题干

某鲤鱼种群体色遗传有如下特征,用黑色鲤鱼(简称黑鲤)和红色鲤鱼(简称红鲤)杂交,F1皆表现为黑鲤,F1交配结果如表.

取样地点

F2取样总数/条

F2性状的分离情况

黑鲤/条

红鲤/条

黑鲤:红鲤

1号池

1 699

1 592

107

14.88:1

2号池

1 546

1 450

96

15.10:1

据此分析,若用F1(黑鲤)与红鲤测交,子代中不同性状的数量比是(  )

A:1:1:1:1

B:3:1

C:1:1

D:以上答案都不对

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答案(点此获取答案解析)

B

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    When I was a little girl, I remember that when my dad was repairing something,he would ask me to hold the hammer,so we would have time for a conversation with each other.I never saw my dad drinking or taking a night out. All he did after work was taking care of his family.

    I grew up and left home for college and since then,my dad had been calling me every Sunday morning.And when I bought a house several years later,my dad painted it by himself in the fierce summer heat.All he asked was to talk to him,but I was to busy in those days.

    Four years ago,my dad visited me.He spent many hours putting together a swing for my daughter.He asked me to have a talk with him,but I had to prepare for a trip that weekend.

    One Sunday morning we had a telephone talk as usual.I noticed that my dad had forgotten some things that we discussed lately.I was in a hurry,so our conversation was short.Several hours later that day I received a call.My father was in the hospital.Immediately I bought a plane ticket and on my way I was thinking about all the occasions I missed to have a talk with my dad.By the time I arrived at the hospital,my father had passed away.Now it was he who did not have time for a conversation with me.I realized how little I knew about my dad,his deepest thoughts and his dreams.

    After his death I learned much more about him and even more about myself.All he ever wanted was my time. And now he has all my attention every single day.