of essentially random events. 

Which of the following is NOT mentioned in paragraph 1 as resulting from rapid ecological change?

A. Availability of food sources 

B. Temperature changes 

C. Introduction of new species 

D. Competition among species 

1
17 tháng 2 2017

Kiến thức: Đọc hiểu

Giải thích:

Điều nào sau đây KHÔNG được đề cập trong đoạn 1 do kết quả của sự thay đổi sinh thái nhanh chóng?

A. Nguồn thức ăn sẵn có                B. Thay đổi nhiệt độ

C. Giới thiệu loài mới                     D. Cạnh tranh giữa các loài

Thông tin: For example, temperatures may change and a species may not be adapt. Food resources may be affected by environmental changes, which will then cause problems for a species requiring these resources. Other species may become better adapted to an environment, resulting in competition and, ….

Tạm dịch: Ví dụ như, nhiệt độ thay đổi và sinh vật không thích ứng được. Nguồn thức ăn có thể bị ảnh hưởng bởi sự thay đổi môi trường, điều đó sẽ gây ra những vấn đề cho nhu cầu thức ăn của loài. Những loài khác có thể thích ứng tốt hơn,với môi trường, dẫn đến sự cạnh tranh …

Chọn C 

Read the following passage and mark the letter A, B, C or D to indicate the correct answer to each of the questions from 43 to 50. It is estimated that over 99 percent of all species that ever existed have become extinct. What causes extinction? When a species is no longer adapted to a changed environment, it may perish. The exact causes of a species' death vary from situation to situation. Rapid ecological change may render an environment hostile to a species. For example, temperatures may...
Đọc tiếp

Read the following passage and mark the letter A, B, C or D to indicate the correct answer to each of the questions from 43 to 50.

It is estimated that over 99 percent of all species that ever existed have become extinct. What causes extinction? When a species is no longer adapted to a changed environment, it may perish. The exact causes of a species' death vary from situation to situation. Rapid ecological change may render an environment hostile to a species. For example, temperatures may change and a species may not be adapted. Food resources may be affected by environmental changes, which will then cause problems for a species requiring these resources. Other species may become better adapted to an environment, resulting in competition and, ultimately, in the death of a species.

The fossil record reveals that extinction has occurred throughout the history of Earth. Recent analyses have also revealed that on some occasions many species became extinct at the same time - a mass extinction. One of the best-known examples of mass extinction occurred 65 million years ago with the demise of dinosaurs and many other forms of life. Perhaps the largest mass extinction was the one that occurred 225 million years ago, when approximately 95 percent of all species died. Mass extinctions can be caused by a relatively rapid change in the environment and can be worsened by the close interrelationship of many species. If, for example, something were to happen to destroy much of the plankton in the oceans, then the oxygen content of Earth would drop, even affect organisms not living in the oceans. Such a change would probably lead to a mass extinction.

One interesting, and controversial, finding is that extinctions during the past 250 million years have tended to be more intense every 26 million years. The periodic extinction might be due to intersection of the earth's orbit with a cloud of comets, but this theory is purely speculative. Some researchers have also speculated that extinction may often be random. That is, certain species may be eliminated and others may survive for no particular reason. A species' survival may have nothing to do with its ability or inability to adapt. If so, some of revolutionary history may reflect a sequence of essentially random events.

Question 45: What does the author say in paragraph 1 regarding most species in Earth's history?

A. they have remained basically unchanged from their original forms.

B. they are no longer in existence.

C. they have been able to adapt to ecological changes.

D. they have caused rapid change in the environment.

1
1 tháng 5 2019

Đáp án B

Dịch nghĩa: Tác giả nói gì về phần lớn các loài động vật trong lịch sử trái đất ở đoạn l?

A. Chúng gần như không thay đổi gì so với thời xưa.

B. Chúng không còn tồn tại.

C. Chúng đã thích nghi với sự thay đổi sinh thái.

D. Chúng gây ra những thay đổi nhanh chóng đến môi trường.

Giải thích: Thông tin nằm ở “It is estimated that over 99 percent of all species that ever existed have become extinct”.

Read the following passage and mark the letter A, B, C or D to indicate the correct answer to each of the questions from 43 to 50.     It is estimated that over 99 percent of all species that ever existed have become extinct. What causes extinction? When a species is no longer adapted to a changed environment, it may perish. The exact causes of a species' death vary from situation to situation. Rapid ecological change may render an environment hostile to a species. For example, temperatures may...
Đọc tiếp

Read the following passage and mark the letter A, B, C or D to indicate the correct answer to each of the questions from 43 to 50.

