题目

黄色圆粒和绿色圆粒豌豆杂交,两对相对性状独立遗传,对其子代的性状表现进行统计,结果如图所示,则杂交后代中,新性状表现个体占的比例为A. 1/3 B. 1/4 C. 1/9 D. 1/16 答案:【答案】B【解析】新性状个体是指与亲本的表现型不同的个体,本题根据子代的性状分离比推出亲代的基因型和表现型,按着分离定律一对对的考虑。设控制颜色的基因为(A、a),控制形状的基因为(B、b),子代黄色和绿色比值为1:1,则亲代的基因型为Aa和aa,子代圆粒和皱粒的比值是3:1,则亲代基根据句意和汉语注释,写出单词的正确形式。【1】She caught a _________(发烧) on her travels in Africa, and came back soon.【2】It is _________ (确定的) that nothing is impossible if we never give up.【3】He’s a deep sleeper and we _______(摇动) him for a long while to wake him up yesterday.【4】Hu Ge is popular ___________ (到处) for his TV play Nirvana in Fire(琅琊榜) these days.
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