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Text 3Under certain circumstances, the human body must cope with gases at greater-than-normal atmospheric pressure. For example, gas pressures increase rapidly during a dive 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 30 meters in seawater a diver is exposed to a 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 meters are present at five times their usual pressure. Nitrogen, which composes 80 per cent 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 cause under these pressurized helium does not exert a similar narcotic effect.As a scuba diver descends, the pressure of nitrogen in the lungs increases. 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 diver()

A. Pressurized helium.
B. Nitrogen diffusion.
C. Nitrogen bubbles.
D. An air embolism.

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At the beginning of the century, medical scientists made a surprising discovery: that we are (1) not just of flesh and blood but also of time. They were able to (2) that we all have an internal "body clock" which (3) the rise and fall of our body energies, making us different from one day to the (5) . These forces became known as biorhythms: they create the (5) in our everyday life.The (6) of an internal "body clock" should not be too surprising, (7) the lives of most living things are dominated by the 24-hour night-and-day cycle. The most obvious (8) of this cycle is the (9) we feel tired and fall asleep at night and become awake and (10) during the day. (11) the 24-hour rhythm is interrupted, most people experience unpleasant side effects.(12) , international aeroplane travelers often experience "jet lag" when traveling across time (13) . People who are not used to (14) work can find that lack of sleep affects their work performance.(15) the daily rhythm of sleeping and waking, we also have other rhythms which (16) .longer than one day and which influence wide areas of our lives. Most of us would agree that we feel good on (17) days and net so good on others. Sometimes we are (18) fingers and thumbs but on other days we have excellent coordination. There are times when we appear to be accident-prone, or when our temper seems to be on a short fuse. Isn’t it also strange (19) ideas seem to flow on some days but at other times are (20) nonexistent Musicians, painters and writers often talk about "dry spells". Read the following text. Choose the best word(s) for each numbered blank and mark A,B,C or D on ANSWER SHEET Ⅰ.20()

A. last
B. move
C. live
D. survive

Text 2The more women and minorities make their way into the ranks of management, the more they seem to want to talk a bout things formerly judged to be best left unsaid. The newcomers also tend to see office matters with a fresh eye, in the process sometimes coming up with critical analyses of the forces that shape everyone’ s experience in the organization.Consider the novel views of Harvey Coleman of Atlanta on the subject of getting ahead.Coleman is black. He spent 11 years with IBM, half of them working in management department, and now serves as a consultant to the likes of AT & T, Coca Cola, Prudential, and Merch. Coleman says that based on what he’s seen at big companies, he weighs the different elements that make for long term career success as follows: performance counts a mere 10%; image 30%; and exposure, a full 60%.Coleman concludes that excellent job performance is so common these days that while doing your work well may win you pay increases, it won’t secure you the big promotion.He finds that advancement more often depends on how many people know you and your work, and how high up they are. Ridiculous beliefs Not too many people, especially many women and members of minority races who, like Coleman, feel that the scales have dropped from their eyes."Women and blacks in organizations work under false beliefs, "says Kaleel Jamison, a New York based management consultant who helps corporations deal with these issues. "They think that if you work hard, you’ 11 get ahead that someone in authority will reach down and give you a promotion." She added, "Most women and blacks are so frightened that people will think they’ve gotten ahead because of their sex or color that they play down their visibility." Her advice to those folks: learn the ways that white males have traditionally used to find their way into the spotlight. The reason why women and blacks play down their visibility is that they()

A. know that someone in authority will reach down and give them a promotion
B. don't want people to think that their promotions were due to sex or color
C. don't want to give people the impression that they work under false beliefs
D. believe they can get promoted by reason of their sex or color

Most people who travel long distances complain of jetlag (喷气飞行时差反应). Jetlag makes business travelers less productive and more prone (21) making mistakes. It is actually caused by (22) of your "body clock"—a small cluster of brain cells that controls the timing of biological (23) . The body clock is designed for a (24) rhythm of daylight and darkness, so that it is thrown out of balance when it (25) daylight and darkness at the "wrong" times in a new time zone. The (26) of jetlag often persist for days (27) the internal body clock slowly adjusts to the new time zone. Now a new anti-jetlag system is (28) that is based on proven (29) pioneering scientific re- search. Dr. Martin Moore-Ere has (30) a practical strategy to adjust the body clock much sooner to the new time zone (31) controlled exposure to bright light. The time zone shift is easy to accomplish and eliminates (32) of the discomfort of jetlag. A successful time zone shift depends on knowing the exact times to either (33) or avoid bright light. Exposure to light at the wrong time can actually make jetlag worse. The proper schedule (34) light exposure depends a great deal on (35) travel plans. Data on a specific flight itinerary (旅行路线) and the individual’s sleep (36) are used to produce a Trip Guide with (37) on exactly when to be exposed to bright light. When the Trip Guide calls (38) bright light you should spend time outdoors if possible. If it is dark outside, or the weather is bad, (39) you are on an aero plane, you can use a special light device to provide the necessary light (40) for a range of activities such as reading, watching TV or working. 28().

A. devised
B. recognized
C. scrutinized
D. visualized

Most people who travel long distances complain of jetlag (喷气飞行时差反应). Jetlag makes business travelers less productive and more prone (21) making mistakes. It is actually caused by (22) of your "body clock"—a small cluster of brain cells that controls the timing of biological (23) . The body clock is designed for a (24) rhythm of daylight and darkness, so that it is thrown out of balance when it (25) daylight and darkness at the "wrong" times in a new time zone. The (26) of jetlag often persist for days (27) the internal body clock slowly adjusts to the new time zone. Now a new anti-jetlag system is (28) that is based on proven (29) pioneering scientific re- search. Dr. Martin Moore-Ere has (30) a practical strategy to adjust the body clock much sooner to the new time zone (31) controlled exposure to bright light. The time zone shift is easy to accomplish and eliminates (32) of the discomfort of jetlag. A successful time zone shift depends on knowing the exact times to either (33) or avoid bright light. Exposure to light at the wrong time can actually make jetlag worse. The proper schedule (34) light exposure depends a great deal on (35) travel plans. Data on a specific flight itinerary (旅行路线) and the individual’s sleep (36) are used to produce a Trip Guide with (37) on exactly when to be exposed to bright light. When the Trip Guide calls (38) bright light you should spend time outdoors if possible. If it is dark outside, or the weather is bad, (39) you are on an aero plane, you can use a special light device to provide the necessary light (40) for a range of activities such as reading, watching TV or working. 23().

A. norm
B. mode
C. pattern
D. style

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