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Unformatted text preview: hese fishes prevents them from slowing down.
○The streamlining of these fishes tends to slow down their breathing.
○Opening the mouth to breathe can reduce the speed of these fishes.
8. The word channel in the passage is closest in meaning to ○Reduce
Paragraph 8: There are adaptations that increase the amount of forward thrust as well as those that reduce drag. Again, these fishes are the envy of engineers. Their high, narrow tails with sweptback tips are almost perfectly adapted to provide propulsion with the least possible effort. Perhaps most important of all to these and other fast swimmers is their ability to sense and make use of swirls and eddies (circular currents) in the water. They can glide past eddies that would slow them down and then gain extra thrust by "pushing off" the eddies. Scientists and engineers are beginning to study this ability of fishes in the hope of designing more efficient propulsion systems for ships.
9. According to the passage, one of the adaptations of fastswimming fishes that might be used to improve the performance of ships is these fishes' ability to ○Swim directly through eddies
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○Make efficient use of water currents ○Cover great distances without stopping
○Gain speed by forcing water past their gills
Paragraph 9: The muscles of these fishes and the mechanism that maintains a warm body temperature are also highly efficient. A bluefin tuna in water of 7°C (45°F) can maintain a core temperature of over 25°C (77°F). This warm body temperature may help not only the muscles to work better, but also the brain and the eyes. The billfishes have gone one step further. They have evolved special "heaters" of modified muscle tissue that warm the eyes and brain, maintaining peak performance of these critical organs.
10. According to paragraph 9, which of the following is true of bluefin tunas? ○Their eyes and brain are more efficient than those of any other fish.
○Their body temperature can change greatly depending on the water temperature.
○They can swim in waters that are much colder than their own bodies.
○They have special muscle tissue that warms their eyes and brain.
Paragraph 6: ■Because they are always swimming, tunas simply have to open their mouths and water is forced in and over their gills. ■Accordingly, they have lost most of the muscles that other fishes use to suck in water and push it past the gills. ■In fact, tunas must swim to breathe. ■They must also keep swimming to keep from sinking, since most have largely or completely lost the swim bladder, the gasfilled sac that helps most other fish remain buoyant. 11. Look at the four squares [■l that indicate where the following sentence can be added to the passage. Consequently, tunas do not need to suck in water. Where would the sentence best fit? 12. Directions:...
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This note was uploaded on 09/17/2013 for the course LANGUAGE 13DL208 taught by Professor Wang during the Fall '13 term at East China Normal University.
- Fall '13