K
Khách

Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.

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 55 to 64.

The livelihood of each species in the vast and intricate assemblage of living things depends on the existences of other organisms. This interdependence is sometimes subtle, sometimes obvious. Perhaps the most straight forward dependence of one species on another occurs with parasites, organisms that live on or in other living things and derive nutrients directly from them. The parasitic way of life is widespread. A multitude of microorganisms (including viruses and bacteria) and an army of invertebrates - or creatures lacking a spinal column (including crustaceans, insects, and many different types of worms) - make their livings directly at the expense of other creatures. In the face of this onslaught, living things have evolved a variety of defense mechanisms for protecting their bodies from invasion by other organisms.

Certain fungi and even some kinds of bacteria secrete substances known as antibiotics into their external environment. These substances are capable of killing or inhibiting the growth of various kinds of bacteria that also occupy the area, thereby eliminating or reducing the competition for nutrients. The same principle is used in defense against invaders in other groups of organisms. For example, when attacked by disease - causing fungi or bacteria, many kinds of plants produce chemicals that help to ward off the invaders. Members of the animal kingdom have developed a variety of defense mechanisms for dealing with parasites.

Although these mechanisms vary considerably, all major groups of animals are capable of detecting and reacting to the presence of "foreign" cells. In fact, throughout the animal kingdom, from sponges to certain types of worms, shellfish, and all vertebrates (creatures possessing a spinal column), there is evidence that transplants of cells or fragments of tissues into an animal are accepted only if they come from genetically compatible or closely related individuals. The ability to distinguish between "self" and "nonself", while present in all animals, is most efficient among vertebrates, which have developed an immune system as their defense mechanism. The immune system recognizes and takes action against foreign invaders and transplanted tissues that are treated as foreign cells.

According to the passage, a transplant of tissue between genetically incompatible organisms will result in the transplanted tissue ________.

A. becoming a parasite 

B. being treated as an invader

C. developing a new immune system

D. altering its genetic makeup

1
15 tháng 10 2019

Đáp án B

Dựa vào ý của Câu 2 đoạn 3 “all major groups of animals are capable of detecting and reacting to the presence of "foreign" cells”-> việc cấy ghép mô không tương thích sẽ gay ra sự bài trừ “kẻ xâm lăng”

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 55 to 64.The livelihood of each species in the vast and intricate assemblage of living things depends on the existences of other organisms. This interdependence is sometimes subtle, sometimes obvious. Perhaps the most straight forward dependence of one species on another occurs with parasites, organisms that live on or in other living things and derive...
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 55 to 64.

The livelihood of each species in the vast and intricate assemblage of living things depends on the existences of other organisms. This interdependence is sometimes subtle, sometimes obvious. Perhaps the most straight forward dependence of one species on another occurs with parasites, organisms that live on or in other living things and derive nutrients directly from them. The parasitic way of life is widespread. A multitude of microorganisms (including viruses and bacteria) and an army of invertebrates - or creatures lacking a spinal column (including crustaceans, insects, and many different types of worms) - make their livings directly at the expense of other creatures. In the face of this onslaught, living things have evolved a variety of defense mechanisms for protecting their bodies from invasion by other organisms.

Certain fungi and even some kinds of bacteria secrete substances known as antibiotics into their external environment. These substances are capable of killing or inhibiting the growth of various kinds of bacteria that also occupy the area, thereby eliminating or reducing the competition for nutrients. The same principle is used in defense against invaders in other groups of organisms. For example, when attacked by disease - causing fungi or bacteria, many kinds of plants produce chemicals that help to ward off the invaders. Members of the animal kingdom have developed a variety of defense mechanisms for dealing with parasites.

Although these mechanisms vary considerably, all major groups of animals are capable of detecting and reacting to the presence of "foreign" cells. In fact, throughout the animal kingdom, from sponges to certain types of worms, shellfish, and all vertebrates (creatures possessing a spinal column), there is evidence that transplants of cells or fragments of tissues into an animal are accepted only if they come from genetically compatible or closely related individuals. The ability to distinguish between "self" and "nonself", while present in all animals, is most efficient among vertebrates, which have developed an immune system as their defense mechanism. The immune system recognizes and takes action against foreign invaders and transplanted tissues that are treated as foreign cells.

