《消化器官》一课中,有一个实验“唾液消化淀粉”确实难做,当了几年专职教师了,每次上这一课时,总担心实验不成功。教材上用稀淀粉加入唾液在温水中泡几分钟后,淀粉会沉入管底。滴入碘酒,开始还不变色,摇晃几下,沉淀在下面的淀粉又会遇碘酒变蓝,让试管内的液体又变成了蓝色,望 “Digestive organs” lesson, an experiment, “digestion of saliva starch,” really difficult to do, when a full-time teachers a few years, each time this class, always worried about the experiment was unsuccessful. Teaching materials on the use of diluted starch into the saliva After soaking in warm water for a few minutes, the starch will sink into the bottom. Into the iodine wine, began not to change color, shake a few times, the precipitation of starch in the following will turn blue iodine wine, the test tube of liquid has turned blue, hope