| The two claws of the mature American
lobster are decidedly different from each other. The crusher claw is short and
stout; the cutter claw is long and slender. Such bilateral asymmetry, in which
the right side of the body is, in all other respects, a mirror image of the left
side, is not unlike handedness in humans. But where the majority of humans are
right-handed, in lobsters the crusher claw appears with equal probability on
either the right side or left side of the body. Bilateral asymmetry of the claws comes about gradually. In the juvenile fourth and fifth stages of development, the paired claws are symmetrical and cutterlike. Asymmetry begins to appear in the juvenile sixth stage of development, and the paired claws further diverge toward well-defined cutter and crusher claws during succeeding stages. An intriguing aspect A. drawing an analogy between asymmetry in lobsters and handed in humans. B. developing a method for predicating whether crusher claws in lobster will appear on the left or right side C. explaining differences between lobsters’ crusher claws and cutter claws D. discussing a possible explanation for the way bilateral asymmetry is determined in lobsters [填空题]Passage Two
At two minutes to noon in September 1 of 1923, the great clock in Tokyo
stopped. (82) Tokyo Bay shook as if huge rug had been pulled from under it. (83)
Towered, above the bay, the 4000-meter Mount Fuji stood above a deep trench in
the sea. (84) It was from this trench where the earthquake came at a
magnitude of 8.3 on the Richter scale.
Huge waves swept over the city. (85) Boats were driven inland, and buildings and people were dragged out sea. (86) The tremors dislodged part of a hillside, which gave way, brushing trains, stations and bodies the wafer below. (87) Three massive shocks wrecked the of Tokyo and Yokohama and, during the next six hours, there were more than 100 aftershocks. The casualties were enormous, but there were also some lucky survivors. (88) The most remarkably was a woman who was having a bath in her room at the Tokyo Grand Hotel. (89) As for the hotel collapsed, sh [单项选择]Passage 2
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