大多数两栖动物的生殖方式为[]A．雌雄同体，异体受精，受精必须在陆地上进行B．雌雄同体，异体受精，受精必须在水中完成C．雌雄异体，体外受精，受精必须在陆地上进行D．雌雄异体-八年级生物

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• 两栖动物不能完全适于陆地生活，主要原因是[]A．两栖动物的体温不恒定B．两栖动物的生殖发育离不开水C．两栖动物的心室中有混合血D．两栖动物的肺发育不善-八年级生物
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• 对于蛙、蝾螈等两栖动物的“两栖”，我们可以理解为[]A．皮肤裸露有花纹的动物B．成体既可以在水中生活，也可以在陆地上生活C．幼体在水中发育，成体营水陆两栖D．具有变态发育的动-八年级生物
• 下列行为中，不属于雄蛙为能有大量的后代并且提高后代的存活率而必须在繁殖季节进行的行为是[]A．全力鸣叫B．抱住排卵前的雌蛙C．选择水源充沛、水质良好的场所D．筑巢-八年级生物
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• 请分析回答下列有关青蛙生殖发育及结构功能的问题：（1）在宋朝诗人赵师秀的“黄梅时节家家雨，青草池塘处处蛙”诗句中，“雨”和“蛙”的内在联系有：青蛙的受精方式为___________，发-八年级生物
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• 鸣叫的青蛙是______性的，它的口角边有一对鸣囊。在青蛙抱对的池塘水面，会发现漂浮着的一片片胶状透明物，这是青蛙的卵块，里面有许多________。-八年级生物
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• 对蛙的生殖发育有直接影响的是[]A．空气污染B．噪声污染C．水质污染D．固体废弃物污染-八年级生物
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