Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each...

LQ

Lê Quỳnh Anh

2 tháng 5 2017

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. Pollution is a threat to many species on Earth, but sometimes it can cause species to thrive. Such is the case with Pfiesteria piscicida. A one-celled creature called a dinoflagellate, Pfiesteria inhabits warm coastal areas and river mouths, especially along the eastern United States. Although scientists have found evidence of Pfiesteria in 3,000-year-old...

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.

Pollution is a threat to many species on Earth, but sometimes it can cause species to thrive. Such is the case with Pfiesteria piscicida. A one-celled creature called a dinoflagellate, Pfiesteria inhabits warm coastal areas and river mouths, especially along the eastern United States. Although scientists have found evidence of Pfiesteria in 3,000-year-old sea floor sediments and dinoflagellates are thought to be one of the oldest life forms on earth, few people took notice of Pfiesteria.

Lately, however, blooms – or huge, dense populations – of Pfiesteria are appearing in coastal waters, and in such large concentrations the dinoflagellates become ruthless killers. The blooms emit powerful toxins that weaken and entrap fish that swim into the area. The toxins eventually cause the fish to develop large bleeding sores through which the tiny creatures attack, feasting on blood and flesh. Often the damage is astounding. During a 1991 fish kill, which was blamed on Pfiesteria on North Carolina’s Neuse River, nearly one billion fish died and bulldozers had to be brought in to clear the remains from the river. Of course, such events can have a devastating effect on commercially important fish, but that is just one way that Pfiesteria causes problems. The toxins it emits affect human skin in much the same way as they affect fish skin. Additionally, fisherman and others who have spent time near Pfiesteria blooms report that the toxins seem to get into the air, where once inhaled they affect the nervous system, causing severe headaches, blurred vision, nausea, breathing difficulty, short-term memory loss and even cognitive impairment.

For a while, it seemed that deadly Pfiesteria blooms were a threat only to North Carolina waters, but the problem seems to be spreading. More and more, conditions along the east coast seem to be favorable for Pfiesteria. Researchers suspect that pollutants such as animal waste from livestock operations, fertilizers washed from farmlands and waste water from mining operations have probably all combined to promote the growth of Pfiesteria in coastal waters.
Question:What is especially worrying about Pfiesteria blooms?

A. Conditions are becoming increasingly favourable for their spread

B. They are fatal to humans who come in contact with them

C. They have devastated the fishing industry in U.S coastal waters

D. Researchers have no idea as to exactly what causes them

#Mẫu giáo

1

DH

Dương Hoàn Anh

2 tháng 5 2017

Đáp án A

Kiến thức: đọc hiểu

Giải thích:

Điều gì đặc biệt đáng lo ngại về sự nảy nở của Pfiesteria?

A. Các điều kiện ngày càng trở nên thuận lợi cho sự lây lan của chúng

B. Chúng gây tử vong cho người tiếp xúc với chúng

C. Chúng phá hủy ngành công nghiệp đánh cá ở vùng nước ven biển của Mỹ

D. Các nhà nghiên cứu không biết chính xác nguyên nhân tạo ra của chúng

Dẫn chứng: Lately, however, blooms – or huge, dense populations – of Pfiesteria are appearing in coastal waters, and in such large concentrations the dinoflagellates become ruthless killers… More and more, conditions along the east coast seem to be favorable for Pfiesteria.

Đúng(0)

LQ

Lê Quỳnh Anh

21 tháng 4 2017

Read the following passage and mark the letter A, B, C or B on your answer sheet to indicate the correct answer to each of the questions from 30 to 37. Pollution is a threat to many species on Earth, but sometimes it can cause species to thrive. Such is the case with Pfiesteria piscicida. A one-celled creature called a dinoflagellate, Pfiesteria inhabits warm coastal areas and river mouths, especially along the eastern United States. Although scientists have found evidence of Pfiesteria in...

Đọc tiếp

Read the following passage and mark the letter A, B, C or B on your answer sheet to indicate the correct answer to each of the questions from 30 to 37.

