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观察植物细胞的质壁分离和复原实验是中学生物课中一个很重要的实验。在教学中,我对实验进行了如下改进,得到了良好的效果。 用氯化钠溶液代替蔗糖溶液:书本上是用30％的蔗糖液做植物细胞的质壁分离实验,存在着一些弊病:1)蔗糖液比较粘,学生在实验操作时稍不慎,就会把蔗糖沾在载物台上,甚至沾在镜头上,影响观察。2)蔗糖液价格比较贵,用量大,用6％的氯化钠溶液代替蔗糖液,比较经济实用,而且氯化钠溶液不容易沾在载物台上,也不容易沾在镜头上。
Observing the plasmolysis and reconstitution experiments of plant cells is a very important experiment in the middle school biology class. In teaching, I made the following improvements to the experiment and got good results. Instead of sucrose solution with sodium chloride solution: the book is to use 30% sucrose solution as a plasmolysis experiment for plant cells, there are some drawbacks: 1) sucrose solution is more sticky, students in the experimental operation is a little careless, it will Sticking sucrose on the stage, even on the lens, affects the observation. 2) The price of sucrose is relatively expensive, and the amount is large. Using 6% sodium chloride solution instead of sucrose solution is more economical and practical, and the sodium chloride solution is not easily stained on the stage and is not easily stained on the lens.