     It is estimated that over 99 percent of all species that ever existed have become extinct. What causes extinction? When a species is no longer adapted to a changed environment, it may perish. The exact causes of a species' death vary from situation to situation. Rapid ecological change may render an environment hostile to a species. For example, temperatures may change and a species may not be adapted. Food resources may be affected by environmental changes, which will then cause problems for a species requiring these resources. Other species may become better adapted to an environment, resulting in competition and, ultimately, in the death of a species.

     The fossil record reveals that extinction has occurred throughout the history of Earth. Recent analyses have also revealed that on some occasions many species became extinct at the same time - a mass extinction. One of the best-known examples of mass extinction occurred 65 million years ago with the demise of dinosaurs and many other forms of life. Perhaps the largest mass extinction was the one that occurred 225 million years ago, when approximately 95 percent of all species died. Mass extinctions can be caused by a relatively rapid change in the environment and can be worsened by the close interrelationship of many species. If, for example, something were to happen to destroy much of the plankton in the oceans, then the oxygen content of Earth would drop, even affect organisms not living in the oceans. Such a change would probably lead to a mass extinction.

     One interesting, and controversial, finding is that extinctions during the past 250 million years have tended to be more intense every 26 million years. The periodic extinction might be due to intersection of the earth's orbit with a cloud of comets, but this theory is purely speculative. Some researchers have also speculated that extinction may often be random. That is, certain species may be eliminated and others may survive for no particular reason. A species' survival may have nothing to do with its ability or inability to adapt. If so, some of revolutionary history may reflect a sequence of essentially random events.

 

What does the author say in paragraph 1 regarding most species in Earth's history?

A. they have remained basically unchanged from their original forms

B. they are no longer in existence

C. they have been able to adapt to ecological changes

D. they have caused rapid change in the environment

1
15 tháng 5 2019

Đáp án B

Dịch nghĩa: Tác giả nói gì về phần lớn các loài động vật trong lịch sử trái đất ở đoạn l?

A. Chúng gần như không thay đổi gì so với thời xưa.

B. Chúng không còn tồn tại.

C. Chúng đã thích nghi với sự thay đổi sinh thái.

D. Chúng gây ra những thay đổi nhanh chóng đến môi trường.

Giải thích: Thông tin nằm ở “It is estimated that over 99 percent of all species that ever existed have become extinct”.

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.It is estimated that over 99 percent of all species that ever existed have become extinct. What causes extinction? When a species is no longer adapted to a changed environment, it may perish. The exact causes of a species’ death vary from situation to situation. Rapid ecological change may render an environment hostile to a species. For example,...
Đọc tiếp

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.

It is estimated that over 99 percent of all species that ever existed have become extinct. What causes extinction? When a species is no longer adapted to a changed environment, it may perish. The exact causes of a species’ death vary from situation to situation. Rapid ecological change may render an environment hostile to a species. For example, temperatures may change and a species may not be adapted. Food resources may be affected by environmental changes, which will then cause problems for a species requiring these resources. Other species may become better adapted to an environment, resulting in competition and, ultimately, in the death of a species.

The fossil record reveals that extinction has occurred throughout the history of  Earth. Recent analyses have also revealed that on some occasions many species became extinct at the same time - a mass extinction. One of the best-known examples of mass extinction occurred 65 million years ago with the demise of dinosaurs and many other forms of life. Perhaps the largest mass extinction was the one that occurred 225 million years ago, when approximately 95 percent of all species died. Mass extinctions can be caused by a relatively rapid change in the environment and can be worsened by the close interrelationship of many species. If, for example, something were to happen to destroy much of the plankton in the oceans, then the oxygen content of Earth would drop, even affect organisms not living in the oceans. Such a change would probably lead to a mass extinction.

One interesting, and controversial, finding is that extinctions during the past 250 million years have tended to be more intense every 26 million years. The periodic extinction might be due to intersection of the earth’s orbit with a cloud of comets, but this theory is purely speculative. Some researchers have also speculated that extinction may often be random. That is, certain species may be eliminated and others may survive for no particular reason. A species’ survival may have nothing to do with its ability or inability to adapt. If so, some of revolutionary history may reflect a sequence of essentially random events.

Which of the following can be inferred from the theory of periodic extinction mentioned in paragraph 3?

A. The theory is no longer seriously considered. 

B. evidence to support the theory has recently been found.

C. Most scientists believe the theory to be accurate.

D. Many scientists could be expected to disagree with it.

1
23 tháng 2 2019

Đáp án : D

Đầu đoạn cuối: One interesting, and controversial finding is that extinctions during the past 250 million years have tended to be more intense every 26 million years. The periodic extinction… is purely speculative -> phát hiện gây tranh gãi rằng sự tuyệt chủng 250 triệu năm qua cứ 26 triệu năm một lần sẽ gay gắt hơn. Thuyết tuyệt chủng theo giai đoạn này chỉ là suy đoán ---> nhiều nhà khoa học không đồng ý