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初中《动物学》教材第7页,关于草履虫的采集和培养,有这样一段话:“……还可将稻草秆切成1寸左右的小段,浸泡在盛有淡水的培养器里,放在温暖的地方,过两周后,在液体上层可以看见很多游动的小白点,这就是草履虫”。我认为这句话说得不准确,容易使人误认为草履虫是由稻草长出来的,同时在实践中,有的同学根据上述方法做实验,并未培养出草履虫。其关键是没有介绍出稻草秆上要粘有草履虫的胞囊。因此,我建议将上述方法修改如下:
On the seventh page of Junior Zoology’s “Zoology” textbook, on the collection and cultivation of paramecium, there is such a paragraph: “...it is also possible to cut the straw into small pieces of about 1 inch, soak it in an incubator containing fresh water and place it. In warm places, after two weeks, there are many small white spots that can be seen on the upper layer of the liquid. This is Paramecium.” I think this sentence is inaccurate, it is easy to make people mistakenly believe that Paramecium grows from straw. At the same time, in practice, some students did experiments based on the above methods, and did not develop Paramecium. The key point is that the cysts to which straw worms are stuck on rice straw are not described. Therefore, I propose to amend the above method as follows: