Câu hỏi:
26/03/2020 1,168Read 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 that follow.
Under certain circumstances, the human body must cope with gases at greater-than-normal atmospheric pressure. For example, gas pressures increase rapidly during a drive made with scuba gear because the breathing equipment allows divers to stay underwater longer and dive deeper. The pressure exerted on the human body increases by 1 atmosphere for every 10 meters of depth in seawater, so that at 39 meters in seawater a diver is exposed to pressure of about 4 atmospheres. The pressure of the gases being breathed must equal the external pressure applied to the body, otherwise breathing is very difficult. Therefore all of the gases in the air breathed by a scuba diver at 40 meter are present at five times their usual pressure. Nitrogen, which composes 80 percent of the air we breathe, usually causes a balmy feeling of well-being at this pressure. At a depth of 5 atmospheres, nitrogen causes symptoms resembling alcohol intoxication, known as nitrogen narcosis. Nitrogen narcosis apparently results from a direct effect on the brain of the large amounts of nitrogen dissolved in the blood. Deep dives are less dangerous if helium is substituted for nitrogen, because under these pressures helium does not exert a similar narcotic effect.
As a scuba diver descends, the pressure of nitrogen on the lungs increases. Nitrogen then diffuses from the lungs to the blood, and from the blood to body tissues. Nitrogen then diffuses from the lungs to the blood, and from the blood to body tissues The reverse occurs when the diver surfaces, the nitrogen pressure in the lungs falls and the nitrogen diffuses from the tissues into the blood, and from the blood into the lungs. If the return to the surface is too rapid, nitrogen in the tissues and blood cannot diffuse out rapidly enough and nitrogen bubbles are formed. They can cause severe pains, particularly around the joints.
Another complication may result if the breath is held during ascent. During ascent from a depth of 10 meters, the volume of air in the lungs will double because the air pressure at the surface is only half of what it was at 10 meters. This change in volume may cause the lungs to distend and even rupture. This condition is called air embolism.
To avoid this event, a diver must ascend slowly, never at a rate exceeding the rise of the exhaled air bubbles, and must exhale during ascent.
It can be inferred from the passage that which of the following presents the greatest danger to a diver?
Đáp án chính xác
Câu hỏi trong đề:
25 Đề thi thpt quốc gia môn Tiếng Anh có lời giải chi tiết !!
Sách mới 2k7: Tổng ôn Toán, Lí, Hóa, Văn, Sử, Địa…. kỳ thi tốt nghiệp THPT Quốc gia 2025, đánh giá năng lực (chỉ từ 110k).
Quảng cáo
Trả lời:
Giải bởi Vietjack
Chọn C
Có thể suy ra từ bài đọc rằng điều gì là mối nguy hiểm lớn nhất đối với thợ lặn?
A. Pressurized helium: Khí Heli nén
B. Nitrogen diffusion: Sự khuếch tán khí Nitơ
C. An air embolism: Sự thuyên tắc hơi
D. Nitrogen bubbles: Bóng khí Nitơ
Thông tin ở đoạn cuối, dòng thứ nhất. “During ascent from a depth of 10 meters, the volume of air in the lung will double because the air pressure at the surface is only half of what it was at 10 meters. This change in volume may cause the lungs to distend and even rupture. This condition is called air embolism.” (Trong quá trình nồi lên từ độ sâu 10 mét, lượng không khí trong phổi sẽ tăng lên gấp đôi vì áp lực khí tại bề mặt nước chỉ còn 1 nửa so với ở độ sâu 10 mét. Sự thay đổi về lượng khí có thể làm phổi sưng phồng, thậm chí là vỡ nát. Hiện tượng này gọi là thuyên tắc hơi.)
Nhà sách VIETJACK:
CÂU HỎI HOT CÙNG CHỦ ĐỀ
Câu 1:
Mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the following questions.
By the time next summer, you _________ your studies
Xem đáp án »
26/03/2020
71,760
Câu 2:
Mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the following questions.
What are your plans for _________ future?
Xem đáp án »
26/03/2020
41,820
Câu 3:
Mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the following questions.
She looked _________ to see who was going _________ her.
Xem đáp án »
26/03/2020
23,230
Câu 4:
Mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the following questions.
All of the students appreciate the _________ of English learning.
Xem đáp án »
05/06/2024
22,159
Câu 5:
Mark the letter A, B, C or D on your answer sheet to indicate the most suitable response to complete each of the following exchanges.
“Could you get to the park before 3 o’clock?” “ _________ I’m still at the meeting then”
Xem đáp án »
26/03/2020
21,484
Câu 6:
Mark the letter A, B, C or D on your answer sheet to indicate the correct answer to
each of the following questions.
Scientific _________ help to explore some places and discover more and more remote parts of the world.
Xem đáp án »
26/03/2020
15,985
Câu 7:
Mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the following questions.
These new economic reforms have allowed for international _________and development in the country.
Xem đáp án »
26/03/2020
12,929
về câu hỏi!