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25 tháng 7 2017

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Our primary method of research has been conducting short interviews with a large number of people.We decided that,unlike other almost every other study-based project we heard about,this one would make no categorical distinction between men and(1)..women.The two main groups,rather,would be adults and children,the idea for this obviously(2)coming...from the fact that 10-years-old cousin and I had(3)nearly...indentical experiences.It should come as no surprise that,since they were generally more(4). unwilling.than children to be interviewed by us.Surprisingly though,many of these adults were quiet willing to give us(5).permission..to interview their own children,who were generally much more(6). enthusiastic​.about the chance to talk about their dreams.Because of their helpfulness,we've already had(7).264..children subjects alone,and well over 350 total repondents.

25 tháng 7 2017

Our primary method of research has been conducting short interviews with a large number of people.We decided that,unlike other almost every other study-based project we heard about,this one would make no categorical distinction between men and(1) women ...The two main groups,rather,would be adults and children,the idea for this obviously(2).coming..from the fact that 10-years-old cousin and I had(3)nearly...indentical experiences.It should come as no surprise that,since they were generally more(4) unwilling ...than children to be interviewed by us.Surprisingly though,many of these adults were quiet willing to give us(5).. permission .to interview their own children,who were generally much more(6)..enthusiatic.about the chance to talk about their dreams.Because of their helpfulness,we've already had(7)..264 .children subjects alone,and well over 350 total repondents.

Mk ko chắc

Read the following passage on transport, and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 38 to 42. (1) The protozoans, minute, aquatic creatures each of which consists of a single cell of protoplasm, constitute a classification of the most primitive forms of animal life. They are fantastically diverse, but three major groups may be identified on the basis of their motility. The Mastigophora have one or more long tails, which...
Đọc tiếp

Read the following passage on transport, and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 38 to 42.

(1) The protozoans, minute, aquatic creatures each of which consists of a single cell of protoplasm, constitute a classification of the most primitive forms of animal life. They are fantastically diverse, but three major groups may be identified on the basis of their motility. The Mastigophora have one or more long tails, which they use to project themselves forward. The Ciliata, which use the same basic means for locomotion as the Mastigophora, have a larger number of short tails. The Sarcodina, which include amoebae, float or row themselves about on their crusted bodies.

(2) In addition to their form of movement, several other features discriminate among the three groups of protozoans. For example, at least two nuclei per cell have been identified in the Ciliata, usually a large nucleus that regulates growth but decomposes during reproduction, and a smaller one that contains the genetic code necessary to generate the large nucleus.

(3) Protozoans are considered animals because, unlike pigmented plants to which some protozoans are otherwise almost identical, they do not live on simple organic compounds. Their cell demonstrates all of the major characteristics of the cells of higher animals.

(4) Many species of protozoans collect into colonies, physically connected to each other and responding uniformly to outside stimulae. Current research into this phenomenon, along with investigations carried out with advanced microscopes may necessitate a redefinition of what constitutes protozoans, even calling into question the basic premise that they have only one cell. Nevertheless, with the current data available, almost 40,000 species of protozoans have been identified. No doubt, as the technology improves our methods of observation, better models of classification will be proposed.  

What is protoplasm?

A. A class of protozoan 

B. The substance that forms the cell of a protozoan 

C. A primitive animal similar to a protozoan 

D. An animal that developed from a protozoan

1
14 tháng 10 2019

Đáp án B

(1) The protozoans, minute, aquatic creatures each of which consists of a single cell of protoplasm

Read the following passage on transport, and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 43 to 50. (1) The protozoans, minute, aquatic creatures each of which consists of a single cell of protoplasm, constitute a classification of the most primitive forms of animal life. They are fantastically diverse, but three major groups may be identified on the basis of their motility. The Mastigophora have one or more long tails, which...
Đọc tiếp

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

(1) The protozoans, minute, aquatic creatures each of which consists of a single cell of protoplasm, constitute a classification of the most primitive forms of animal life. They are fantastically diverse, but three major groups may be identified on the basis of their motility. The Mastigophora have one or more long tails, which they use to project themselves forward. The Ciliata, which use the same basic means for locomotion as the Mastigophora, have a larger number of short tails. The Sarcodina, which include amoebae, float or row themselves about on their crusted bodies.

