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Read the passage and mark the letter A, B, C or D to answer the following questions.

Most sources of illumination generate light over an appreciable period, and indeed if an object is lit for a very brief time (1ess that 1/25 second), the human eye will not react in time to see the object. A photographic emulsion - that is, a light-sensitive coating on photographic film, paper, or glass - will, however, record much shorter bursts of light. A photographic flash can therefore be used to capture high-speed movement on film as well as to correct deficiencies of the normal surrounding lighting. Photoflash is now generated electronically, but the earliest form, first used in 1864, was a paper bag containing

magnesium wire and some oxygen-rich substance, such as potassium chlorate. When the bag was ignited, the metal burned with an intense flash. A contemporary observer reported that "this quite unsafe device seems to have done nothing worse that engulf the room in dense smoke and lead to pictures of dubious quality and odd poses.”

The evolution of the photoflash was slow, flashbulbs, containing fine wire made of a metal, such as magnesium or aluminum, capable of being ignited in an atmosphere of pure oxygen at low pressure, were introduced only in the 1920's. In the earliest type, the metal was separated from the oxygen by a thin glass bulb. The flash was fired by piercing the bulb and allowing the oxygen to come into contact with the metal, which ignited spontaneously. Later bulbs were fired by an electric battery, which heated the wire by passing a small current through it. Other combinations, such as the pairing of oxygen difluoride with zirconium, have also been used. In each case enough energy is given out to heat the oxidizable metal momentarily to a white hot emission of visible light. The smoke particles are so small that they cool rapidly; but since they are white, they contribute to the brilliance by reflecting the light from their still glowing neighbors. A slightly bigger form of the metal will burn for a longer time.

According to the passage, an advantage of using a photoflash is that it _____. 

A. can produce repeated bursts of light

B. intensities colors in photographs 

C. is short enough not to bother human eyes 

D. supplements existing lighting

1
20 tháng 10 2018

Đáp án D

Theo đoạn văn, một lợi ích của việc sử dụng đèn flash là nó _______.

A. có thể tạo ra những chùm sáng lặp đi lặp lại

B. tăng cường màu sắc trong các bức ảnh

C. đủ nhanh để không làm nheo mắt người được chụp ảnh

D. bổ sung ánh sáng hiện có

Dựa vào thông tin trong đoạn 1:

Tạm dịch: “A photographic emulsion - that is, a light-sensitive coating on photographic film, paper, or glass - will, however, record much shorter bursts of light. A photographic flash can therefore be used to capture high-speed movement on film as well as to correct deficiencies of the normal surrounding lighting." (Tuy nhiên, chất tráng phim dùng trong nhiếp ảnh - là một lớp phủ nhạy với ánh sáng trên phim ảnh, gidy hoặc thủy tinh - sẽ ghi lại những chùm ánh sáng ngắn hơn nhiều. Do đó, đèn flash chụp ảnh có thể được sử dụng để ghi lại chuyển động tốc độ cao trên phim cũng như điều chỉnh sự thiếu hụt của ánh sáng xung quanh)

Read the passage and mark the letter A, B, C or D to answer the following questions.Most sources of illumination generate light over an appreciable period, and indeed if an object is lit for a very brief time (1ess that 1/25 second), the human eye will not react in time to see the object. A photographic emulsion - that is, a light-sensitive coating on photographic film, paper, or glass - will, however, record much shorter bursts of light. A photographic flash can therefore be used to capture...
Đọc tiếp

Read the passage and mark the letter A, B, C or D to answer the following questions.

Most sources of illumination generate light over an appreciable period, and indeed if an object is lit for a very brief time (1ess that 1/25 second), the human eye will not react in time to see the object. A photographic emulsion - that is, a light-sensitive coating on photographic film, paper, or glass - will, however, record much shorter bursts of light. A photographic flash can therefore be used to capture high-speed movement on film as well as to correct deficiencies of the normal surrounding lighting. Photoflash is now generated electronically, but the earliest form, first used in 1864, was a paper bag containing

magnesium wire and some oxygen-rich substance, such as potassium chlorate. When the bag was ignited, the metal burned with an intense flash. A contemporary observer reported that "this quite unsafe device seems to have done nothing worse that engulf the room in dense smoke and lead to pictures of dubious quality and odd poses.”

