高中生物《植物对水分的吸收和利用》一节中渗透作用演示实验,要在课堂上边讲课边演示,往往比较困难。本人通过多次实践,总结了以下几个方面的经验,可确保实验成功且效果明显。ａ.选膜。即半透膜的选择,最好选蛋的卵壳膜,而且鸭蛋优于鸡蛋,因为鸭蛋卵壳膜稍厚且面积大,易于包扎 The demonstration of penetration in the section “Plant’s Absorption and Use of Water by Plants” in high school biology is often difficult to demonstrate in class. I have repeatedly practiced and summarized the following aspects of experience to ensure the success of the experiment and the effect is obvious. a. Select the membrane. That is, the choice of semi-permeable membrane, the egg shell membrane is best to choose eggs, and duck eggs is better than eggs, because the egg shell egg membrane is a little thick and large area, easy dressing