①植物细胞细胞液中的有机酸会溶解膜结构；
②光学显微镜下观察，植物细胞看不到细胞膜；
③植物细胞的细胞膜较薄；
④植物细胞有细胞壁，提取细胞膜的过程比较繁琐；
⑤植物细胞内会有其他膜结构干扰．
Tomorrow we will go to Hainan. It's warm there. We will have a special Chinese New Year's Day. Now let's get ready! We need three tickets from Shijiazhuang to Hainan. We don't need winter clothes. I want a beautiful dress. My parents take some T-shirts and shorts. We need to take milk, cakes and fruit. We need three hats. The sun is very hot there. We don't want to turn black. That's all done.
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