下列关于以自然选择学说为核心的现代生物进化理论的观点中，正确的是（    ）

①环境改变使生物产生适应性的变异 ②隔离是新物种形成的必要条件 ③变异是不定向的④变异是定向的 ⑤自然选择使种群的基因频率定向改变，并决定生物进化的方向

46．①、②、③、④、⑤是使用操作显微镜的几个步骤。下图为显微镜观察中的两个视野，其中细胞甲为主要观察对象，由视野(1)到视野(2)时，操作过程中的正确顺序是
①转动粗准焦螺旋  ②转动细准焦螺旋  ③调节光圈
④转动转换器      ⑤移动玻片

①匪警电话“110”------负责处理各种刑事案件和社会治安及危害国家安全等案件②报案电话“122”----负责处理各种突发事件③火警电话“119”-------负责处理各种火灾④急救中心求救电话“120”--------负责处理各种突发的严重疾病和受伤

读下图：20世纪50年代，一位农民创作了一首“大麦穗、大玉米，运到北京去见毛主席”的民歌。你认为这首民歌的创作时代是（    ）

    Once upon a time, there was a very young mouse who had never seen anything of the world. He almost got into trouble the very first time he went out. This is the s____ he told his mother about his adventures.

     “I was walking along very quietly when I saw two strange creatures（生物）. One of them had a very kind look, but the other was the most frightening monster you could i____ 

     “On top of his head and in front of his neck, there were pieces of red meat. The moment he saw me, he o____ his mouth as if he wanted to swallow me. Then he let out a roar that frightened me almost to death.”

     “I wanted to make friends with the pretty creature because it looked s____good and gentle. He had thick and smooth fur and a gentle face. His eyes were bright and shining. As he looked at me, he w____ his fine long tail and smiled.

     “My son,” said the mother mouse, “that gentle creature you saw was the cat. In fact the cat eats us. Under his k____appearance, he was against every one of us. The other was nothing but a cock who wouldn't be h____ to you at all. So you're lucky, my child. ”