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本文是“观察胚珠”(本刊1965年第6期,已被选入到本刊编委会编的《中学生物实验与标本制作》一书中)一文的补充,下面介绍三种方法,根据具体情况可任选其一。不论哪种方法,在课堂上的操作过程都仅需要10分钟左右,具体作法如下: (一)春天,到果园结合疏花,可采集一批梨花或苹果花。当天或第二天上课前把花分放在培养皿里,上课时发给学生,先辨认花的各部分,然后左手持花柄,右手拿刀片,横切花托与子房合生的膨大部分;再用手持放大镜观察其
This article is “Ovule Observation” (issue of 1965 No. 6, has been selected into the editorial board of editors, “high school biology experiments and specimen making” in a supplement), the following three methods, according to Specific circumstances can choose one. Either way, the operation process in the classroom takes only about 10 minutes, the specific practices are as follows: (A) spring, to the orchard with thinning, you can collect a number of pear or apple flowers. On the day or the next day before the class, put flowers in petri dishes and send them to students in class. First identify the parts of the flower, then hold the flower stalk with the left hand and take the blade with the right hand to cross the enlarged part of the flower receptacle and the ovary. Then use handheld magnifying glass to observe it