问题
问答题 简答题
基因学说的主要内容。
答案
参考答案:
(1)种质(基因)是连续的遗传物质;
(2)基因是染色体上的遗传单位,有很高稳定性,能自我复制和发生变异;
(3)在个体发育中,基因在一定条件下,控制着一定的代谢过程,表现相应的遗传特性和特征;
(4)生物进化,主要是基因及其突变等。
这是对孟德尔遗传学说的重大发展,也是这一历史时期的巨大成就。
基因学说的主要内容。
参考答案:
(1)种质(基因)是连续的遗传物质;
(2)基因是染色体上的遗传单位,有很高稳定性,能自我复制和发生变异;
(3)在个体发育中,基因在一定条件下,控制着一定的代谢过程,表现相应的遗传特性和特征;
(4)生物进化,主要是基因及其突变等。
这是对孟德尔遗传学说的重大发展,也是这一历史时期的巨大成就。
I became lame(瘸的)in both legs in my childhood. I can’t stand 36 the support of two sticks. Only in my wheelchair can I “ 37 ”. I still remember the first day at 38 . When I appeared at the door, 39 in the classroom stared(凝视)at me in 40 . My face turned 41 . I couldn’t help 42 back. It was the 43 and sympathy(同情)in their eyes that 44 me doing so. I went shyly towards an unoccupied (空的) seat. Being lame, I didn’t dare (敢) to 45 in front of my classmates. I was afraid that I might be 46 at. In those days I was very sad to see others walking 47 . One day, a few students came up to me and asked me to go outside. I was really 48 . They encouraged me with a(n) 49 smile and 50 me in my wheelchair from place to place. I was 51 to them for giving me a chance to see the 52 of our lovely school with my own eyes. After that we often read, played and talked together. My friends are always 53 to help me. It made me 54 I am handicapped (残疾的). Once they asked me, “What is the most beautiful thing in our school?” Without hesitation (犹豫) I said, “It is the 55 . ”
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