Pollution is a threat to many species on Earth, but sometimes it can cause species to thrive. Such is the case with Pfiesteria piscicida. A one-celled creature called a dinoflagellate, Pfiesteria inhabits warm coastal areas and river mouths, especially along the eastern United States. Although scientists have found evidence of Pfiesteria in 3,000-year-old sea floor sediments and dinoflagellates are thought to be one of the oldest life forms on earth, few people took notice of Pfiesteria.

Lately, however, blooms – or huge, dense populations – of Pfiesteria are appearing in coastal waters, and in such large concentrations the dinoflagellates become ruthless killers. The blooms emit powerful toxins that weaken and entrap fish that swim into the area. The toxins eventually cause the fish to develop large bleeding sores through which the tiny creatures attack, feasting on blood and flesh. Often the damage is astounding. During a 1991 fish kill, which was blamed on Pfiesteria on North Carolina’s Neuse River, nearly one billion fish died and bulldozers had to be brought in to clear the remains from the river. Of course, such events can have a devastating effect on commercially important fish, but that is just one way that Pfiesteria causes problems. The toxins it emits affect human skin in much the same way as they affect fish skin. Additionally, fisherman and others who have spent time near Pfiesteria blooms report that the toxins seem to get into the air, where once inhaled they affect the nervous system, causing severe headaches, blurred vision, nausea, breathing difficulty, short-term memory loss and even cognitive impairment.

For a while, it seemed that deadly Pfiesteria blooms were a threat only to North Carolina waters, but the problem seems to be spreading. More and more, conditions along the east coast seem to be favorable for Pfiesteria. Researchers suspect that pollutants such as animal waste from livestock operations, fertilizers washed from farmlands and waste water from mining operations have probably all combined to promote the growth of Pfiesteria in coastal waters.

What is especially worrying about Pfiesteria blooms?

A. Conditions are becoming increasingly favourable for their spread

B. They are fatal to humans who come in contact with them

C. They have devastated the fishing industry in u.s coastal waters

D. Researchers have no idea as to exactly what causes them

#Mẫu giáo

1

DH

Dương Hoàn Anh

21 tháng 4 2017

Đáp án A

Điều gì đặc biệt đáng lo ngại về sự nảy nở của Pfiesteria?

A. Các điều kiện ngày càng trở nên thuận lợi cho sự lây lan của chúng

B. Chúng gây tử vong cho người tiếp xúc với chúng

C. Chúng phá hủy ngành công nghiệp đánh cá ở vùng nước ven biển của Mỹ

D. Các nhà nghiên cứu không biết chính xác nguyên nhân tạo ra của chúng

Dẫn chứng: Lately, however, blooms – or huge, dense populations – of Pfiesteria are appearing in coastal waters, and in such large concentrations the dinoflagellates become ruthless killers… More and more, conditions along the east coast seem to be favorable for Pfiesteria.

Đúng(0)

LQ

Lê Quỳnh Anh

16 tháng 2 2018

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. Pollution is a threat to many species on Earth, but sometimes it can cause species to thrive. Such is the case with Pfiesteria piscicida. A one-celled creature called a dinoflagellate, Pfiesteria inhabits warm coastal areas and river mouths, especially along the eastern United States. Although scientists have found evidence of Pfiesteria in 3,000-year-old...

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.

Pollution is a threat to many species on Earth, but sometimes it can cause species to thrive. Such is the case with Pfiesteria piscicida. A one-celled creature called a dinoflagellate, Pfiesteria inhabits warm coastal areas and river mouths, especially along the eastern United States. Although scientists have found evidence of Pfiesteria in 3,000-year-old sea floor sediments and dinoflagellates are thought to be one of the oldest life forms on earth, few people took notice of Pfiesteria.

