题目

A 答案：B  解析: 虎和狮是不同的物种，即使能产生后代，其后代也高度不育，原因是虎狮兽细胞核中无同源染色体，在减数分裂时不能产生正常的配子。这种现象也是生殖隔离的一种。所以虎狮兽再与虎或狮杂交，不能生出杂种后代，不能认为是动物中的一个新物种。情景反应。（共5分，每小题1分）从方框中选择恰当的句子完成下面的对话，请将符合题意的选项用2B铅笔涂在答题卡的相应位置上。A. Maybe we should do it again. B. Yes, I do.C. Well, what’s the weather going to be like? D. Oh, I’m cleaning my fishing rod(鱼钩).E. But don’t you have to study tomorrow? F. Do you want to go?G. We had some good times together.Son: Good morning, Dad. What are you doing?Father: 1.___________________ Have you remembered our fish trips?Son: Yes, I loved them.Father: Have you remembered catching your first fish?Son: How can I forget? 2.__________________________Father: So we did. 3.___________________________Son: How about tomorrow?Father: That sounds great4.________________________Son: Don’t worry. I don’t have much homework5.________________Father: Radio says sunny.Son: So we can do it tomorrow.Father:OK.