The evolution of the photoflash was slow, flashbulbs, containing fine wire made of a metal, such as magnesium or aluminum, capable of being ignited in an atmosphere of pure oxygen at low pressure, were introduced only in the 1920's. In the earliest type, the metal was separated from the oxygen by a thin glass bulb. The flash was fired by piercing the bulb and allowing the oxygen to come into contact with the metal, which ignited spontaneously. Later bulbs were fired by an electric battery, which heated the wire by passing a small current through it. Other combinations, such as the pairing of oxygen difluoride with zirconium, have also been used. In each case enough energy is given out to heat the oxidizable metal momentarily to a white hot emission of visible light. The smoke particles are so small that they cool rapidly; but since they are white, they contribute to the brilliance by reflecting the light from their still glowing neighbors. A slightly bigger form of the metal will burn for a longer time.

Which of the following is TRUE about the function of the glass in the first flashbulbs? 

A. It produced the spark that initiated the flash. 

B. It magnified the light produced by the flash. 

C. It protected the photographer from the heat of the flash. 

D. It kept the metal and oxygen apart before the flash.

1
30 tháng 7 2017

Đáp án D

Điều nào dưới đây là ĐÚNG về chức năng thủy tinh trong chiếc bóng đèn flash đầu tiên được sử dụng?

A. Nó tạo ra tia lửa để khởi động đèn flash

B. Nó phóng đại ánh sáng do đèn flash tạo ra

C. Nó bảo vệ các nhiếp ảnh gia khỏi sức nóng của đèn flash

D. Nó giữ cho kim loại và oxy tách rời nhau trước khi đèn nháy

Dựa vào thông tin trong đoạn 2:

"In the earliest type, the metal was separated from the oxygen by a thin glass bulb” (Ở loại bóng đèn lần đầu được sử dụng, kim loại được tách rời khỏi oxy bằng một bóng đèn thủy tinh mỏng.)

Read the passage and mark the letter A, B, C or D to answer the following questions.Most sources of illumination generate light over an appreciable period, and indeed if an object is lit for a very brief time (1ess that 1/25 second), the human eye will not react in time to see the object. A photographic emulsion - that is, a light-sensitive coating on photographic film, paper, or glass - will, however, record much shorter bursts of light. A photographic flash can therefore be used to capture...
Đọc tiếp

Read the passage and mark the letter A, B, C or D to answer the following questions.

Most sources of illumination generate light over an appreciable period, and indeed if an object is lit for a very brief time (1ess that 1/25 second), the human eye will not react in time to see the object. A photographic emulsion - that is, a light-sensitive coating on photographic film, paper, or glass - will, however, record much shorter bursts of light. A photographic flash can therefore be used to capture high-speed movement on film as well as to correct deficiencies of the normal surrounding lighting. Photoflash is now generated electronically, but the earliest form, first used in 1864, was a paper bag containing

magnesium wire and some oxygen-rich substance, such as potassium chlorate. When the bag was ignited, the metal burned with an intense flash. A contemporary observer reported that "this quite unsafe device seems to have done nothing worse that engulf the room in dense smoke and lead to pictures of dubious quality and odd poses.”

The evolution of the photoflash was slow, flashbulbs, containing fine wire made of a metal, such as magnesium or aluminum, capable of being ignited in an atmosphere of pure oxygen at low pressure, were introduced only in the 1920's. In the earliest type, the metal was separated from the oxygen by a thin glass bulb. The flash was fired by piercing the bulb and allowing the oxygen to come into contact with the metal, which ignited spontaneously. Later bulbs were fired by an electric battery, which heated the wire by passing a small current through it. Other combinations, such as the pairing of oxygen difluoride with zirconium, have also been used. In each case enough energy is given out to heat the oxidizable metal momentarily to a white hot emission of visible light. The smoke particles are so small that they cool rapidly; but since they are white, they contribute to the brilliance by reflecting the light from their still glowing neighbors. A slightly bigger form of the metal will burn for a longer time.

 The word "ignited" in paragraph 1 is closest in meaning to ______.

A. set on fire

B. cut into 

C. opened 

D. shaken

1
1 tháng 8 2019

Đáp án A

Từ "ignited” trong đoạn 1 gần nghĩa nhất với __________.

A. đốt cháy          B. cắt                     C. mở                            D. rung

Căn cứ vào thông tin đoạn 1:

Tạm dịch: “When the bag was ignited, the metal burned with an intense flash." (Khi chiếc túi được đánh lửa, kim loại bị đốt cháy với ánh sáng dữ dội.)