Lately, however, blooms – or huge, dense populations – of Pfiesteria are appearing in coastal waters, and in such large concentrations the dinoflagellates become ruthless killers. The blooms emit powerful toxins that weaken and entrap fish that swim into the area. The toxins eventually cause the fish to develop large bleeding sores through which the tiny creatures attack, feasting on blood and flesh. Often the damage is astounding. During a 1991 fish kill, which was blamed on Pfiesteria on North Carolina’s Neuse River, nearly one billion fish died and bulldozers had to be brought in to clear the remains from the river. Of course, such events can have a devastating effect on commercially important fish, but that is just one way that Pfiesteria causes problems. The toxins it emits affect human skin in much the same way as they affect fish skin. Additionally, fisherman and others who have spent time near Pfiesteria blooms report that the toxins seem to get into the air, where once inhaled they affect the nervous system, causing severe headaches, blurred vision, nausea, breathing difficulty, short-term memory loss and even cognitive impairment.

For a while, it seemed that deadly Pfiesteria blooms were a threat only to North Carolina waters, but the problem seems to be spreading. More and more, conditions along the east coast seem to be favorable for Pfiesteria. Researchers suspect that pollutants such as animal waste from livestock operations, fertilizers washed from farmlands and waste water from mining operations have probably all combined to promote the growth of Pfiesteria in coastal waters.
Question:All of the following are true, according to the passage, EXCEPT _____

A. Pfiesteria caused the death of about one billion fish in the late 1990s

B. animal and chemical waste from farmlands, livestock and mining operations may contribute to the expansion of Pfiesteria

C. Pfiesteria was not commonly noticed despite scientific findings

D. the toxic subtances emitted by Pfiesteria have a similar effect on human and fish skins

#Mẫu giáo

1

DH

Dương Hoàn Anh

16 tháng 2 2018

Đáp án A

Giải thích:

Tất cả những điều dưới đây là đúng, theo đoạn văn, ngoại trừ :

A. Pfiesteria gây ra cái chết của khoảng một tỷ cá vào cuối những năm 1990

B. Chất thải động vật và hóa chất từ đất nông nghiệp, chăn nuôi và hoạt động khai thác mỏ có thể góp phần mở rộng Pfiesteria

C. Pfiesteria thường không được chú ý mặc dù có những phát hiện khoa học

D. các chất độc hại phát ra bởi Pfiesteria có tác động tương tự trên da người và cá

Dẫn chứng: During a 1991 fish kill, which was blamed on Pfiesteria on North Carolina’s Neuse River, nearly one billion fish died

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LQ

Lê Quỳnh Anh

29 tháng 8 2019

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. Pollution is a threat to many species on Earth, but sometimes it can cause species to thrive. Such is the case with Pfiesteria piscicida. A one-celled creature called a dinoflagellate, Pfiesteria inhabits warm coastal areas and river mouths, especially along the eastern United States. Although scientists have found evidence of Pfiesteria in 3,000-year-old...

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.

Pollution is a threat to many species on Earth, but sometimes it can cause species to thrive. Such is the case with Pfiesteria piscicida. A one-celled creature called a dinoflagellate, Pfiesteria inhabits warm coastal areas and river mouths, especially along the eastern United States. Although scientists have found evidence of Pfiesteria in 3,000-year-old sea floor sediments and dinoflagellates are thought to be one of the oldest life forms on earth, few people took notice of Pfiesteria.

Lately, however, blooms – or huge, dense populations – of Pfiesteria are appearing in coastal waters, and in such large concentrations the dinoflagellates become ruthless killers. The blooms emit powerful toxins that weaken and entrap fish that swim into the area. The toxins eventually cause the fish to develop large bleeding sores through which the tiny creatures attack, feasting on blood and flesh. Often the damage is astounding. During a 1991 fish kill, which was blamed on Pfiesteria on North Carolina’s Neuse River, nearly one billion fish died and bulldozers had to be brought in to clear the remains from the river. Of course, such events can have a devastating effect on commercially important fish, but that is just one way that Pfiesteria causes problems. The toxins it emits affect human skin in much the same way as they affect fish skin. Additionally, fisherman and others who have spent time near Pfiesteria blooms report that the toxins seem to get into the air, where once inhaled they affect the nervous system, causing severe headaches, blurred vision, nausea, breathing difficulty, short-term memory loss and even cognitive impairment.

