Câu hỏi:
26/06/2023 549
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 following questions.
Plants are subject to attack and infection by a remarkable variety of symbiotic species and have evolved a diverse array of mechanisms designed to frustrate the potential colonists. These can be divided into preformed or passive defense mechanisms and inducible or active systems. Passive plant defense comprises physical and chemical barriers that prevent entry of pathogens, such as bacteria, or render tissues unpalatable or toxic to the invader. The external surfaces of plants, in addition to being covered by an epidermis and a waxy cuticle, often carry spiky hairs known as trichomes, which either prevent feeding by insects or may even puncture and kill insect larvae. Other trichomes are sticky and glandular and effectively trap and immobilize insects. If the physical barriers of the plant are breached, then preformed chemicals may inhibit or kill the intruder, and plant tissues contain a diverse array of toxic or potentially toxic substances, such as resins, tannins, glycosides, and alkaloids, many of which are highly effective deterrents to insects that feed on plants. The success of the Colorado beetle in infesting potatoes, for example, seems to be correlated with its high tolerance to alkaloids that normally repel potential pests. Other possible chemical defenses, while not directly toxic to the parasite, may inhibit some essential step in the establishment of a parasitic relationship. For example, glycoproteins in plant cell walls may inactivate enzymes that degrade cell walls. These enzymes are often produced by bacteria and fungi. Active plant defense mechanisms are comparable to the immune system of vertebrate animals, although the cellular and molecular bases are fundamentally different. Both, however, are triggered in reaction to intrusion, implying that the host has some means of recognizing the presence of a foreign organism. The most dramatic example of an inducible plant defense reaction is the hypersensitive response. In the hypersensitive response, cells undergo rapid necrosis ― that is, they become diseased and die ― after being penetrated by a parasite ; the parasite itself subsequently ceases to grow and is therefore restricted to one or a few cells around the entry site. Several theories have been put forward to explain the bases of hypersensitive resistance.
What does the passage mainly discuss?
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 following questions.
Plants are subject to attack and infection by a remarkable variety of symbiotic species and have evolved a diverse array of mechanisms designed to frustrate the potential colonists. These can be divided into preformed or passive defense mechanisms and inducible or active systems. Passive plant defense comprises physical and chemical barriers that prevent entry of pathogens, such as bacteria, or render tissues unpalatable or toxic to the invader. The external surfaces of plants, in addition to being covered by an epidermis and a waxy cuticle, often carry spiky hairs known as trichomes, which either prevent feeding by insects or may even puncture and kill insect larvae. Other trichomes are sticky and glandular and effectively trap and immobilize insects. If the physical barriers of the plant are breached, then preformed chemicals may inhibit or kill the intruder, and plant tissues contain a diverse array of toxic or potentially toxic substances, such as resins, tannins, glycosides, and alkaloids, many of which are highly effective deterrents to insects that feed on plants. The success of the Colorado beetle in infesting potatoes, for example, seems to be correlated with its high tolerance to alkaloids that normally repel potential pests. Other possible chemical defenses, while not directly toxic to the parasite, may inhibit some essential step in the establishment of a parasitic relationship. For example, glycoproteins in plant cell walls may inactivate enzymes that degrade cell walls. These enzymes are often produced by bacteria and fungi. Active plant defense mechanisms are comparable to the immune system of vertebrate animals, although the cellular and molecular bases are fundamentally different. Both, however, are triggered in reaction to intrusion, implying that the host has some means of recognizing the presence of a foreign organism. The most dramatic example of an inducible plant defense reaction is the hypersensitive response. In the hypersensitive response, cells undergo rapid necrosis ― that is, they become diseased and die ― after being penetrated by a parasite ; the parasite itself subsequently ceases to grow and is therefore restricted to one or a few cells around the entry site. Several theories have been put forward to explain the bases of hypersensitive resistance.
What does the passage mainly discuss?
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Trả lời:
Giải bởi Vietjack
Đoạn văn chủ yếu thảo luận về điều gì?
A. Hệ thống miễn dịch của động vật và các cơ chế bảo vệ thực vật khác nhau
B. Cơ chế phòng ngự của thực vật
C. Các lý thuyết về cơ chế bảo vệ thực vật chủ động
D. Sự thành công của ký sinh trùng trong việc chống lại cơ chế bảo vệ thực vật
Chọn đáp án là B
Câu hỏi cùng đoạn
Câu 2:
The phrase "subject to" in line 1 is closest in meaning to
Đáp án chính xác
Lời giải của GV VietJack
Cụm từ "subject to" ở dòng 1 có ý nghĩa gần nhất với
A. hấp dẫn B. tăng cường bởi C. được phân loại bởi D. phải chịu
subject to (a): dễ bị, phải chịu, khó tránh khỏi
=> subject to = susceptible to
Dẫn chứng: Plants are subject to attack and infection by a remarkable variety of symbiotic species and have evolved a diverse array of mechanisms designed to frustrate the potential colonists.