Read the passage and mark the letter A, B, C or D to answer the following questions.Most sources of illumination generate light over an appreciable period, and indeed if an object is lit for a very brief time (1ess that 1/25 second), the human eye will not react in time to see the object. A photographic emulsion - that is, a light-sensitive coating on photographic film, paper, or glass - will, however, record much shorter bursts of light. A photographic flash can therefore be used to capture...
Đọc tiếp

Read the passage and mark the letter A, B, C or D to answer the following questions.

Most sources of illumination generate light over an appreciable period, and indeed if an object is lit for a very brief time (1ess that 1/25 second), the human eye will not react in time to see the object. A photographic emulsion - that is, a light-sensitive coating on photographic film, paper, or glass - will, however, record much shorter bursts of light. A photographic flash can therefore be used to capture high-speed movement on film as well as to correct deficiencies of the normal surrounding lighting. Photoflash is now generated electronically, but the earliest form, first used in 1864, was a paper bag containing

magnesium wire and some oxygen-rich substance, such as potassium chlorate. When the bag was ignited, the metal burned with an intense flash. A contemporary observer reported that "this quite unsafe device seems to have done nothing worse that engulf the room in dense smoke and lead to pictures of dubious quality and odd poses.”

The evolution of the photoflash was slow, flashbulbs, containing fine wire made of a metal, such as magnesium or aluminum, capable of being ignited in an atmosphere of pure oxygen at low pressure, were introduced only in the 1920's. In the earliest type, the metal was separated from the oxygen by a thin glass bulb. The flash was fired by piercing the bulb and allowing the oxygen to come into contact with the metal, which ignited spontaneously. Later bulbs were fired by an electric battery, which heated the wire by passing a small current through it. Other combinations, such as the pairing of oxygen difluoride with zirconium, have also been used. In each case enough energy is given out to heat the oxidizable metal momentarily to a white hot emission of visible light. The smoke particles are so small that they cool rapidly; but since they are white, they contribute to the brilliance by reflecting the light from their still glowing neighbors. A slightly bigger form of the metal will burn for a longer time.

What is the best title for the passage? 

A. The history of the photoflash 

B. Theories about how the eye reacts to light 

C. The technology of modern photography 

D. The dangers of using the early photoflash

1
7 tháng 1 2018

Đáp án A

Chủ đề về INVENTIONS

Tiêu đề chính của đoạn văn là gì?

A. Lịch sử của đèn nháy (đèn flash)

B. Các học thuyết về cách mà mắt phản ứng lại ánh sáng

C. Công nghệ chụp ảnh hiện đại

D. Những nguy hiểm của việc sử dụng đèn flash thủa ban đầu

Căn cứ vào các thông tin ở cả đoạn 1 và 2:

- “Photoflash is now generated electronically, but the earliest form, first used in 1864, was a paper bag containing magnesium wire and some oxygen-rich substance, such as potassium chlorate." (Đèn flash ngày nay được tạo ra hàng công nghệ tự động hóa, nhưng thủa sơ khai, khi lần đầu tiên được sử dụng vào năm 1864, nó chỉ là một túi giấy có chứa dây dẫn magiê và một số chất giàu oxy, như kali clorat.)

- “The evolution of the photoflash was slow, flashbulbs, containing fine wire made of a metal, such as magnesium or aluminum, capable of being ignited in an atmosphere of pure oxygen at low pressure, were introduced only in the 1920's." (Sự phát triển của đèn flash diễn ra chậm, các bóng đèn nháy, chứa dây dẫn làm bằng kim loại, như magiê hoặc nhóm, có khả năng bị đốt cháy trong môi trường chứa oxy tinh khiết ở áp suất thấp, chỉ được phát minh vào những năm 1920.)

Như vậy có thể thấy xuyên suốt bài đọc là lịch sử ra đời và phát triển của đèn flash => Do do, đáp án là A

Read the passage and mark the letter A, B, C or D to answer the following questions.Most sources of illumination generate light over an appreciable period, and indeed if an object is lit for a very brief time (1ess that 1/25 second), the human eye will not react in time to see the object. A photographic emulsion - that is, a light-sensitive coating on photographic film, paper, or glass - will, however, record much shorter bursts of light. A photographic flash can therefore be used to capture...
Đọc tiếp

Read the passage and mark the letter A, B, C or D to answer the following questions.