For a while, it seemed that deadly Pfiesteria blooms were a threat only to North Carolina waters, but the problem seems to be spreading. More and more, conditions along the east coast seem to be favorable for Pfiesteria. Researchers suspect that pollutants such as animal waste from livestock operations, fertilizers washed from farmlands and waste water from mining operations have probably all combined to promote the growth of Pfiesteria in coastal waters.
Question:In which environment would you NOT expect a Pfiesteria bloom to develop?

A. a marsh which absorbs waste water from a nearby pig farm

B. a river located near a rock quarry

C. a cool mountain lake teeming with fish

D. a river that flows through rich farmland

#Mẫu giáo

1

DH

Dương Hoàn Anh

29 tháng 8 2019

Đáp án C

Kiến thức: đọc hiểu

Giải thích:

Trong môi trường nào mà bạn KHÔNG mong đợi sự phát triển của Pfiesteria?

A. một đầm lầy hút nước thải từ một trại nuôi lợn gần đó

B. một dòng sông gần mỏ đá

C. một hồ trên dãy núi mát mẻ có đầy cá

D. một dòng sông chảy qua vùng đất nông nghiệp phong phú

Dẫn chứng: Pfiesteria inhabits warm coastal areas and river mouths

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LQ

Lê Quỳnh Anh

20 tháng 4 2018

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. Pollution is a threat to many species on Earth, but sometimes it can cause species to thrive. Such is the case with Pfiesteria piscicida. A one-celled creature called a dinoflagellate, Pfiesteria inhabits warm coastal areas and river mouths, especially along the eastern United States. Although scientists have found evidence of Pfiesteria in 3,000-year-old...

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.

Pollution is a threat to many species on Earth, but sometimes it can cause species to thrive. Such is the case with Pfiesteria piscicida. A one-celled creature called a dinoflagellate, Pfiesteria inhabits warm coastal areas and river mouths, especially along the eastern United States. Although scientists have found evidence of Pfiesteria in 3,000-year-old sea floor sediments and dinoflagellates are thought to be one of the oldest life forms on earth, few people took notice of Pfiesteria.

Lately, however, blooms – or huge, dense populations – of Pfiesteria are appearing in coastal waters, and in such large concentrations the dinoflagellates become ruthless killers. The blooms emit powerful toxins that weaken and entrap fish that swim into the area. The toxins eventually cause the fish to develop large bleeding sores through which the tiny creatures attack, feasting on blood and flesh. Often the damage is astounding. During a 1991 fish kill, which was blamed on Pfiesteria on North Carolina’s Neuse River, nearly one billion fish died and bulldozers had to be brought in to clear the remains from the river. Of course, such events can have a devastating effect on commercially important fish, but that is just one way that Pfiesteria causes problems. The toxins it emits affect human skin in much the same way as they affect fish skin. Additionally, fisherman and others who have spent time near Pfiesteria blooms report that the toxins seem to get into the air, where once inhaled they affect the nervous system, causing severe headaches, blurred vision, nausea, breathing difficulty, short-term memory loss and even cognitive impairment.

For a while, it seemed that deadly Pfiesteria blooms were a threat only to North Carolina waters, but the problem seems to be spreading. More and more, conditions along the east coast seem to be favorable for Pfiesteria. Researchers suspect that pollutants such as animal waste from livestock operations, fertilizers washed from farmlands and waste water from mining operations have probably all combined to promote the growth of Pfiesteria in coastal waters.
Question:The word “astounding” in the passage is closest in meaning to _______.

A. continual

B. incredible

C. spectacular

D. apprehensive

#Mẫu giáo

1

DH

Dương Hoàn Anh

20 tháng 4 2018

Đáp án B

Kiến thức: đọc hiểu

Giải thích:

Từ “astounding” trong đoạn văn gần nghĩa nhất với từ nào?

