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新编十年制义务教育初中《生物》课本,把被子植物分类的内容由原来的10个科减为5个科。显然这5科是精华之精华了。为了减少篇幅和着重说明主要问题,教材仅概述了各科代表植物的花和果实的主要特点。这样,学生在阅读时就难免会有乏味之感。下面我们将教材述及的10种代表植物的有关知识作一介绍。 一、白菜 提起白菜,无人不知。但若问你我们课本上讲的到底是哪种白菜,恐怕你一时也难以回答。原因就在于白菜家族的成员很多,而且每一位都赫赫有名。这些成员按形态来分有:大白菜（Brassica pekinensis Rupr.）、小白菜（即青菜B.chinensis L.）、乌塌菜（ B.narinosa Bailey）、油菜（即芸苔B.campestris L.）、芜菁（ B.rapa L.）等。但根据细胞遗传学研究表明,这些成员的染色体数
The new 10-year compulsory education junior high school “biology” textbook has reduced the contents of angiosperms from the original 10 subjects to 5 subjects. Obviously these 5 subjects are the essence of the essence. In order to reduce space and focus on the main issues, the textbook only outlines the main characteristics of the flowers and fruits that represent the plants in each section. In this way, students will inevitably feel tedious when reading. Below we introduce the relevant knowledge of the 10 representative plants mentioned in the textbook. A. Cabbage When you mention cabbage, nobody knows. But if you ask what kind of cabbage we are talking about in our textbooks, I am afraid that you will find it difficult to answer. The reason is that there are many members of the cabbage family, and each one is famous. These members are divided into the following groups: Chinese cabbage (Brassica pekinensis Rupr.), Chinese cabbage (ie, B.chinensis L.), B.narinosa Bailey, and rape (B. campestris L.) , B.rapa L. and so on. But according to cytogenetic studies, the chromosome number of these members