题目

2013年，北京大学某研究团队成功地使用4种小分子化学物质，将甲小鼠的皮肤细胞诱导成全能干细胞（具有能发育成完整个体的潜能的细胞），并克隆出后代小鼠．下列相关叙述中，正确的是（ ） A . 诱导成的全能干细胞能进行细胞分裂、分化和生长 B . 甲小鼠能通过体内受精、卵生等有性生殖方式繁殖后代 C . 后代乙小鼠染色体上的DNA、基因和蛋白质是遗传物质 D . 穴居的小鼠嘴前端用来探路的胡须发达是“用进废退”的结果 阅读下列短文，从所给的四个选项中，选出最佳答案 　Once Peter went to stay with his uncle for a few weeks, who lived in the country．Whenever they went for a walk or for a drive in the car and they passed somebody, what surprised Peter was that his uncle waved．Peter said, “Uncle George, you know everybody here．Where did you meet them all?” 　“I don't know all these people,” said his uncle． 　“Then why do you wave to them?”asked Peter． 　“Well, Peter,”answered his uncle, “when I wave to someone and he knows me, he is pleased．He continues his journey with a happier heart．But when I wave to someone who doesn't know me, he is surprised and says to himself,'Who is that man? Why did he wave to me? ' So he has something to think about during the rest of his journey, and that makes his journey seem short．” 1．Who seemed to live in a city?[　　] A．George．　　　　　　  B．Peter． C．George and Peter．　　　D．The writer． 2．As we can learn from the passage, George was known by ______．[　　] A．any person he met B．few people he met C．some people in the country D．all people in the country 3．Whom did George wave to?[　　] A．Everybody that he met． B．Everybody that he knew． C．Those who were friendly with him． D．Those who said hello to him． 4．Which of the following best explains why Peter's uncle waved?[　　] A．He loved his home town． B．He expected to be respected by all． C．He tried to make his journey shorter． D．He wanted to make the person he met happy or surprised． 5．From the passage we can see that ______．[　　] A．Peter was a boy who always liked asking questions B．Peter would do as his uncle did C．George was a very strange man D．George would be more active on his journey