A. tiếp diễn B. khó tin C. ngoạn mục D. sợ hãi

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LQ

Lê Quỳnh Anh

3 tháng 5 2017

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. Pollution is a threat to many species on Earth, but sometimes it can cause species to thrive. Such is the case with Pfiesteria piscicida. A one-celled creature called a dinoflagellate, Pfiesteria inhabits warm coastal areas and river mouths, especially along the eastern United States. Although scientists have found evidence of Pfiesteria in 3,000-year-old...

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.

Pollution is a threat to many species on Earth, but sometimes it can cause species to thrive. Such is the case with Pfiesteria piscicida. A one-celled creature called a dinoflagellate, Pfiesteria inhabits warm coastal areas and river mouths, especially along the eastern United States. Although scientists have found evidence of Pfiesteria in 3,000-year-old sea floor sediments and dinoflagellates are thought to be one of the oldest life forms on earth, few people took notice of Pfiesteria.

Lately, however, blooms – or huge, dense populations – of Pfiesteria are appearing in coastal waters, and in such large concentrations the dinoflagellates become ruthless killers. The blooms emit powerful toxins that weaken and entrap fish that swim into the area. The toxins eventually cause the fish to develop large bleeding sores through which the tiny creatures attack, feasting on blood and flesh. Often the damage is astounding. During a 1991 fish kill, which was blamed on Pfiesteria on North Carolina’s Neuse River, nearly one billion fish died and bulldozers had to be brought in to clear the remains from the river. Of course, such events can have a devastating effect on commercially important fish, but that is just one way that Pfiesteria causes problems. The toxins it emits affect human skin in much the same way as they affect fish skin. Additionally, fisherman and others who have spent time near Pfiesteria blooms report that the toxins seem to get into the air, where once inhaled they affect the nervous system, causing severe headaches, blurred vision, nausea, breathing difficulty, short-term memory loss and even cognitive impairment.

For a while, it seemed that deadly Pfiesteria blooms were a threat only to North Carolina waters, but the problem seems to be spreading. More and more, conditions along the east coast seem to be favorable for Pfiesteria. Researchers suspect that pollutants such as animal waste from livestock operations, fertilizers washed from farmlands and waste water from mining operations have probably all combined to promote the growth of Pfiesteria in coastal waters.
Question: What is true of Pfiesteria?

A. It seems to flourish in the presence of certain pollutants

B. It has been a menace to fish and humans for over 3000 years

C. It is the oldest life form on earth

D. In large concentrations, it poses a threat to fish but not to humans

#Mẫu giáo

1

DH

Dương Hoàn Anh

3 tháng 5 2017

Đáp án A

Kiến thức: đọc hiểu

Giải thích:

Điều gì đúng về Pfiesteria?

A. Nó dường như phát triển trong sự hiện diện của các chất ô nhiễm nhất định

B. Nó là mối nguy hại đối với cá và người trong hơn 3000 năm

C. Nó là dạng sống lâu nhất trên trái đất

D. Ở mức độ lớn, nó gây ra mối đe dọa đối với cá nhưng không phải đối với con người

Dẫn chứng: Pollution is a threat to many species on Earth, but sometimes it can cause species to thrive. Such is the case with Pfiesteria piscicida.

Đúng(0)

LQ

Lê Quỳnh Anh

6 tháng 12 2019

Read the following passage and mark the letter A, B, C or B on your answer sheet to indicate the correct answer to each of the questions from 30 to 37. Pollution is a threat to many species on Earth, but sometimes it can cause species to thrive. Such is the case with Pfiesteria piscicida. A one-celled creature called a dinoflagellate, Pfiesteria inhabits warm coastal areas and river mouths, especially along the eastern United States. Although scientists have found evidence of Pfiesteria in...

Đọc tiếp

Read the following passage and mark the letter A, B, C or B on your answer sheet to indicate the correct answer to each of the questions from 30 to 37.

