Abstract
Seed plants propagate by sexual and asexual reproduction. This study investigated to what extent undergraduates and junior high school students understand the merits of sexual reproduction of seed plants. Subjects were asked why the seed plant propagates by seed while it propagates ascxually by subterraneans. Many of them pointed out the extension of the habitat of the plant as a main merit of reproduction by seed. Only about 20% of the undergraduates and 10% of the junior high school students pointed out the variety of an inherited character and the possible chance of adaptation of the plant to various environments. This fact means most of undergraduates and junior high school students do not understand one of the fundamental reason why seed plants propagate by seed. Obtained results were discussed from the standpoint of class work study of science.
