已知水稻高秆(T)对矮秆(t)为显性，抗病(R)对感病(r)为显性，两对基因

已知水稻高秆(T)对矮秆(t)为显性，抗病(R)对感病(r)为显性，两对基因独立遗传。现将一株表现型为高秆、抗病植株的花粉授给另一株表现型相同的植株，F1高秆︰矮秆=3︰1，抗病︰感病=3︰1。再将F1中高秆抗病类型分别与矮秆感病类型进行杂交，则产生的F2表现型之比理论上为 ( )

A.9︰3︰3︰1 B.1︰1︰1︰1 C.4︰2︰2︰1 D.3︰1︰3︰1

答案

相关题目

Henry escaped ____ by admitting his mistake. A. being punished B. having been p

Henry escaped ____ by admitting his mistake. A. being punished B. having been punished C. having punishedD. punishing

所谓合金,就是不同种金属(也包括一些非金属)在熔化状态下

所谓合金,就是不同种金属(也包括一些非金属)在熔化状态下形成的一种熔合物,根据下列四种金属的熔沸点:NaCuAlFe 熔点97.5℃1 083℃660℃1 535℃ 沸点883℃2

By the time he leaves, he ______ many friends here. A. has made B. will h

By the time he leaves, he ______ many friends here. A. has made B. will have made C. had made D. will make

Crime has its own cycles, a magazine reported some years ago. Police records th

Crime has its own cycles, a magazine reported some years ago. Police records that were studied for five years from over 2,400 cities and towns show a surprising link between changes in the season an

下列化肥不能与碱性物质混放或混用的是A．碳铵B．硝铵C．

下列化肥不能与碱性物质混放或混用的是A．碳铵B．硝铵C．硫铵D．硫酸钾

在人与自然的关系问题上，中国古代有过许多探索与思考。

在人与自然的关系问题上，中国古代有过许多探索与思考。据所学知识回答以下问题： （1）战国和两汉时期的思想家在自然现象与社会政治等方面的

2009年3月l1日，法国总统萨科齐宣布法国将重返北大西洋公约

2009年3月l1日，法国总统萨科齐宣布法国将重返北大西洋公约组织军事一体化机构，降下了“戴高乐主义”外交理念最张扬的一面旗帜。“‘戴高乐主义

— You didn’t tell me the truth about this matter, Barbara． — Are yo

— You didn’t tell me the truth about this matter, Barbara． — Are you _____ me of lying? A．charging B．reminding C．catching D．accusing

已知水稻高秆(T)对矮秆(t)为显性，抗病(R)对感病(r)为显性，两对基因

答案

相关题目

最新题目