(2) In addition to their form of movement, several other features discriminate among the three groups of protozoans. For example, at least two nuclei per cell have been identified in the Ciliata, usually a large nucleus that regulates growth but decomposes during reproduction, and a smaller one that contains the genetic code necessary to generate the large nucleus.

(3) Protozoans are considered animals because, unlike pigmented plants to which some protozoans are otherwise almost identical, they do not live on simple organic compounds. Their cell demonstrates all of the major characteristics of the cells of higher animals.

(4) Many species of protozoans collect into colonies, physically connected to each other and responding uniformly to outside stimulae. Current research into this phenomenon, along with investigations carried out with advanced microscopes may necessitate a redefinition of what constitutes protozoans, even calling into question the basic premise that they have only one cell. Nevertheless, with the current data available, almost 40,000 species of protozoans have been identified. No doubt, as the technology improves our methods of observation, better models of classification will be proposed.

What is protoplasm?

A. A class of protozoan

B. The substance that forms the cell of a protozoan

C. A primitive animal similar to a protozoan

D. An animal that developed from a protozoan

1
16 tháng 12 2019

Đáp án B
(1) The protozoans, minute, aquatic creatures each of which consists of a single cell of protoplasm

Read the following passage on transport, and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 1 to 7. (1) The protozoans, minute, aquatic creatures each of which consists of a single cell of protoplasm, constitute a classification of the most primitive forms of animal life. They are fantastically diverse, but three major groups may be identified on the basis of their motility. The Mastigophora have one or more long tails, which they...
Đọc tiếp

Read the following passage on transport, and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 1 to 7.

(1) The protozoans, minute, aquatic creatures each of which consists of a single cell of protoplasm, constitute a classification of the most primitive forms of animal life. They are fantastically diverse, but three major groups may be identified on the basis of their motility. The Mastigophora have one or more long tails, which they use to project themselves forward. The Ciliata, which use the same basic means for locomotion as the Mastigophora, have a larger number of short tails. The Sarcodina, which include amoebae, float or row themselves about on their crusted bodies.

(2) In addition to their form of movement, several other features discriminate among the three groups of protozoans. For example, at least two nuclei per cell have been identified in the Ciliata, usually a large nucleus that regulates growth but decomposes during reproduction, and a smaller one that contains the genetic code necessary to generate the large nucleus.

(3) Protozoans are considered animals because, unlike pigmented plants to which some protozoans are otherwise almost identical, they do not live on simple organic compounds. Their cell demonstrates all of the major characteristics of the cells of higher animals.

(4) Many species of protozoans collect into colonies, physically connected to each other and responding uniformly to outside stimulae. Current research into this phenomenon, along with investigations carried out with advanced microscopes may necessitate a redefinition of what constitutes protozoans, even calling into question the basic premise that they have only one cell. Nevertheless, with the current data available, almost 40,000 species of protozoans have been identified. No doubt, as the technology improves our methods of observation, better models of classification will be proposed.

What is protoplasm?

A. A class of protozoan

B. The substance that forms the cell of a protozoan

C. A primitive animal similar to a protozoan

D. An animal that developed from a protozoan

1
2 tháng 10 2018

Đáp án B

(1) The protozoans, minute, aquatic creatures each of which consists of a single cell of protoplasm

Read the following passage on transport, and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 43 to 50. (1) The protozoans, minute, aquatic creatures each of which consists of a single cell of protoplasm, constitute a classification of the most primitive forms of animal life. They are fantastically diverse, but three major groups may be identified on the basis of their motility. The Mastigophora have one or more long tails, which...
Đọc tiếp

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

(1) The protozoans, minute, aquatic creatures each of which consists of a single cell of protoplasm, constitute a classification of the most primitive forms of animal life. They are fantastically diverse, but three major groups may be identified on the basis of their motility. The Mastigophora have one or more long tails, which they use to project themselves forward. The Ciliata, which use the same basic means for locomotion as the Mastigophora, have a larger number of short tails. The Sarcodina, which include amoebae, float or row themselves about on their crusted bodies.