According to the passage, some organisms produce antibiotics in order to ________.

A. prevent disease in humans 

B. aid digestion

C. fight off other organisms

D. create new types of nutrients

1
14 tháng 4 2017

Đáp án C

Đoạn 2 “Certain fungi and even some kinds of bacteria secrete substances known as antibiotics… The same principle is used in defense against invaders in other groups of organisms” một số loại nấm và vi khuẩn tiết ra chất được gọi là kháng sinh… nguyên tắc tương tự với việc dùng để chống lại những kẻ xâm lăng từ các nhóm khác. -> chông lại nhóm sinh vật khác.

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 55 to 64.The livelihood of each species in the vast and intricate assemblage of living things depends on the existences of other organisms. This interdependence is sometimes subtle, sometimes obvious. Perhaps the most straight forward dependence of one species on another occurs with parasites, organisms that live on or in other living things and derive...
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 55 to 64.

The livelihood of each species in the vast and intricate assemblage of living things depends on the existences of other organisms. This interdependence is sometimes subtle, sometimes obvious. Perhaps the most straight forward dependence of one species on another occurs with parasites, organisms that live on or in other living things and derive nutrients directly from them. The parasitic way of life is widespread. A multitude of microorganisms (including viruses and bacteria) and an army of invertebrates - or creatures lacking a spinal column (including crustaceans, insects, and many different types of worms) - make their livings directly at the expense of other creatures. In the face of this onslaught, living things have evolved a variety of defense mechanisms for protecting their bodies from invasion by other organisms.

Certain fungi and even some kinds of bacteria secrete substances known as antibiotics into their external environment. These substances are capable of killing or inhibiting the growth of various kinds of bacteria that also occupy the area, thereby eliminating or reducing the competition for nutrients. The same principle is used in defense against invaders in other groups of organisms. For example, when attacked by disease - causing fungi or bacteria, many kinds of plants produce chemicals that help to ward off the invaders. Members of the animal kingdom have developed a variety of defense mechanisms for dealing with parasites.

Although these mechanisms vary considerably, all major groups of animals are capable of detecting and reacting to the presence of "foreign" cells. In fact, throughout the animal kingdom, from sponges to certain types of worms, shellfish, and all vertebrates (creatures possessing a spinal column), there is evidence that transplants of cells or fragments of tissues into an animal are accepted only if they come from genetically compatible or closely related individuals. The ability to distinguish between "self" and "nonself", while present in all animals, is most efficient among vertebrates, which have developed an immune system as their defense mechanism. The immune system recognizes and takes action against foreign invaders and transplanted tissues that are treated as foreign cells.

The word "intricate" in line 1 is closest in meaning to ________.

A. widespread 

B. difficult

C. complex

D. critical 

1
9 tháng 4 2019

Đáp án C

Intricate= complex= phức tạp, widespread= phổ biến, difficult= khó khăn, critical= chỉ trích.

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 55 to 64.The livelihood of each species in the vast and intricate assemblage of living things depends on the existences of other organisms. This interdependence is sometimes subtle, sometimes obvious. Perhaps the most straight forward dependence of one species on another occurs with parasites, organisms that live on or in other living things and derive...
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 55 to 64.

The livelihood of each species in the vast and intricate assemblage of living things depends on the existences of other organisms. This interdependence is sometimes subtle, sometimes obvious. Perhaps the most straight forward dependence of one species on another occurs with parasites, organisms that live on or in other living things and derive nutrients directly from them. The parasitic way of life is widespread. A multitude of microorganisms (including viruses and bacteria) and an army of invertebrates - or creatures lacking a spinal column (including crustaceans, insects, and many different types of worms) - make their livings directly at the expense of other creatures. In the face of this onslaught, living things have evolved a variety of defense mechanisms for protecting their bodies from invasion by other organisms.

Certain fungi and even some kinds of bacteria secrete substances known as antibiotics into their external environment. These substances are capable of killing or inhibiting the growth of various kinds of bacteria that also occupy the area, thereby eliminating or reducing the competition for nutrients. The same principle is used in defense against invaders in other groups of organisms. For example, when attacked by disease - causing fungi or bacteria, many kinds of plants produce chemicals that help to ward off the invaders. Members of the animal kingdom have developed a variety of defense mechanisms for dealing with parasites.