Most sources of illumination generate light over an appreciable period, and indeed if an object is lit for a very brief time (1ess that 1/25 second), the human eye will not react in time to see the object. A photographic emulsion - that is, a light-sensitive coating on photographic film, paper, or glass - will, however, record much shorter bursts of light. A photographic flash can therefore be used to capture high-speed movement on film as well as to correct deficiencies of the normal surrounding lighting. Photoflash is now generated electronically, but the earliest form, first used in 1864, was a paper bag containing

magnesium wire and some oxygen-rich substance, such as potassium chlorate. When the bag was ignited, the metal burned with an intense flash. A contemporary observer reported that "this quite unsafe device seems to have done nothing worse that engulf the room in dense smoke and lead to pictures of dubious quality and odd poses.”

The evolution of the photoflash was slow, flashbulbs, containing fine wire made of a metal, such as magnesium or aluminum, capable of being ignited in an atmosphere of pure oxygen at low pressure, were introduced only in the 1920's. In the earliest type, the metal was separated from the oxygen by a thin glass bulb. The flash was fired by piercing the bulb and allowing the oxygen to come into contact with the metal, which ignited spontaneously. Later bulbs were fired by an electric battery, which heated the wire by passing a small current through it. Other combinations, such as the pairing of oxygen difluoride with zirconium, have also been used. In each case enough energy is given out to heat the oxidizable metal momentarily to a white hot emission of visible light. The smoke particles are so small that they cool rapidly; but since they are white, they contribute to the brilliance by reflecting the light from their still glowing neighbors. A slightly bigger form of the metal will burn for a longer time.

The word "momentarily"  in paragraph 2 is closet in meaning to ______. 

A. effortlessly

B. briefly 

C. electronically 

D. gradually

1
24 tháng 1 2018

Đáp án B

Từ “momentarily” trong đoạn 2 gần nghĩa với từ ___________.

A. effortlessly /'efətlisli/ (adv): một cách dễ dàng

B. briefly /'bri:fli/ (adv): một cách ngắn gọn

C. electronically /ilek'trɔnikli/ (adv): bằng điện tử

D. gradually /'grædjuəli/ (adv): dần dần, từ từ

Căn cứ vào ngữ cảnh đoạn 2:

“In each case, enough energy is given out to heat the oxidizable metal momentarily to a white hot emission of Visible light.” (Trong mỗi trường hợp, một năng lượng vừa đủ được cung cấp để đốt cháy kim loại có thể oxy hóa trong giây lát để phát ra ánh sáng nóng trắng mà mắt thường có thể thấy được.)

=> Do đó, đáp án là B

Read the passage and mark the letter A, B, C or D to answer the following questions.Most sources of illumination generate light over an appreciable period, and indeed if an object is lit for a very brief time (1ess that 1/25 second), the human eye will not react in time to see the object. A photographic emulsion - that is, a light-sensitive coating on photographic film, paper, or glass - will, however, record much shorter bursts of light. A photographic flash can therefore be used to capture...
Đọc tiếp

Read the passage and mark the letter A, B, C or D to answer the following questions.

Most sources of illumination generate light over an appreciable period, and indeed if an object is lit for a very brief time (1ess that 1/25 second), the human eye will not react in time to see the object. A photographic emulsion - that is, a light-sensitive coating on photographic film, paper, or glass - will, however, record much shorter bursts of light. A photographic flash can therefore be used to capture high-speed movement on film as well as to correct deficiencies of the normal surrounding lighting. Photoflash is now generated electronically, but the earliest form, first used in 1864, was a paper bag containing

magnesium wire and some oxygen-rich substance, such as potassium chlorate. When the bag was ignited, the metal burned with an intense flash. A contemporary observer reported that "this quite unsafe device seems to have done nothing worse that engulf the room in dense smoke and lead to pictures of dubious quality and odd poses.”

The evolution of the photoflash was slow, flashbulbs, containing fine wire made of a metal, such as magnesium or aluminum, capable of being ignited in an atmosphere of pure oxygen at low pressure, were introduced only in the 1920's. In the earliest type, the metal was separated from the oxygen by a thin glass bulb. The flash was fired by piercing the bulb and allowing the oxygen to come into contact with the metal, which ignited spontaneously. Later bulbs were fired by an electric battery, which heated the wire by passing a small current through it. Other combinations, such as the pairing of oxygen difluoride with zirconium, have also been used. In each case enough energy is given out to heat the oxidizable metal momentarily to a white hot emission of visible light. The smoke particles are so small that they cool rapidly; but since they are white, they contribute to the brilliance by reflecting the light from their still glowing neighbors. A slightly bigger form of the metal will burn for a longer time.