(2) In addition to their form of movement, several other features discriminate among the three groups of protozoans. For example, at least two nuclei per cell have been identified in the Ciliata, usually a large nucleus that regulates growth but decomposes during reproduction, and a smaller one that contains the genetic code necessary to generate the large nucleus.

(3) Protozoans are considered animals because, unlike pigmented plants to which some protozoans are otherwise almost identical, they do not live on simple organic compounds. Their cell demonstrates all of the major characteristics of the cells of higher animals.

(4) Many species of protozoans collect into colonies, physically connected to each other and responding uniformly to outside stimulate. Current research into this phenomenon, along with investigations carried out with advanced microscopes may necessitate a redefinition of what constitutes protozoans, even calling into question the basic premise that they have only one cell. Nevertheless, with the current data available, almost 40,000 species of protozoans have been identified. No doubt, as the technology improves our methods of observation, better models of classification will be proposed.

What is protoplasm?

(A) A class of protozoan

(B) The substance that forms the cell of a protozoan

(C) A primitive animal similar to a protozoan

(D) An animal that developed from a protozoan

1
26 tháng 6 2019

Đáp án B

(1) The protozoans, minute, aquatic creatures each of which consists of a single cell of protoplasm

Dịch bài

(1) Sinh vật đơn bào, loài sinh vật nhỏ, sống trong nước, với mỗi cá thểbao gồm một tế bào duy nhất gồm chất nguyên sinh, tạo thành một nhóm các loài sinh vật nguyên thủy nhất trong thế giới động vật. Chúng rất đa dạng, nhưng nhìn chung có thể chia thành 3 nhóm dựa trên cơ chế di chuyển. Nhóm Mastigophora có một hoặc nhiều đuôi dài, giúp đẩy cơ thể về phía trước. Nhóm Ciliata, có cùng cơ chế vận động như Mastigophora, nhưng nhiều đuôi ngắn hơn. Nhóm Sarcodina, bao gồm trùng amip, trôi nổi hoặc di chuyển trong nước bằng chính cơ thể có lớp bảo vệ bên ngoài của mình

(2) Ngoài hình thức di chuyển, có một số các đặc điểm khác giúp phân biệt 3 nhóm sinh vật đơn bào. Ví dụ, nhóm Ciliata có ít nhất 2 nhân mỗi tế bào, thường một nhân lớn quy định đặc điểm tăng trưởng nhưng phân hủy trong quá trình sinh sản, và một nhân nhỏ hơn có chứa mã di truyền cần thiết để tạo ra nhân lớn.

(3) Sinh vật đơn bào được coi là động vật bởi vì, không giống thực vật có sắc tố mà một số loài sinh vật đơn bào giống y hệt, chúng không sống bằng các hợp chất hữu cơ đơn giản. Tế bào của chúng thể hiện tất cả các đặc điểm chính của tế bào ở động vật bậc cao.

(4) Nhiều loài sinh vật đơn bào tập hợp các cá thể lại với nhau, gọi là các “tập đoàn trùng roi” với mối liên kết chặt chẽ của các bộ phận và phản ứng đồng nhất với kích thích từ bên ngoài. Những nghiên cứu gần đây về hiện tượng này, cùng với những quan sát bằng kính hiển vi cao cấp có lẽ sẽ buộc chúng ta phải định nghĩa lại thế nào là sinh vật đơn bảo, thậm chí phải xem lại định nghĩa cơ bản nhất rằng chúng có thực sự có 1 tế bào hay không. Dù vậy, với các dữ liệu hiện có, các nhà khoa học đã xác định được khoảng 40,000 loại sinh vật đơn bào. Chắc chắn, khi các phương thức quan sát của chúng ta được cải thiện nhờ công nghệ, sẽ có thêm nhiều các mô hình phân loại ưu việt hơn được đưa ra.

