题干

遗传学家研究玉米A,B,C,D,E五种基因和植株高矮的关系,这五种基因各有两个不同的等位基因,分别为:A1和A2;B1和B2;C1和C2;D1和D2;E1和E2.若只考虑单一基因效应,则不同基因型的平均株高如下表所示.下列说法错误的是(    )

基因型

株高

(cm)

A1A1

A1A2

A2A2

B1B1

B1B2

B2B2

C1C1

C1C2

C2C2

D1D1

D1D2

D2D2

E1E1

E1E2

E2E2

159

171

170

167

166

167

175

174

151

166

167

167

177

167

156

A:根据上表可以推定影响玉米植株高矮有关基因有A,C,E

B:B1B1和D2D2杂交后代株高在166cm左右

C:A1对A2为完全显性,B1对B2为不完全显性

D:C1对C2为完全显性,E1对E2为不完全显性

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C

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