Although these mechanisms vary considerably, all major groups of animals are capable of detecting and reacting to the presence of "foreign" cells. In fact, throughout the animal kingdom, from sponges to certain types of worms, shellfish, and all vertebrates (creatures possessing a spinal column), there is evidence that transplants of cells or fragments of tissues into an animal are accepted only if they come from genetically compatible or closely related individuals. The ability to distinguish between "self" and "nonself", while present in all animals, is most efficient among vertebrates, which have developed an immune system as their defense mechanism. The immune system recognizes and takes action against foreign invaders and transplanted tissues that are treated as foreign cells.

The expression "an army" in line 5 most likely means ________.

A. an illness 

B. an attack

C. a large number

D. a distinct type

1
17 tháng 12 2019

Đáp án C

An army= một đội quân, a large of number= số lượng lớn, an illness= ốm bệnh, an attack= sự tấn công, a distinct type= một loại khác biệt

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 55 to 64.The livelihood of each species in the vast and intricate assemblage of living things depends on the existences of other organisms. This interdependence is sometimes subtle, sometimes obvious. Perhaps the most straight forward dependence of one species on another occurs with parasites, organisms that live on or in other living things and derive...
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 55 to 64.

The livelihood of each species in the vast and intricate assemblage of living things depends on the existences of other organisms. This interdependence is sometimes subtle, sometimes obvious. Perhaps the most straight forward dependence of one species on another occurs with parasites, organisms that live on or in other living things and derive nutrients directly from them. The parasitic way of life is widespread. A multitude of microorganisms (including viruses and bacteria) and an army of invertebrates - or creatures lacking a spinal column (including crustaceans, insects, and many different types of worms) - make their livings directly at the expense of other creatures. In the face of this onslaught, living things have evolved a variety of defense mechanisms for protecting their bodies from invasion by other organisms.

Certain fungi and even some kinds of bacteria secrete substances known as antibiotics into their external environment. These substances are capable of killing or inhibiting the growth of various kinds of bacteria that also occupy the area, thereby eliminating or reducing the competition for nutrients. The same principle is used in defense against invaders in other groups of organisms. For example, when attacked by disease - causing fungi or bacteria, many kinds of plants produce chemicals that help to ward off the invaders. Members of the animal kingdom have developed a variety of defense mechanisms for dealing with parasites.

Although these mechanisms vary considerably, all major groups of animals are capable of detecting and reacting to the presence of "foreign" cells. In fact, throughout the animal kingdom, from sponges to certain types of worms, shellfish, and all vertebrates (creatures possessing a spinal column), there is evidence that transplants of cells or fragments of tissues into an animal are accepted only if they come from genetically compatible or closely related individuals. The ability to distinguish between "self" and "nonself", while present in all animals, is most efficient among vertebrates, which have developed an immune system as their defense mechanism. The immune system recognizes and takes action against foreign invaders and transplanted tissues that are treated as foreign cells.

According to the passage, the ability to distinguish between "self" and "nonself" enables vertebrates to ________.

A. detect and react to invasion 

B. get rid of antibiotics

C. accept transplanted cells

D. weaken their immune system

1
22 tháng 3 2019

Đáp án A

Câu 2 đoạn 3 “all major groups of animals are capable of detecting and reacting to the presence of "foreign" cells” phần lớp các nhóm động vật có khả năng phát hiện vaf phản ứng lại sự xuất hiện của tế bào ngoại lai.

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 55 to 64.The livelihood of each species in the vast and intricate assemblage of living things depends on the existences of other organisms. This interdependence is sometimes subtle, sometimes obvious. Perhaps the most straight forward dependence of one species on another occurs with parasites, organisms that live on or in other living things and derive...
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 55 to 64.