Read the following passage on transport, and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 43 to 50. (1) The protozoans, minute, aquatic creatures each of which consists of a single cell of protoplasm, constitute a classification of the most primitive forms of animal life. They are fantastically diverse, but three major groups may be identified on the basis of their motility. The Mastigophora have one or more long tails, which...
Đọc tiếp

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

(1) The protozoans, minute, aquatic creatures each of which consists of a single cell of protoplasm, constitute a classification of the most primitive forms of animal life. They are fantastically diverse, but three major groups may be identified on the basis of their motility. The Mastigophora have one or more long tails, which they use to project themselves forward. The Ciliata, which use the same basic means for locomotion as the Mastigophora, have a larger number of short tails. The Sarcodina, which include amoebae, float or row themselves about on their crusted bodies.

(2) In addition to their form of movement, several other features discriminate among the three groups of protozoans. For example, at least two nuclei per cell have been identified in the Ciliata, usually a large nucleus that regulates growth but decomposes during reproduction, and a smaller one that contains the genetic code necessary to generate the large nucleus.

(3) Protozoans are considered animals because, unlike pigmented plants to which some protozoans are otherwise almost identical, they do not live on simple organic compounds. Their cell demonstrates all of the major characteristics of the cells of higher animals.

(4) Many species of protozoans collect into colonies, physically connected to each other and responding uniformly to outside stimulae. Current research into this phenomenon, along with investigations carried out with advanced microscopes may necessitate a redefinition of what constitutes protozoans, even calling into question the basic premise that they have only one cell. Nevertheless, with the current data available, almost 40,000 species of protozoans have been identified. No doubt, as the technology improves our methods of observation, better models of classification will be proposed.

What is the purpose of the large nucleus in the Ciliata?

A. It generates the other nucleus.

B. It contains the genetic code for the small nucleus.

C. It regulates growth.

D. It reproduces itself.

1
31 tháng 7 2019

Đáp án C
(1) usually a large nucleus that regulates growth but decomposes during reproduction

Read the following passage on transport, and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 43 to 50. (1) The protozoans, minute, aquatic creatures each of which consists of a single cell of protoplasm, constitute a classification of the most primitive forms of animal life. They are fantastically diverse, but three major groups may be identified on the basis of their motility. The Mastigophora have one or more long tails, which...
Đọc tiếp

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

(1) The protozoans, minute, aquatic creatures each of which consists of a single cell of protoplasm, constitute a classification of the most primitive forms of animal life. They are fantastically diverse, but three major groups may be identified on the basis of their motility. The Mastigophora have one or more long tails, which they use to project themselves forward. The Ciliata, which use the same basic means for locomotion as the Mastigophora, have a larger number of short tails. The Sarcodina, which include amoebae, float or row themselves about on their crusted bodies.

(2) In addition to their form of movement, several other features discriminate among the three groups of protozoans. For example, at least two nuclei per cell have been identified in the Ciliata, usually a large nucleus that regulates growth but decomposes during reproduction, and a smaller one that contains the genetic code necessary to generate the large nucleus.

(3) Protozoans are considered animals because, unlike pigmented plants to which some protozoans are otherwise almost identical, they do not live on simple organic compounds. Their cell demonstrates all of the major characteristics of the cells of higher animals.

(4) Many species of protozoans collect into colonies, physically connected to each other and responding uniformly to outside stimulate. Current research into this phenomenon, along with investigations carried out with advanced microscopes may necessitate a redefinition of what constitutes protozoans, even calling into question the basic premise that they have only one cell. Nevertheless, with the current data available, almost 40,000 species of protozoans have been identified. No doubt, as the technology improves our methods of observation, better models of classification will be proposed.

What is the purpose of the large nucleus in the Ciliata?

(A) It generates the other nucleus.

(B) It contains the genetic code for the small nucleus.

(C) It regulates growth.

(D) It reproduces itself.