Which of the following most accurately reflects the main idea of the last paragraph? 

A. The time when photoflash was first used. 

B. How metal burns in an atmosphere of pure oxygen. 

C. How early photoflash worked. 

D. The role of glass in flashbulb.

1
21 tháng 8 2017

Đáp án C

Câu nào dưới đây phản ảnh chính xác nhất ý chính của đoạn cuối?

A. Đèn flash lần đầu tiên được sử dụng là khi nào.

B. Làm sao kim loại cháy được trong môi trường oxy tinh khiết.

C. Cách thức hoạt động của đèn flash đời đầu.

D. Vai trò của thủy tinh trong bóng đèn flash.

Căn cứ vào thông tin trong đoạn cuối: đã được trích dẫn trong các câu 38, 39, và 40, ta dễ dàng nhận thấy đoạn này nói về cách tạo ra tia flash ở loại đèn flash đời đầu tiên.

Read the passage and mark the letter A, B, C or D to answer the following questions.Most sources of illumination generate light over an appreciable period, and indeed if an object is lit for a very brief time (1ess that 1/25 second), the human eye will not react in time to see the object. A photographic emulsion - that is, a light-sensitive coating on photographic film, paper, or glass - will, however, record much shorter bursts of light. A photographic flash can therefore be used to capture...
Đọc tiếp

Read the passage and mark the letter A, B, C or D to answer the following questions.

Most sources of illumination generate light over an appreciable period, and indeed if an object is lit for a very brief time (1ess that 1/25 second), the human eye will not react in time to see the object. A photographic emulsion - that is, a light-sensitive coating on photographic film, paper, or glass - will, however, record much shorter bursts of light. A photographic flash can therefore be used to capture high-speed movement on film as well as to correct deficiencies of the normal surrounding lighting. Photoflash is now generated electronically, but the earliest form, first used in 1864, was a paper bag containing

magnesium wire and some oxygen-rich substance, such as potassium chlorate. When the bag was ignited, the metal burned with an intense flash. A contemporary observer reported that "this quite unsafe device seems to have done nothing worse that engulf the room in dense smoke and lead to pictures of dubious quality and odd poses.”

The evolution of the photoflash was slow, flashbulbs, containing fine wire made of a metal, such as magnesium or aluminum, capable of being ignited in an atmosphere of pure oxygen at low pressure, were introduced only in the 1920's. In the earliest type, the metal was separated from the oxygen by a thin glass bulb. The flash was fired by piercing the bulb and allowing the oxygen to come into contact with the metal, which ignited spontaneously. Later bulbs were fired by an electric battery, which heated the wire by passing a small current through it. Other combinations, such as the pairing of oxygen difluoride with zirconium, have also been used. In each case enough energy is given out to heat the oxidizable metal momentarily to a white hot emission of visible light. The smoke particles are so small that they cool rapidly; but since they are white, they contribute to the brilliance by reflecting the light from their still glowing neighbors. A slightly bigger form of the metal will burn for a longer time.

According to the passage, what helps a flashbulb burn longer? 

A. thicker wire

B. more oxygen 

C. thinner glass 

D. continuous electricity

1
23 tháng 8 2019

Đáp án A

Theo bài văn, điều gì giúp cho bóng đèn flash có thể cháy lâu hơn?

A. dây dẫn dày hơn                                   B. nhiều Oxy hơn

C. kính mỏng hơn                                       D. điện thường xuyên

Căn cứ vào câu cuối của bài:

“A slightly bigger form of the metal will burn for a longer time.” (Một mẫu kim loại lớn hơn chút xíu sẽ cháy lâu hơn).

Trong suốt bài đọc, kim loại chính là dây dẫn trong bóng đèn flash.

Read the passage and mark the letter A, B, C or D to answer the following questions.Most sources of illumination generate light over an appreciable period, and indeed if an object is lit for a very brief time (1ess that 1/25 second), the human eye will not react in time to see the object. A photographic emulsion - that is, a light-sensitive coating on photographic film, paper, or glass - will, however, record much shorter bursts of light. A photographic flash can therefore be used to capture...
Đọc tiếp

Read the passage and mark the letter A, B, C or D to answer the following questions.

