初中植物学有关呼吸作用的实驗是把一盆绿色植物用玻璃罩罩住,里面放一杯石灰水。由于CO_2的作用石灰水可以变混浊了,但是在黑暗下經过一两天,石灰水在多数情况下,除了表面浮了一层白色薄膜外,并不能显示得很混浊,而且又由于不是当场起变化的,给学生的印象不深。并且要密閉涂油也不太方便。作者根据自己的經驗,改进装置及操作过程如下:(1)试验前 Junior high school botany breathing experiment is a pot of green plants covered with glass, which put a glass of lime water. Lime water can become turbid due to the action of CO2, but after a day or two in the dark, in most cases lime water does not appear to be turbid except for the white film floating on the surface, From the change, the impression to the students is not deep. And to seal the oil is not too convenient. The author based on his own experience, to improve the device and operation process is as follows: (1) before the test