【单选题】【消耗次数：1】
下列极化状态描述哪项正确？
①
细胞膜外带有正电荷，细胞膜内带有同等数量的负电荷。
②
细胞膜外带有正电荷，细胞膜内带有不等数量的负电荷。
③
细胞膜外带有负电荷，细胞膜内带有同等数量的正电荷。
④
细胞膜外带有负电荷，细胞膜内带有不等数量的正电荷。
⑤
细胞膜外带有负电荷，细胞膜内带有同等数量的负电荷。
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关于细胞膜结构和功能的叙述，错误的是（）
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细胞膜是一个具有特殊结构和功能的半透性膜
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细胞膜的结构是以脂质双分子层为基架，其中镶嵌着具有不同生理功能的蛋白质
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细胞膜是细胞和它所处环境之间物质交换的必经场所
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⑤
水溶性物质一般能自由通过细胞膜，而脂溶性物质则不能
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