Most sources of illumination generate light over an appreciable period, and indeed if an object is lit for a very brief time (1ess that 1/25 second), the human eye will not react in time to see the object. A photographic emulsion - that is, a light-sensitive coating on photographic film, paper, or glass - will, however, record much shorter bursts of light. A photographic flash can therefore be used to capture high-speed movement on film as well as to correct deficiencies of the normal surrounding lighting. Photoflash is now generated electronically, but the earliest form, first used in 1864, was a paper bag containing

magnesium wire and some oxygen-rich substance, such as potassium chlorate. When the bag was ignited, the metal burned with an intense flash. A contemporary observer reported that "this quite unsafe device seems to have done nothing worse that engulf the room in dense smoke and lead to pictures of dubious quality and odd poses.”

The evolution of the photoflash was slow, flashbulbs, containing fine wire made of a metal, such as magnesium or aluminum, capable of being ignited in an atmosphere of pure oxygen at low pressure, were introduced only in the 1920's. In the earliest type, the metal was separated from the oxygen by a thin glass bulb. The flash was fired by piercing the bulb and allowing the oxygen to come into contact with the metal, which ignited spontaneously. Later bulbs were fired by an electric battery, which heated the wire by passing a small current through it. Other combinations, such as the pairing of oxygen difluoride with zirconium, have also been used. In each case enough energy is given out to heat the oxidizable metal momentarily to a white hot emission of visible light. The smoke particles are so small that they cool rapidly; but since they are white, they contribute to the brilliance by reflecting the light from their still glowing neighbors. A slightly bigger form of the metal will burn for a longer time.

The word "it" in paragraph 2 refers to _____. 

A. oxygen

B. battery 

C. wire 

D. current

1
23 tháng 11 2019

Đáp án C

Từ "it” trong đoạn 2 đề cập đến

A. khí Oxy           B. Pin                    C. dây dẫn                    D. dòng điện

Căn cứ vào thông tin đoạn 2:

“The flash was fired by piercing the bulb and allowing the oxygen to come into contact with the metal, which ignited spontaneously. Later bulbs were fired by an electric battery, which heated the wire by passing a small current through it.” (Đèn flash được đốt sáng bằng cách xuyên thủng bóng đèn và cho phép oxy tiếp xúc với kim loại, khiến nó tự bốc cháy. Sau đó, những bóng đèn thắp sáng bởi một pin điện, pin này làm nóng dây dẫn bằng cách truyền một dòng điện nhỏ qua nó - tức là dây dẫn.)

Các đáp án còn lại có xuất hiện trong bài nhưng không chính xác nên ta

=> Do đó, đáp án là 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 36 to 42. Light from a living plant or animal is called bioluminescence, or cold light, to distinguish it from incandescence or heat-generating light. Life forms could not produce incandescent light without being burned. Their light is produced in chemicals combining in such a way that little or no measurable heat is produced, and the life forms generating it are unharmed....
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 36 to 42.

Light from a living plant or animal is called bioluminescence, or cold light, to distinguish it from incandescence or heat-generating light. Life forms could not produce incandescent light without being burned. Their light is produced in chemicals combining in such a way that little or no measurable heat is produced, and the life forms generating it are unharmed. Although bioluminescence is a relatively complicated process, it can be reduced to simple terms. Living light occurs when luciferin and oxygen combine in the presence of luciferase. In a few cases, fireflies the most common, an additional compound called ATP is required.

The earliest recorded experiments with bioluminescence in the late 1800s are attributed to Raphael Dubois, who extracted a luminous fluid from a clam, observing that it continued to glow in the test tube for several minutes. He named the substance luciferin, which means “the bearer of life”. In further research, Dubois discovered that several chemicals were required for bioluminescence to occur. In his notes, it was recorded that a second important substance, which he called luciferase, was always present. In later study of small, luminous sea creatures, Newton Harley concluded that luciferin was composed of carbon, hydrogen, and oxygen, which are the building blocks of all living cells. He also proved that there are a variety of luciferin and luciferase, specific to the plants and animals that produce them.

Much remains unknown, but many scientists who are studying bioluminescence now believe that the origin of the phenomenon may be traced to a time when there was no oxygen in the Earth’s atmosphere. When oxygen was gradually introduced to the atmosphere, it was actually poisonous to life forms, plants and animals produced light to use up the oxygen in a gradual but necessary adaptation. It is speculated that millions of years ago, all life may have produced light to survive. As the millennia passed, life forms on Earth became tolerant of, and finally dependent on oxygen, and the adaptation that produced bioluminescence was no longer necessary, but some primitive plants and animals continued to use the light for new functions such as mating or attracting prey.