1
21 tháng 4 2017

Đáp án C

(1) usually a large nucleus that regulates growth but decomposes during reproduction

Dịch bài

(1) Sinh vật đơn bào, loài sinh vật nhỏ, sống trong nước, với mỗi cá thểbao gồm một tế bào duy nhất gồm chất nguyên sinh, tạo thành một nhóm các loài sinh vật nguyên thủy nhất trong thế giới động vật. Chúng rất đa dạng, nhưng nhìn chung có thể chia thành 3 nhóm dựa trên cơ chế di chuyển. Nhóm Mastigophora có một hoặc nhiều đuôi dài, giúp đẩy cơ thể về phía trước. Nhóm Ciliata, có cùng cơ chế vận động như Mastigophora, nhưng nhiều đuôi ngắn hơn. Nhóm Sarcodina, bao gồm trùng amip, trôi nổi hoặc di chuyển trong nước bằng chính cơ thể có lớp bảo vệ bên ngoài của mình

(2) Ngoài hình thức di chuyển, có một số các đặc điểm khác giúp phân biệt 3 nhóm sinh vật đơn bào. Ví dụ, nhóm Ciliata có ít nhất 2 nhân mỗi tế bào, thường một nhân lớn quy định đặc điểm tăng trưởng nhưng phân hủy trong quá trình sinh sản, và một nhân nhỏ hơn có chứa mã di truyền cần thiết để tạo ra nhân lớn.

(3) Sinh vật đơn bào được coi là động vật bởi vì, không giống thực vật có sắc tố mà một số loài sinh vật đơn bào giống y hệt, chúng không sống bằng các hợp chất hữu cơ đơn giản. Tế bào của chúng thể hiện tất cả các đặc điểm chính của tế bào ở động vật bậc cao.

(4) Nhiều loài sinh vật đơn bào tập hợp các cá thể lại với nhau, gọi là các “tập đoàn trùng roi” với mối liên kết chặt chẽ của các bộ phận và phản ứng đồng nhất với kích thích từ bên ngoài. Những nghiên cứu gần đây về hiện tượng này, cùng với những quan sát bằng kính hiển vi cao cấp có lẽ sẽ buộc chúng ta phải định nghĩa lại thế nào là sinh vật đơn bảo, thậm chí phải xem lại định nghĩa cơ bản nhất rằng chúng có thực sự có 1 tế bào hay không. Dù vậy, với các dữ liệu hiện có, các nhà khoa học đã xác định được khoảng 40,000 loại sinh vật đơn bào. Chắc chắn, khi các phương thức quan sát của chúng ta được cải thiện nhờ công nghệ, sẽ có thêm nhiều các mô hình phân loại ưu việt hơn được đưa ra.

Read the following passage on transport, and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 1 to 7. (1) The protozoans, minute, aquatic creatures each of which consists of a single cell of protoplasm, constitute a classification of the most primitive forms of animal life. They are fantastically diverse, but three major groups may be identified on the basis of their motility. The Mastigophora have one or more long tails, which they...
Đọc tiếp

Read the following passage on transport, and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 1 to 7.

(1) The protozoans, minute, aquatic creatures each of which consists of a single cell of protoplasm, constitute a classification of the most primitive forms of animal life. They are fantastically diverse, but three major groups may be identified on the basis of their motility. The Mastigophora have one or more long tails, which they use to project themselves forward. The Ciliata, which use the same basic means for locomotion as the Mastigophora, have a larger number of short tails. The Sarcodina, which include amoebae, float or row themselves about on their crusted bodies.

(2) In addition to their form of movement, several other features discriminate among the three groups of protozoans. For example, at least two nuclei per cell have been identified in the Ciliata, usually a large nucleus that regulates growth but decomposes during reproduction, and a smaller one that contains the genetic code necessary to generate the large nucleus.

(3) Protozoans are considered animals because, unlike pigmented plants to which some protozoans are otherwise almost identical, they do not live on simple organic compounds. Their cell demonstrates all of the major characteristics of the cells of higher animals.

