在制作洋葱表皮细胞临时装片时，正确的做法是[]A．尽量将材料撕得薄B．将盖玻片垂直于载玻片后迅速放下C．如有气泡，则用手轻压赶出D．盖上盖玻片后，可直接将稀碘液滴在盖玻片上-七年级生物

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• 制作洋葱表皮细胞临时装片的正确顺序是[]A．撕取内表皮、滴清水、染色、盖盖玻片B．撕取内表皮、滴清水、放置材料、盖盖玻片、染色C．滴清水、撕取内表皮、放置材料、染色、盖盖-七年级生物
• 菠菜放在开水里煮过后水的颜色变绿，而放在冷水中则不产生这种现象，原因是[]A．煮过后，绿色从细胞壁上褪了下来B．叶绿素溶解于热水而不溶解于冷水C．细胞质受热后产生绿色D．细-七年级生物
• 植物细胞既可以________，也可以________，这主要取决于细胞________水溶液的浓度和________浓度的大小。当周围水溶液的浓度________细胞液浓度时，细胞就失水；当细胞液浓
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• 下图是菠菜叶肉细胞的模式图。当我们研磨菠菜叶时，会发现有许多绿色的汁液流出。这些汁液主要来自图中的[]A．1B．3C．5D．6-八年级生物
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• 在显微镜下观察用碘液染色的洋葱表皮细胞时，细胞染色最深的结构是[]A．细胞壁B．细胞膜C．细胞核D．细胞质-七年级生物
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• 下图是植物细胞与动物细胞示意图，请据图作答：（1）植物细胞示意图是_____图，你的判断依据是该细胞有___________。（任写一项）（2）图中②④⑥是动植物细胞都有的结构，其中④的名称-七年级生
• 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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