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高中《生物》课本(1990年版)第201页提到“与正常的植株相比,单倍体植物长得弱小,而且是高度不孕的。”对这段话可作如下简单分析说明。单倍体是指体细胞中含本物种配子染色体数目的个体。单倍体可以来自正常的二倍体植物,也可以来自多倍体植物,来源不同,可育频度也有所不同。第一,来自二倍体的单倍体只有一个染色体组,在减数分裂时,没有相对应的染色体与之进行联合,所以只能随机分配到配子中去。只有在极少数的情况下,全组染色体都进入一个配子中形成可孕配子;几乎
High school “Biology” textbook (1990 edition), page 201, mentioned that “compared with normal plants, haploid plants grow weak, and is highly infertile.” For this paragraph can be briefly analyzed. Haploids refer to individuals whose somatic cells contain the chromosome number of their gametes. Haploids can come from normal diploid plants, but also come from polyploid plants, with different sources and different frequencies of fertility. First, haplotypes from diploids have only one genome. When meiosis occurs, no corresponding chromosomes are associated with them, so they can only be randomly assigned to gametes. In only a few cases, the entire group of chromosomes enters a gamete to form a gamete; almost