题目

在某一人群中，已调查得知，隐性性状者为16%，则该性状不同类型的基因型频率分别是（按AA、Aa、aa顺序排列）（  ） A.0.36，0.48，0.16 B.0.48，0.36，0.16 C.0.16，0.48，0.36 D.0.16，0.36，0.38   答案：A  本题考查基因遗传平衡定律的应用。根据基因库中隐性性状者（aa）频率为16%。则q2=0.16，q=0.4，而p=1－0.4=0.6，根据遗传平衡公式，［p(A)＋q(a)］2=p2（AA）＋2pq(Aa)＋q2 (aa)可计算出AA的频率为0.36，A的频率为0.48，aa的频率为0.16。   用方框中所给词的正确形式填空(其中有两个词多余) 1．I knew he had seen me，but he did not come up to me．________, he didn’t want to talk to me． 2．The perfect ________ of Ma Lin and Chen Qi won the men-double in Athens Olympic Games． 3．She has ________ many important points in her presentation，so we can hardly understand her． 4．Thanks to the invention of the machine，many work processes have been ________． 5．The scenery in Guilin is so ________ that it attracts a lot of tourists to visit the city． 6．Many countries made an active ________ right after the launch of the Spaceship Shenzhou Ⅵ． 7．Both China and Vietnam are socialism countries，but the policies ________ a lot from each other． 8．Although we have made a great progress，if we ________ with them，we will find there’s still a long way for us to go． 9．The baby always laughs happily．It is very ________． 10．When having coffee，you had better ________ some sugar to it．