题干

根据所学,分析回答:“黄梅时节家家雨,青草池塘处处蛙”。春末夏处,青蛙“呱、呱、呱”的叫声此起彼伏。如果寻声找去,你会发现池塘中的青蛙正在抱对。不久,如果你再来,会在水中看到小蝌蚪。如果你继续观察下去,你会看到青蛙幼体外形变化的全过程。
(1) 招引雌蛙时雄蛙所作出的反应是 ____ ,便于精子和卵细胞结合,提高受精率时雌雄蛙所作出的反应是 ____ 。 
(2)小蝌蚪外形像一条小鱼,小蝌蚪在水中用____ 进行呼吸。
写出青蛙发育的全过程:____   → ____   → ____ 

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答案(点此获取答案解析)

鸣叫,抱对,鳃,卵,蝌蚪,青蛙

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