探究与实践题某同学在做西红柿果肉细胞临时装片时，他发现以下问题，请你帮助他分析、解决一下。(1)在观察的过程中，视野忽明忽暗。________________________(2)他挑取了少量-七年级

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• 制作洋葱鳞片叶表皮细胞的临时装片时，染色的正确方法是[]A．先将碘液滴在载玻片中央，再将洋葱表皮放入并展平B．先盖盖玻片，再将碘液滴在盖玻片一侧，另一侧用吸水纸吸C．将洋-七年级生物
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• 阅读理解。 The kids at the top of the class get there by mastering (掌握) a few good ways that others can l
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• 将名词与相应的功能对应起来。1．循环系统a．保护内部柔嫩部分2．细胞膜b．使光能变成化学能3．叶绿体c．控制物质进出4．上皮组织d．运输体内物质5．分生组织e．运输水和无机盐6．输导组-七年级生物
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• 番茄中带有酸味的物质存在于[]A．细胞核B．细胞质C．液泡D．细胞壁-七年级生物
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