问题
单项选择题
下列说法错误的有（）
①单倍体生物的体细胞中都只含有一个染色体组
②DNA分子中碱基对的增添、缺失和替换不一定都是基因突变
③基因突变的结果是产生新基因
④由受精卵发育而成的生物体一定不是单倍体
⑤非同源染色体片段的互换属于基因重组
A.一项
B.两项
C.三项
D.四项
答案
参考答案：C
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下列说法错误的有（）
①单倍体生物的体细胞中都只含有一个染色体组
②DNA分子中碱基对的增添、缺失和替换不一定都是基因突变
③基因突变的结果是产生新基因
④由受精卵发育而成的生物体一定不是单倍体
⑤非同源染色体片段的互换属于基因重组
A.一项
B.两项
C.三项
D.四项
参考答案：C
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