(4) Many species of protozoans collect into colonies, physically connected to each other and responding uniformly to outside stimulae. Current research into this phenomenon, along with investigations carried out with advanced microscopes may necessitate a redefinition of what constitutes protozoans, even calling into question the basic premise that they have only one cell. Nevertheless, with the current data available, almost 40,000 species of protozoans have been identified. No doubt, as the technology improves our methods of observation, better models of classification will be proposed.

With what topic is the passage primarily concerned?

A. Colonies of protozoans

B. Mastigophora

C. Motility in protozoans

D. Characteristics of protozoans

1
28 tháng 10 2019

Đáp án D

(A) Colonies of protozoans: các loại sinh vật đơn bào

(B) Mastigophora: Nhóm Mastigophora

(C) Motility in protozoans: tính chất của sinh vật đơn bào

(D) Characteristics of protozoans: đặc điểm của sinh vật đơn bào

Read the following passage on transport, and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 38 to 42. (1) The protozoans, minute, aquatic creatures each of which consists of a single cell of protoplasm, constitute a classification of the most primitive forms of animal life. They are fantastically diverse, but three major groups may be identified on the basis of their motility. The Mastigophora have one or more long tails, which...
Đọc tiếp

Read the following passage on transport, and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 38 to 42.

(1) The protozoans, minute, aquatic creatures each of which consists of a single cell of protoplasm, constitute a classification of the most primitive forms of animal life. They are fantastically diverse, but three major groups may be identified on the basis of their motility. The Mastigophora have one or more long tails, which they use to project themselves forward. The Ciliata, which use the same basic means for locomotion as the Mastigophora, have a larger number of short tails. The Sarcodina, which include amoebae, float or row themselves about on their crusted bodies.

(2) In addition to their form of movement, several other features discriminate among the three groups of protozoans. For example, at least two nuclei per cell have been identified in the Ciliata, usually a large nucleus that regulates growth but decomposes during reproduction, and a smaller one that contains the genetic code necessary to generate the large nucleus.

(3) Protozoans are considered animals because, unlike pigmented plants to which some protozoans are otherwise almost identical, they do not live on simple organic compounds. Their cell demonstrates all of the major characteristics of the cells of higher animals.

(4) Many species of protozoans collect into colonies, physically connected to each other and responding uniformly to outside stimulae. Current research into this phenomenon, along with investigations carried out with advanced microscopes may necessitate a redefinition of what constitutes protozoans, even calling into question the basic premise that they have only one cell. Nevertheless, with the current data available, almost 40,000 species of protozoans have been identified. No doubt, as the technology improves our methods of observation, better models of classification will be proposed.  

With what topic is the passage primarily concerned?

A. Colonies of protozoans

B. Mastigophora

C. Motility in protozoans

D. Characteristics of protozoans

1
24 tháng 10 2017

Đáp án D

          A. Colonies of protozoans: các loại sinh vật đơn bào

          B. Mastigophora: Nhóm Mastigophora

          C. Motility in protozoans: tính chất của sinh vật đơn bào

          D. Characteristics of protozoans: đặc điểm của sinh vật đơn bào

Read the following passage on transport, and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 43 to 50. (1) The protozoans, minute, aquatic creatures each of which consists of a single cell of protoplasm, constitute a classification of the most primitive forms of animal life. They are fantastically diverse, but three major groups may be identified on the basis of their motility. The Mastigophora have one or more long tails, which...
Đọc tiếp

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

(1) The protozoans, minute, aquatic creatures each of which consists of a single cell of protoplasm, constitute a classification of the most primitive forms of animal life. They are fantastically diverse, but three major groups may be identified on the basis of their motility. The Mastigophora have one or more long tails, which they use to project themselves forward. The Ciliata, which use the same basic means for locomotion as the Mastigophora, have a larger number of short tails. The Sarcodina, which include amoebae, float or row themselves about on their crusted bodies.