Pollution is a threat to many species on Earth, but sometimes it can cause species to thrive. Such is the case with Pfiesteria piscicida. A one-celled creature called a dinoflagellate, Pfiesteria inhabits warm coastal areas and river mouths, especially along the eastern United States. Although scientists have found evidence of Pfiesteria in 3,000-year-old sea floor sediments and dinoflagellates are thought to be one of the oldest life forms on earth, few people took notice of Pfiesteria.

Lately, however, blooms – or huge, dense populations – of Pfiesteria are appearing in coastal waters, and in such large concentrations the dinoflagellates become ruthless killers. The blooms emit powerful toxins that weaken and entrap fish that swim into the area. The toxins eventually cause the fish to develop large bleeding sores through which the tiny creatures attack, feasting on blood and flesh. Often the damage is astounding. During a 1991 fish kill, which was blamed on Pfiesteria on North Carolina’s Neuse River, nearly one billion fish died and bulldozers had to be brought in to clear the remains from the river. Of course, such events can have a devastating effect on commercially important fish, but that is just one way that Pfiesteria causes problems. The toxins it emits affect human skin in much the same way as they affect fish skin. Additionally, fisherman and others who have spent time near Pfiesteria blooms report that the toxins seem to get into the air, where once inhaled they affect the nervous system, causing severe headaches, blurred vision, nausea, breathing difficulty, short-term memory loss and even cognitive impairment.

For a while, it seemed that deadly Pfiesteria blooms were a threat only to North Carolina waters, but the problem seems to be spreading. More and more, conditions along the east coast seem to be favorable for Pfiesteria. Researchers suspect that pollutants such as animal waste from livestock operations, fertilizers washed from farmlands and waste water from mining operations have probably all combined to promote the growth of Pfiesteria in coastal waters.

What is true of Pfiesteria?

A. It seems to flourish in the presence of certain pollutants

B. It has been a menace to fish and humans for over 3000 years.

C. It is the oldest life form on earth

D. In large concentrations, it poses a threat to fish but not to humans.

#Mẫu giáo

1

DH

Dương Hoàn Anh

6 tháng 12 2019

Đáp án A

Điều gì đúng về Pfiesteria?

A. Nó dường như phát triển trong sự hiện diện của các chất ô nhiễm nhất định

B. Nó là mối nguy hại đối với cá và người trong hơn 3000 năm

C. Nó là dạng sống lâu nhất trên trái đất

D. Ở mức độ lớn, nó gây ra mối đe dọa đối với cá nhưng không phải đối với con người

Dẫn chứng: Pollution is a threat to many species on Earth, but sometimes it can cause species to thrive. Such is the case with Pfiesteria piscicida.

Đúng(0)

LQ

Lê Quỳnh Anh

30 tháng 10 2018

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. Pollution is a threat to many species on Earth, but sometimes it can cause species to thrive. Such is the case with Pfiesteria piscicida. A one-celled creature called a dinoflagellate, Pfiesteria inhabits warm coastal areas and river mouths, especially along the eastern United States. Although scientists have found evidence of Pfiesteria in 3,000-year-old...

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.

Pollution is a threat to many species on Earth, but sometimes it can cause species to thrive. Such is the case with Pfiesteria piscicida. A one-celled creature called a dinoflagellate, Pfiesteria inhabits warm coastal areas and river mouths, especially along the eastern United States. Although scientists have found evidence of Pfiesteria in 3,000-year-old sea floor sediments and dinoflagellates are thought to be one of the oldest life forms on earth, few people took notice of Pfiesteria.

Lately, however, blooms – or huge, dense populations – of Pfiesteria are appearing in coastal waters, and in such large concentrations the dinoflagellates become ruthless killers. The blooms emit powerful toxins that weaken and entrap fish that swim into the area. The toxins eventually cause the fish to develop large bleeding sores through which the tiny creatures attack, feasting on blood and flesh. Often the damage is astounding. During a 1991 fish kill, which was blamed on Pfiesteria on North Carolina’s Neuse River, nearly one billion fish died and bulldozers had to be brought in to clear the remains from the river. Of course, such events can have a devastating effect on commercially important fish, but that is just one way that Pfiesteria causes problems. The toxins it emits affect human skin in much the same way as they affect fish skin. Additionally, fisherman and others who have spent time near Pfiesteria blooms report that the toxins seem to get into the air, where once inhaled they affect the nervous system, causing severe headaches, blurred vision, nausea, breathing difficulty, short-term memory loss and even cognitive impairment.

