【题目】以下是与高中生物实验有关的内容，请回答下列问题：
（1）脂肪的鉴定中，洗去浮色时常用50%的酒精溶液，是因为 。
（2）在“观察DNA和RNA在细胞中的分布”实验中，将口腔上皮细胞置入8%的盐酸溶液中水解的主要目的是 ，有利于DNA与染色剂结合。
（3）比较过氧化氢在不同条件下的分解，实验的因变量是 。
（4）在用琼脂块模拟细胞大小与物质运输关系的实验中，物质运输的效率可以用 来衡量。
（5）生物组织细胞中某些成分的鉴定和结构的观察，需要选取适当的实验材料、试剂和仪器，下列材料、仪器（试剂）与成分鉴定和结构观察匹配不正确的有（ ）（多选）
A．西瓜汁～斐林试剂～检测生物组织中的糖类
B．嫩绿的菠菜叶～层析液～提取光合色素
C．口腔上皮细胞～健那绿染液～观察DNA在细胞中的分布
D．新鲜菠菜叶～高倍显微镜～观察叶绿体
【答案】
（1）苏丹Ⅲ染液或苏丹Ⅳ染液能溶于酒精
（2）使染色质中DNA与蛋白质分离
（3）过氧化氢分解速率（或其他合理答案）
（4）NaOH扩散体积/整个琼脂块的体积
（5）A、B、C
【解析】
（1）在脂肪的鉴定中，洗去浮色时常用体积分数为50%的酒精溶液，因为苏丹Ⅲ染液或苏丹Ⅳ染液能溶于酒精。
（2）在“观察DNA和RNA在细胞中的分布”实验中，将口腔上皮细胞置入8%的盐酸溶液中水解的主要目的是使染色质中的DNA与蛋白质分离，有利于DNA与染色剂结合。
（3）比较过氧化氢在不同条件下的分解，实验的因变量是过氧化氢分解速率。
（4）在用琼脂块模拟细胞大小与物质运输关系的实验中，物质运输的效率可以用NaOH扩散体积/整个琼脂块的体积来衡量。
（5）检测生物组织中的还原糖，不用西瓜汁是因为会产生颜色干扰；提取绿叶中的色素应该用深绿的菠菜叶作为材料，使用丙酮或无水乙醇作为溶剂；观察DNA在细胞中的分布，应用甲基绿作为染色剂，健那绿染液是线粒体的染色剂；观察叶绿体可用新鲜菠菜叶作为材料，并借助高倍显微镜观察。故不正确的是A、B、C。
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