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问题 选择题

父亲有耳垂(A)为显性，母亲无耳垂（a）为隐性，生下的女儿无耳垂，则父亲的基因组成是（     ）

A.AA              B.Aa             C.AA或Aa             D.aa

答案

答案：B

因为无耳垂是隐性性状，所以女儿的基因组成是aa，那么有耳垂的父亲基因组成为Aa。

阅读理解

Dave Smith is 12. He has a sister .Her name is Jenny .She is 8.

Dave has a dictionary .It is blue .The dictionary is in his black backpack .He has a computer game and he likes it .Jenny has a watch .It is red .She likes it very much. She has a good pencil case ,too .It’s white . Her pencil  ,ruler ,eraser and pen are in the pencil case. Her pencil case is in her yellow backpack.

小题1:What’s Jenny’s family name?

A．White

B．Black

C．Smith

D．Brown小题2:What color is Dave’s dictionary?

A．It’s blue.

B．It’s black.

C．It’s red.

D．It’s white.小题3:_________ things are in Jenny’s pencil case.

A．One

B．Two

C．Three

D．Four小题4:What color is Jenny’s backpack?

A．It’s black

B．It’s red

C．It’s green

D．It’s yellow小题5: 下面哪项陈述是正确的？

A．Dave is 8

B．Jenny has a computer game

C．Dave’s backpack is black

D．Jenny has a sister
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名词解释

感觉性失语症
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