For a while, it seemed that deadly Pfiesteria blooms were a threat only to North Carolina waters, but the problem seems to be spreading. More and more, conditions along the east coast seem to be favorable for Pfiesteria. Researchers suspect that pollutants such as animal waste from livestock operations, fertilizers washed from farmlands and waste water from mining operations have probably all combined to promote the growth of Pfiesteria in coastal waters.
Question:What were bulldozers used for in the Neuse River?

A. cleaning up the sediment at the bottom of the river

B. excavating holes to bury the dead fish

C. scooping up the vast number of dead fish in the water

D. removing the huge amount of Pfiesteria from the river

#Mẫu giáo

1

DH

Dương Hoàn Anh

30 tháng 10 2018

Đáp án C

Kiến thức: đọc hiểu

Giải thích:

Xe ủi đất được sử dụng trong sông Neuse để làm gì?

A. làm sạch trầm tích ở đáy sông

B. đào hố để chôn các con cá chết

C. nhặt được một lượng lớn cá chết trong nước

D. loại bỏ lượng Pfiesteria khổng lồ từ dòng sông

Dẫn chứng: During a 1991 fish kill, which was blamed on Pfiesteria on North Carolina’s Neuse River, nearly one billion fish died and bulldozers had to be brought in to clear the remains from the river.

Đúng(0)

LQ

Lê Quỳnh Anh

16 tháng 7 2019

Read the following passage and mark the letter A, B, C or B on your answer sheet to indicate the correct answer to each of the questions from 30 to 37. Pollution is a threat to many species on Earth, but sometimes it can cause species to thrive. Such is the case with Pfiesteria piscicida. A one-celled creature called a dinoflagellate, Pfiesteria inhabits warm coastal areas and river mouths, especially along the eastern United States. Although scientists have found evidence of Pfiesteria in...

Đọc tiếp

Read the following passage and mark the letter A, B, C or B on your answer sheet to indicate the correct answer to each of the questions from 30 to 37.

Pollution is a threat to many species on Earth, but sometimes it can cause species to thrive. Such is the case with Pfiesteria piscicida. A one-celled creature called a dinoflagellate, Pfiesteria inhabits warm coastal areas and river mouths, especially along the eastern United States. Although scientists have found evidence of Pfiesteria in 3,000-year-old sea floor sediments and dinoflagellates are thought to be one of the oldest life forms on earth, few people took notice of Pfiesteria.

Lately, however, blooms – or huge, dense populations – of Pfiesteria are appearing in coastal waters, and in such large concentrations the dinoflagellates become ruthless killers. The blooms emit powerful toxins that weaken and entrap fish that swim into the area. The toxins eventually cause the fish to develop large bleeding sores through which the tiny creatures attack, feasting on blood and flesh. Often the damage is astounding. During a 1991 fish kill, which was blamed on Pfiesteria on North Carolina’s Neuse River, nearly one billion fish died and bulldozers had to be brought in to clear the remains from the river. Of course, such events can have a devastating effect on commercially important fish, but that is just one way that Pfiesteria causes problems. The toxins it emits affect human skin in much the same way as they affect fish skin. Additionally, fisherman and others who have spent time near Pfiesteria blooms report that the toxins seem to get into the air, where once inhaled they affect the nervous system, causing severe headaches, blurred vision, nausea, breathing difficulty, short-term memory loss and even cognitive impairment.

For a while, it seemed that deadly Pfiesteria blooms were a threat only to North Carolina waters, but the problem seems to be spreading. More and more, conditions along the east coast seem to be favorable for Pfiesteria. Researchers suspect that pollutants such as animal waste from livestock operations, fertilizers washed from farmlands and waste water from mining operations have probably all combined to promote the growth of Pfiesteria in coastal waters.

