题干

某同学在实验室中做“植物细胞的吸水和失水”实验时,在实验室老师的帮助下,进行了一系列的创新实验,实验步骤和现象如下表。

实验组

5 min的现象

再过5 min

滴加清水5 min

0.3 g/mL蔗糖溶液

x

无变化

质壁分离复原

0.5 g/mL蔗糖溶液

质壁分离

y

无变化

1 mol/L KNO3溶液

质壁分离

质壁分离复原

z

1 mol/L醋酸溶液

无变化

细胞大小无变化

细胞大小无变化

对上表的推断或解释错误的是   (    )

A:x为质壁分离,因为细胞壁伸缩性弱于原生质层

B:y为质壁分离,可能导致细胞失水过多而死亡

C:z为细胞稍增大,细胞液颜色逐渐变浅

D:④组无变化是因为细胞吸水量等于失水量

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D

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