Chọn đáp án là D
Câu 3:
The word "puncture" in line 8 is closest in meaning to
Đáp án chính xác
Lời giải của GV VietJack
Từ "puncture" trong dòng 8 có nghĩa gần nhất với______
A. bao quanh B. nhúm C. xuyên qua D. bao gồm
puncture (v): đâm thủng
=> puncture = pierce
Dẫn chứng: The external surfaces of plants, in addition to being covered by an epidermis and a waxy cuticle, often carry spiky hairs known as trichomes, which either prevent feeding by insects or may even puncture and kill insect larvae.
Chọn đáp án là C
Câu 4:
The word "which" in line 13 refers to
Đáp án chính xác
Lời giải của GV VietJack
Từ "which" trong dòng 13 đề cập đến
A. rào cản B. mô C. chất D. côn trùng
Dẫn chứng: If the physical barriers of the plant are breached, then preformed chemicals may inhibit or kill the intruder, and plant tissues contain a diverse array of toxic or potentially toxic substances, such as resins, tannins, glycosides, and alkaloids, many of which are highly effective deterrents to insects that feed on plants.
Chọn đáp án là C
Câu 5:
Which of the following substances does the author mention as NOT necessarily being toxic to the Colorado beetle?
Đáp án chính xác
Lời giải của GV VietJack
Các chất sau đây tác giả đề cập đến như là không độc đối với bọ cánh cứng Colorado?
A. Alkaloids B. Glycosides C. Nhựa D. taninin
Dẫn chứng: The success of the Colorado beetle in infesting potatoes, for example, seems to be correlated with its high tolerance to alkaloids that normally repel potential pests.
Chọn đáp án là A
Câu 6:
Why does the author mention "glycoproteins" in line 17?
Why does the author mention "glycoproteins" in line 17?
Đáp án chính xác
Lời giải của GV VietJack
Tại sao tác giả đề cập đến "glycoproteins" trong dòng 17?
A. Để minh họa hóa chất hoạt hóa trong phòng vệ thực vật
B. Để nhấn mạnh tầm quan trọng của các rào cản vật lý trong phòng vệ thực vật
C. So sánh cơ chế phòng vệ thực vật với hệ miễn dịch của động vật
D. Giới thiệu việc thảo luận về các cơ chế phòng vệ chủ động trong thực vật
Dẫn chứng: For example, glycoproteins in plant cell walls may inactivate enzymes that degrade cell walls.
These enzymes are often produced by bacteria and fungi.
Chọn đáp án là A
Câu 7:
Where in the passage dose the author describe an active plant-defense reaction?
Đáp án chính xác
Lời giải của GV VietJack
Ở đâu trong đoạn văn, tác giả miêu tả một phản ứng phòng vệ thực vật chủ động?
A. Dòng 1-3 B. Dòng 13-15 C. Dòng 19-23 D. Dòng 4-6
Dẫn chứng: Active plant defense mechanisms are comparable to the immune system of vertebrate animals, although the cellular and molecular bases are fundamentally different. Both, however, are triggered in reaction to intrusion, implying that the host has some means of recognizing the presence of a foreign organism. The most dramatic example of an inducible plant defense reaction is the hypersensitive response.
Chọn đáp án là C
Câu 8:
The passage most probable continues with a discussion of theories on
The passage most probable continues with a discussion of theories on
Đáp án chính xác
Lời giải của GV VietJack
Đoạn văn có thể tiếp tục bàn về giả thuyết gì?
A. Cơ sở của việc phòng vệ thực vật
B. Các nguyên tắc của phản ứng quá mẫn.
C. Các chất hoá học ức chế mối quan hệ ký sinh trùng.
D. Làm thế nào để thực vật tạo ra hóa chất độc hại.
Dẫn chứng: Several theories have been put forward to explain the bases of hypersensitive resistance.
Chọn đáp án là B
Nhà sách VIETJACK:
CÂU HỎI HOT CÙNG CHỦ ĐỀ
Câu 5:
When did the the Pilgrims make a difficult trip to across the ocean from England?
When did the the Pilgrims make a difficult trip to across the ocean from England?
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26/06/2023
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