“观察根毛和根尖的结构”实验中，需要生出根毛的幼苗。在市场上购买葱等带根的植物，由于在其拔出和冲洗过程中折断了根尖，很难观察到根毛。我们采用“绿豆种子沙培发芽”的方法获取大量生出根毛的绿豆幼苗，时间短、用肉眼观察效果明显。方法如下：用烧杯或培养皿，在其底 In the experiment of “observing the structure of root hairs and apical roots”, seedlings of root hairs need to be produced. In the market, rooted plants such as green onions are purchased. It is difficult to observe root hairs because the root tips are broken during the extraction and washing process. We adopted the method of “sprouting the mung bean seeds by sand culture” to obtain a large amount of mung bean seedlings that produced root hair. The time was short and the effect was observed with the naked eye. The method is as follows: use a beaker or petri dish at the bottom