The livelihood of each species in the vast and intricate assemblage of living things depends on the existences of other organisms. This interdependence is sometimes subtle, sometimes obvious. Perhaps the most straight forward dependence of one species on another occurs with parasites, organisms that live on or in other living things and derive nutrients directly from them. The parasitic way of life is widespread. A multitude of microorganisms (including viruses and bacteria) and an army of invertebrates - or creatures lacking a spinal column (including crustaceans, insects, and many different types of worms) - make their livings directly at the expense of other creatures. In the face of this onslaught, living things have evolved a variety of defense mechanisms for protecting their bodies from invasion by other organisms.

Certain fungi and even some kinds of bacteria secrete substances known as antibiotics into their external environment. These substances are capable of killing or inhibiting the growth of various kinds of bacteria that also occupy the area, thereby eliminating or reducing the competition for nutrients. The same principle is used in defense against invaders in other groups of organisms. For example, when attacked by disease - causing fungi or bacteria, many kinds of plants produce chemicals that help to ward off the invaders. Members of the animal kingdom have developed a variety of defense mechanisms for dealing with parasites.

Although these mechanisms vary considerably, all major groups of animals are capable of detecting and reacting to the presence of "foreign" cells. In fact, throughout the animal kingdom, from sponges to certain types of worms, shellfish, and all vertebrates (creatures possessing a spinal column), there is evidence that transplants of cells or fragments of tissues into an animal are accepted only if they come from genetically compatible or closely related individuals. The ability to distinguish between "self" and "nonself", while present in all animals, is most efficient among vertebrates, which have developed an immune system as their defense mechanism. The immune system recognizes and takes action against foreign invaders and transplanted tissues that are treated as foreign cells.

The paragraph following the passage most probably discusses ________.

A. how the immune system in vertebrates fights off foreign cells 

B. different types of bacteria and lung

C. how vertebrates and invertebrates differ

D. examples of different groups of organisms

1
9 tháng 1 2017

Đáp án A

Đoạn cuối nói giới thiệu về hệ thống miễn dịch của sống vật có xương sống-> đoạn sau sẽ nói về cách mà hệ thông này hoạt động chống lại các tế bào ngoại lai.

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 55 to 64.The livelihood of each species in the vast and intricate assemblage of living things depends on the existences of other organisms. This interdependence is sometimes subtle, sometimes obvious. Perhaps the most straight forward dependence of one species on another occurs with parasites, organisms that live on or in other living things and derive...
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 55 to 64.

The livelihood of each species in the vast and intricate assemblage of living things depends on the existences of other organisms. This interdependence is sometimes subtle, sometimes obvious. Perhaps the most straight forward dependence of one species on another occurs with parasites, organisms that live on or in other living things and derive nutrients directly from them. The parasitic way of life is widespread. A multitude of microorganisms (including viruses and bacteria) and an army of invertebrates - or creatures lacking a spinal column (including crustaceans, insects, and many different types of worms) - make their livings directly at the expense of other creatures. In the face of this onslaught, living things have evolved a variety of defense mechanisms for protecting their bodies from invasion by other organisms.

Certain fungi and even some kinds of bacteria secrete substances known as antibiotics into their external environment. These substances are capable of killing or inhibiting the growth of various kinds of bacteria that also occupy the area, thereby eliminating or reducing the competition for nutrients. The same principle is used in defense against invaders in other groups of organisms. For example, when attacked by disease - causing fungi or bacteria, many kinds of plants produce chemicals that help to ward off the invaders. Members of the animal kingdom have developed a variety of defense mechanisms for dealing with parasites.

Although these mechanisms vary considerably, all major groups of animals are capable of detecting and reacting to the presence of "foreign" cells. In fact, throughout the animal kingdom, from sponges to certain types of worms, shellfish, and all vertebrates (creatures possessing a spinal column), there is evidence that transplants of cells or fragments of tissues into an animal are accepted only if they come from genetically compatible or closely related individuals. The ability to distinguish between "self" and "nonself", while present in all animals, is most efficient among vertebrates, which have developed an immune system as their defense mechanism. The immune system recognizes and takes action against foreign invaders and transplanted tissues that are treated as foreign cells.

All of the following are defined in the passage EXCEPT ________.

A. parasites (paragraph 1) 

B. invertebrates (paragraph 1)

C. nutrients (paragraph 2)

D. vertebrates (paragraph 3)

1
16 tháng 1 2017

Đáp án C

“parasites, organisms that live on or in other living things and derive nutrients directly from them”- sinh vật sống trên hoặc trong các sinh vật khác và lấy được các chất dinh dưỡng trực tiếp từ chúng. “invertebrates - or creatures lacking a spinal column (including crustaceans, insects, and many different types of worms)” –động vật không xương sống- sinh vật thiếu cột sống ( bao gồm động vật giáp xác, côn trùng, và nhiều loại khác nhau của sâu”, vertebrates (creatures possessing a spinal column) – động vật có xương sống ( các sinh vật sở hữu 1 cột sống)-> loại trừ đáp án A, B, D.

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 55 to 64.The livelihood of each species in the vast and intricate assemblage of living things depends on the existences of other organisms. This interdependence is sometimes subtle, sometimes obvious. Perhaps the most straight forward dependence of one species on another occurs with parasites, organisms that live on or in other living things and derive...
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 55 to 64.

The livelihood of each species in the vast and intricate assemblage of living things depends on the existences of other organisms. This interdependence is sometimes subtle, sometimes obvious. Perhaps the most straight forward dependence of one species on another occurs with parasites, organisms that live on or in other living things and derive nutrients directly from them. The parasitic way of life is widespread. A multitude of microorganisms (including viruses and bacteria) and an army of invertebrates - or creatures lacking a spinal column (including crustaceans, insects, and many different types of worms) - make their livings directly at the expense of other creatures. In the face of this onslaught, living things have evolved a variety of defense mechanisms for protecting their bodies from invasion by other organisms.

Certain fungi and even some kinds of bacteria secrete substances known as antibiotics into their external environment. These substances are capable of killing or inhibiting the growth of various kinds of bacteria that also occupy the area, thereby eliminating or reducing the competition for nutrients. The same principle is used in defense against invaders in other groups of organisms. For example, when attacked by disease - causing fungi or bacteria, many kinds of plants produce chemicals that help to ward off the invaders. Members of the animal kingdom have developed a variety of defense mechanisms for dealing with parasites.

Although these mechanisms vary considerably, all major groups of animals are capable of detecting and reacting to the presence of "foreign" cells. In fact, throughout the animal kingdom, from sponges to certain types of worms, shellfish, and all vertebrates (creatures possessing a spinal column), there is evidence that transplants of cells or fragments of tissues into an animal are accepted only if they come from genetically compatible or closely related individuals. The ability to distinguish between "self" and "nonself", while present in all animals, is most efficient among vertebrates, which have developed an immune system as their defense mechanism. The immune system recognizes and takes action against foreign invaders and transplanted tissues that are treated as foreign cells.

The word "vary" in line 14 could best be replaced by “________”.

A. endure 

B. differ

C. balance

D. contribute

1
20 tháng 3 2017

Đáp án B

Vary= thay đổi, differ= khác, endure= chịu đựng, balance= cân bằng, contribute=góp phần.

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 55 to 64.The livelihood of each species in the vast and intricate assemblage of living things depends on the existences of other organisms. This interdependence is sometimes subtle, sometimes obvious. Perhaps the most straight forward dependence of one species on another occurs with parasites, organisms that live on or in other living things and derive...
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 55 to 64.

The livelihood of each species in the vast and intricate assemblage of living things depends on the existences of other organisms. This interdependence is sometimes subtle, sometimes obvious. Perhaps the most straight forward dependence of one species on another occurs with parasites, organisms that live on or in other living things and derive nutrients directly from them. The parasitic way of life is widespread. A multitude of microorganisms (including viruses and bacteria) and an army of invertebrates - or creatures lacking a spinal column (including crustaceans, insects, and many different types of worms) - make their livings directly at the expense of other creatures. In the face of this onslaught, living things have evolved a variety of defense mechanisms for protecting their bodies from invasion by other organisms.

Certain fungi and even some kinds of bacteria secrete substances known as antibiotics into their external environment. These substances are capable of killing or inhibiting the growth of various kinds of bacteria that also occupy the area, thereby eliminating or reducing the competition for nutrients. The same principle is used in defense against invaders in other groups of organisms. For example, when attacked by disease - causing fungi or bacteria, many kinds of plants produce chemicals that help to ward off the invaders. Members of the animal kingdom have developed a variety of defense mechanisms for dealing with parasites.