What is the main function of the toxins emitted by the dinoflagellates?

A. They are quick-acting poisons that kill fish within minutes.

B. They weaken the fish just long enough for the tiny creatures to attack

C. They damage the nervous system of potential predators.

D. They cause fish to develop wounds on which creatures feed.

#Mẫu giáo

1

DH

Dương Hoàn Anh

16 tháng 7 2019

Đáp án B

Chức năng chính của các chất độc được phát ra bởi các chất tẩy rửa dinoflagellates là gì?

A. Chúng là chất độc nhanh chóng giết chết cá trong vòng vài phút.

B. Chúng làm suy yếu cá đủ dài để các sinh vật nhỏ xíu tấn công

C. Chúng phá hủy hệ thần kinh của những kẻ thù tiềm tàng.

D. Chúng làm cho cá phát triển vết thương các sinh vật gây nên

Dẫn chứng: The toxins eventually cause the fish to develop large bleeding sores through which the tiny creatures attack, feasting on blood and flesh.

Dịch bài đọc:

Ô nhiễm là mối đe dọa tới nhiều loài trên trái đất, nhưng đôi khi nó có thể khiến một số loài phát triển mạnh mẽ. Tiêu biểu là Pfiesteria piscicida. Là một loài sinh vật đơn bào có tên gọi tảo hai roi, Pfiesteria sinh sống ở các vùng ven biển và cửa sông ấm, đặc biệt là dọc theo vùng đông Mĩ. Tuy các nhà khoa học đã tìm thấy bằng chứng về Pfiesteria trong những tràm tích 3000 năm tuổi dưới đáy biển và tảo hại roi được cho là hình thái sinh vật sống lâu đời nhất trên trái đất, ít người chú ý đến Pfiesteria.

Tuy vậy, gần đây, sự kiện “tảo nở hoa” - hay mật độ lớn, dày đặc - của Pfiesteria đang xuất hiện ở các vùng nước ven biển, và ở mức độ tập trung lớn đến mức tảo hai roi trở thành những kẻ sát nhân tàn nhẫn. Những khu vực “tảo nở hoa” thải ra các chất cực độc làm suy yếu và bẫy loài cá bơi vào vùng tảo. Các chất độc dần khiến cho cá phát triển những vết đau rỉ máu qua đó những sinh vật tí hon sẽ tấn công, ăn lấy ăn để máu và thịt của chúng. Thông thường thiệt hại rất đáng kinh ngạc. Năm 1991, một vụ cá chết trên sông Neuse ở bắc Carolina được cho là do Pfiesteria, gần 1 tỉ con cá đã chết và các xe ủi phải huy động đến dọn xác cá trên sông. Tất nhiên, những sự kiện như vậy có thể gây ra sự tàn phá đối với các loài cá có tầm thương mại quan trọng, nhưng đó mới chỉ là một vấn đề tạo bởi Pfiesteria. Các chất độc nó tiết ra gây ảnh hưởng đến da người giống như với da cá. Hơn nữa, ngư dân tiếp xúc lâu ngày với các nơi Pfiesteria “nở hoa” báo lại rằng chất độc dường như đã lan vào không khí, một khi hít phải sẽ ảnh hưởng tới hệ thần kinh, gây đau đầu dữ dội, hoa mắt, nôn mửa, khó thở. mất trí nhớ ngắn hạn và thậm chí là suy giảm nhận thức.

Một thời gian, có vẻ như Pfiesteria chỉ đe dọa các vùng biển ở bắc Carolina, nhưng vấn đề dường như đang lan rộng. Dần dần, điều kiện sống quanh các vùng ven biển phía đông ngày càng thuận lợi cho Pfiesteria. Các nhà nghiên cứu nghi ngờ rằng các chất ô nhiễm từ đất trang trại và nước thải từ các hoạt động khai thác mỏ có thể đã cùng kết hợp xúc tiến cho sự phát triển của Pfiesteria các vùng nước ven biển.

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