题干

果蝇的翅有长翅和残翅两种,眼色有红眼和白眼两种,分别由A、a和B、b两对等位基因控制.甲图为某果蝇的染色体及基因组成,将该果蝇与“另一亲本”杂交,F1的表现型及其数量关系如乙图,请分析回答:

(1)甲图所示的果蝇体细胞有丝分裂后期移向两极的染色体上的基因组成分别是____ ;减数第一次分裂后期移向两极的染色体上的基因组成分别是____ ;减数第二次分裂后期移向两极的染色体上的基因组成分别是____ .

(2)分析甲、乙两图可知与该果蝇杂交的另一亲本的基因型为____ ,F1长翅红眼雌蝇中纯合体占的比例为____ .

(3)F1长翅红眼雌雄果蝇自由交配,F2中残翅白眼雌果蝇所占比例为____ ,残翅白眼雄果蝇所占比例为____ .

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同类题4

Read the passage and fill in the blanks with the proper words(在短文的空格内填入适当的词,使其内容通顺,每空格限填一词,首字母已给)
    A thousand years ago, Hong Kong was covered by a thick forest. As more and more people came to live in Hong Kong, these trees were cut down and burnt. Now there is no forest left, though there are still some small areas covered with trees. We call these “woods”.
    Elephants, tigers and many o____  animals were living in the thick forest. When people came to live in Hong Kong, the animals began to die out. Early farmers grew rice and r____  pigs and chickens in the valleys. They cut down the trees and burnt them. They needed fire to keep t____  warm in winter, to cook their food and to drive away the dangerous animals. Elephants quickly d____  because there was not enough food for them. So did most of the wolves and tigers.
    You might think that there are no longer any animals in Hong Kong e____  in the zoos, but there are still about 36 different animals living there. One of the most lovely of Hong Kong's animals is the barking deer. There are beautiful little animals w____  a rich brown coat and a white patch under the tail. They look like deer but they are much smaller. They are less than two feet high. They make a noise rather like a dog barking. In Hong Kong the barking deer has only one r____  enemy- men. People hunt these little animals though it is illegal(犯法的). There are now not many barking deer left. So it is important for people to protect these wild animals.