(2) In addition to their form of movement, several other features discriminate among the three groups of protozoans. For example, at least two nuclei per cell have been identified in the Ciliata, usually a large nucleus that regulates growth but decomposes during reproduction, and a smaller one that contains the genetic code necessary to generate the large nucleus.

(3) Protozoans are considered animals because, unlike pigmented plants to which some protozoans are otherwise almost identical, they do not live on simple organic compounds. Their cell demonstrates all of the major characteristics of the cells of higher animals.

(4) Many species of protozoans collect into colonies, physically connected to each other and responding uniformly to outside stimulate. Current research into this phenomenon, along with investigations carried out with advanced microscopes may necessitate a redefinition of what constitutes protozoans, even calling into question the basic premise that they have only one cell. Nevertheless, with the current data available, almost 40,000 species of protozoans have been identified. No doubt, as the technology improves our methods of observation, better models of classification will be proposed.

Which of the following statements are NOT true of protozoans?

(A) There are approximately 40,000 species.

(B) They are the most primitive forms of animal life.

(C) They have a large cell and a smaller cell.

(D) They are difficult to observe.

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30 tháng 10 2019

Đáp án C

A: (4) Nevertheless, with the current data available, almost 40,000 species of protozoans have been identified.

B: (1) The protozoans, minute, aquatic creatures each of which consists of a single cell of protoplasm, constitute a classification of the most primitive forms of animal life

D: (4) No doubt, as the technology improves our methods of observation, better models of classification will be proposed.

Dịch bài

(1) Sinh vật đơn bào, loài sinh vật nhỏ, sống trong nước, với mỗi cá thểbao gồm một tế bào duy nhất gồm chất nguyên sinh, tạo thành một nhóm các loài sinh vật nguyên thủy nhất trong thế giới động vật. Chúng rất đa dạng, nhưng nhìn chung có thể chia thành 3 nhóm dựa trên cơ chế di chuyển. Nhóm Mastigophora có một hoặc nhiều đuôi dài, giúp đẩy cơ thể về phía trước. Nhóm Ciliata, có cùng cơ chế vận động như Mastigophora, nhưng nhiều đuôi ngắn hơn. Nhóm Sarcodina, bao gồm trùng amip, trôi nổi hoặc di chuyển trong nước bằng chính cơ thể có lớp bảo vệ bên ngoài của mình

(2) Ngoài hình thức di chuyển, có một số các đặc điểm khác giúp phân biệt 3 nhóm sinh vật đơn bào. Ví dụ, nhóm Ciliata có ít nhất 2 nhân mỗi tế bào, thường một nhân lớn quy định đặc điểm tăng trưởng nhưng phân hủy trong quá trình sinh sản, và một nhân nhỏ hơn có chứa mã di truyền cần thiết để tạo ra nhân lớn.

(3) Sinh vật đơn bào được coi là động vật bởi vì, không giống thực vật có sắc tố mà một số loài sinh vật đơn bào giống y hệt, chúng không sống bằng các hợp chất hữu cơ đơn giản. Tế bào của chúng thể hiện tất cả các đặc điểm chính của tế bào ở động vật bậc cao.

(4) Nhiều loài sinh vật đơn bào tập hợp các cá thể lại với nhau, gọi là các “tập đoàn trùng roi” với mối liên kết chặt chẽ của các bộ phận và phản ứng đồng nhất với kích thích từ bên ngoài. Những nghiên cứu gần đây về hiện tượng này, cùng với những quan sát bằng kính hiển vi cao cấp có lẽ sẽ buộc chúng ta phải định nghĩa lại thế nào là sinh vật đơn bảo, thậm chí phải xem lại định nghĩa cơ bản nhất rằng chúng có thực sự có 1 tế bào hay không. Dù vậy, với các dữ liệu hiện có, các nhà khoa học đã xác định được khoảng 40,000 loại sinh vật đơn bào. Chắc chắn, khi các phương thức quan sát của chúng ta được cải thiện nhờ công nghệ, sẽ có thêm nhiều các mô hình phân loại ưu việt hơn được đưa ra.