Development of laboratory exercises for studying "Plant growth and morphogenesis" in upper secondary school biology.

通过对现有中学生物教材的分析，认为在植物生长和形态发生方面，学生的实验练习不够。我们的研究项目是为了开发既简单又有用的实验练习来研究高中生物的这些主题。研究内容包括教材的开发、实验条件的考察和实验程序或设备的简化。“细胞分裂素对离体黄化黄瓜子叶变绿膨胀的影响”和“利用常绿树枝检测成熟果实产生的乙烯”两个模块似乎对研究植物生长物质的作用很有用。另外三个模块“豆科植物小叶的睡眠运动——光敏色素介导现象”、“光对黄化芸豆幼苗上胚轴钩子展开的影响”和“光对种子萌发的影响”，似乎对研究光对植物生长和形态发生的影响有帮助。为了检验光的效果，单色光的提供是获得良好效果的必要条件。除了普通荧光灯和滤色器外，我们还使用了用于农业光周期调节的特殊荧光灯，以获得不同波长的光。上面列出的一些模块在高中生物课上进行了测试，并证实了它们的实用性。

After analyzing the present biology textbooks prepared for the secondary level, we concluded that not enough laboratory exercises are offered for the students to study plant growth and morphogenesis. Our research project was organized to develop laboratory exercises which are both simple and useful for studying these topics in upper secondary school biology. The research included the exploitation of teaching materials, examination of experimental conditions and simplification of experimental procedure or apparatus.Two modules, "Effect of cytokinins on the greening and swelling of the excised etiolated cucumber cotyledon" and "Detection of ethylene evolved from ripening fruits by use of an evergren twig" seem to be useful for studying the action of plant growth substances. The other three modules, "Sleeping movement of leaflets of Leguminosae - a phytochrome mediating phenomenon' "Effect of light on the uncurling of the epicotyl hook in etiolated kidney bean seedlings" and "Effect of light on the seed germination", seem to be useful for studying the effect of light on the plant growth and morphogenesis.For examining the effect of light, the supply of monochrome light is necessary to get a good result. Besides ordinary fluoresent lamps and color filters, we used special kinds of fluoresent lamps which are used for the regulation of photoperiodis in agriculture to obtain different wavelengths of light.Some of the modules listed above were examined in upper secondary school biology classes and their usefulness was confirmed.