Question 41: Bioluminescence is described as all of the following EXCEPT ______.

A. a complex chemicals process

B. an adaptation of early plants and animals to the environment

C. a form of cold light

D. a poisonous substance

1
16 tháng 11 2018

Đáp án D

Dịch nghĩa: Sự phát quang sinh học được miêu tả như tất cả những điều sau NGOẠI TRỮ _______.

A. một quá trình hóa học phức tạp

B. một sự thích ứng của những loài động thực vật tiền sử với môi trường

C. một dạng ánh sáng lạnh

D. một chất có độc

Giải thích: Ta thấy các đáp án còn lại đều được nói đến như những đặc tính của sự phát quang sinh học:

A. Đoạn 1: “Although bioluminescence is a relatively complicated process, it can be reduced to simple terms” - “Mặc dù sự phát quang sinh học là một quá trình tương đối phức tạp, nó có thể được giảm xuống đến những khái niệm đơn giản.”

B. Đoạn cuối: “It is speculated that millions of years ago, all life may have produced light to survive” - “Người ta đoán rằng hàng triệu năm về trước, toàn bộ sự sống có thể đã phải tạo ra ánh sáng để sinh tồn.”

C. Câu đầu bài viết: “Light from a living plant or animal is called bioluminescence, or cold light...” - “Ánh sáng từ một loài động vật hay thực vật còn sống được gọi là sự phát quang sinh học, hay ánh sáng lạnh. . .”

Read the following passage and mark the letter A, B, C or D to indicate the correct answer to each of the questions from 36 to 42. Light from a living plant or animal is called bioluminescence, or cold light, to distinguish it from incandescence or heat-generating light. Life forms could not produce incandescent light without being burned. Their light is produced in chemicals combining in such a way that little or no measurable heat is produced, and the life forms generating it are unharmed....
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 36 to 42.

Light from a living plant or animal is called bioluminescence, or cold light, to distinguish it from incandescence or heat-generating light. Life forms could not produce incandescent light without being burned. Their light is produced in chemicals combining in such a way that little or no measurable heat is produced, and the life forms generating it are unharmed. Although bioluminescence is a relatively complicated process, it can be reduced to simple terms. Living light occurs when luciferin and oxygen combine in the presence of luciferase. In a few cases, fireflies the most common, an additional compound called ATP is required.

The earliest recorded experiments with bioluminescence in the late 1800s are attributed to Raphael Dubois, who extracted a luminous fluid from a clam, observing that it continued to glow in the test tube for several minutes. He named the substance luciferin, which means “the bearer of life”. In further research, Dubois discovered that several chemicals were required for bioluminescence to occur. In his notes, it was recorded that a second important substance, which he called luciferase, was always present. In later study of small, luminous sea creatures, Newton Harley concluded that luciferin was composed of carbon, hydrogen, and oxygen, which are the building blocks of all living cells. He also proved that there are a variety of luciferin and luciferase, specific to the plants and animals that produce them.

Much remains unknown, but many scientists who are studying bioluminescence now believe that the origin of the phenomenon may be traced to a time when there was no oxygen in the Earth’s atmosphere. When oxygen was gradually introduced to the atmosphere, it was actually poisonous to life forms, plants and animals produced light to use up the oxygen in a gradual but necessary adaptation. It is speculated that millions of years ago, all life may have produced light to survive. As the millennia passed, life forms on Earth became tolerant of, and finally dependent on oxygen, and the adaptation that produced bioluminescence was no longer necessary, but some primitive plants and animals continued to use the light for new functions such as mating or attracting prey.

Question 36: Which of the following is the main topic of the passage?

A. Cold light

B. Luciferase

C. Primitive plants and animals

D. Earth’s atmosphere

1
22 tháng 2 2019

Đáp án A

Dịch nghĩa: Chủ đề chính của bài viết là gì?

A. Ánh sáng lạnh

B. Luciferase

C. Thực vật và động vật nguyên thủy

D. Khi hậu trên trái đất

Giải thích: Ta thấy đoạn văn chủ yếu nói về bioluminescence (sự phát quang sinh học) hay còn gọi là cold light (ánh sáng lạnh)