Although these mechanisms vary considerably, all major groups of animals are capable of detecting and reacting to the presence of "foreign" cells. In fact, throughout the animal kingdom, from sponges to certain types of worms, shellfish, and all vertebrates (creatures possessing a spinal column), there is evidence that transplants of cells or fragments of tissues into an animal are accepted only if they come from genetically compatible or closely related individuals. The ability to distinguish between "self" and "nonself", while present in all animals, is most efficient among vertebrates, which have developed an immune system as their defense mechanism. The immune system recognizes and takes action against foreign invaders and transplanted tissues that are treated as foreign cells.

What does the passage mainly discuss?

A. how antibiotics work to cure disease 

B. how organisms react to invaders

C. how the immune systems of vertebrates developed

D. how parasites reproduce

1
29 tháng 12 2018

Đáp án B

Dịch đáp án:

A- cách sinh sản ở ký sinh trùng,

B- cách sinh vật phản ứng với kẻ thủ,

C- cách kháng sinh hoạt động để chữa bệnh,

D-cách phát triển hệ thống miễn dịch của động vật có xương sống.

 

Đoạn 1 nói về mối quan hệ giữa các loài, đoạn  là sự tự vệ của nấm và vi khuẩn, đoạn 3 là hệ thông bảo vệ của động vật, đoạn cuối là giới thiệu về hệ thống miễn dịch của sống vật có xương sống -> đáp án B là nội dung chính của bài.

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 55 to 64.The livelihood of each species in the vast and intricate assemblage of living things depends on the existences of other organisms. This interdependence is sometimes subtle, sometimes obvious. Perhaps the most straight forward dependence of one species on another occurs with parasites, organisms that live on or in other living things and derive...
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 55 to 64.

The livelihood of each species in the vast and intricate assemblage of living things depends on the existences of other organisms. This interdependence is sometimes subtle, sometimes obvious. Perhaps the most straight forward dependence of one species on another occurs with parasites, organisms that live on or in other living things and derive nutrients directly from them. The parasitic way of life is widespread. A multitude of microorganisms (including viruses and bacteria) and an army of invertebrates - or creatures lacking a spinal column (including crustaceans, insects, and many different types of worms) - make their livings directly at the expense of other creatures. In the face of this onslaught, living things have evolved a variety of defense mechanisms for protecting their bodies from invasion by other organisms.

Certain fungi and even some kinds of bacteria secrete substances known as antibiotics into their external environment. These substances are capable of killing or inhibiting the growth of various kinds of bacteria that also occupy the area, thereby eliminating or reducing the competition for nutrients. The same principle is used in defense against invaders in other groups of organisms. For example, when attacked by disease - causing fungi or bacteria, many kinds of plants produce chemicals that help to ward off the invaders. Members of the animal kingdom have developed a variety of defense mechanisms for dealing with parasites.

Although these mechanisms vary considerably, all major groups of animals are capable of detecting and reacting to the presence of "foreign" cells. In fact, throughout the animal kingdom, from sponges to certain types of worms, shellfish, and all vertebrates (creatures possessing a spinal column), there is evidence that transplants of cells or fragments of tissues into an animal are accepted only if they come from genetically compatible or closely related individuals. The ability to distinguish between "self" and "nonself", while present in all animals, is most efficient among vertebrates, which have developed an immune system as their defense mechanism. The immune system recognizes and takes action against foreign invaders and transplanted tissues that are treated as foreign cells.

The word "they" in line 17 refers to ________.

A. individuals 

B. vertebrates

C. transplants

D. sponges, worms and shellfish

1
26 tháng 8 2017

Đáp án C

Individual= cá thể, vertebrate= động vật có xương sống, transplant = cấy ghép, sponges, worms and shellfish= bọt biển, sâu và một số hải sản có vỏ. Dòng 6 đoạn 3 “transplants of cells or fragments of tissues into an animal are accepted only if they come from genetically compatible” việc cấy ghép tế bào hoặc các mô vào động vật chỉ được chấp nhận khi nó tương thích về di truyền-> việc cấy ghép.