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一、基因使雄配子致死例1剪秋萝是一种雌雄异体的高等植物,有宽叶(B)和窄叶(b)两种类型,控制这两种性状的基因只位于X染色体上.经研究发现,窄叶基因(b)可使花粉致死.现将杂合子宽叶雌株与窄叶雄株杂交,其后代的表现型及比例正确的是().A.宽叶雄株∶宽叶雌株∶窄叶雄株∶窄叶雌株=1∶1∶0∶0B.宽叶雄株∶宽叶雌株∶窄叶雄株∶窄叶雌株=1∶0∶0∶1C.宽叶雄株:宽叶雌株:窄叶雄株:窄叶雌株=1∶0∶1∶0D.宽叶雄株∶宽叶雌株∶窄叶雄株∶窄叶雌株=1∶1∶1∶1解析由题意可知
First, the gene so that the male gamete death Example 1 cut autumn radish is a dioecious higher plants, wide leaf (B) and narrow leaf (b) two types of genes that control these two traits only in the X chromosome. The study found that, narrow-leaf gene (b) can pollen lethal. Now heterozygous broad-leaved plants and narrow-leaf male hybrids, the progeny phenotype and the correct ratio is () A. Broad-leaved male plants: Broad-leaved female plants: Narrow-leaved male plants: Narrow-leaved female plants = 1: 1: 0: 0 B. Wide leaf male plants: Broad leaf female plants: Narrow leaf male plants: Narrow leaf female plants = 1: 0: Broad leave male plant: Broad leave female plant: Narrow leaf male plant: Narrow leaf female plant = 1: 0: 1: 0 D. Broad leaf male plant: Broad leaf female plant: Narrow leaf male plant: Narrow leaf female plant = 1 : 1: 1: 1 resolution by the title we can see