I like all kinds of chocolate, especially bitter chocolate. So when Mother had bought one, I couldn't help thinking about 1.
I was helping Father in the yard when suddenly I got an idea. I could cut a piece 2that chocolate without anyone knowing it.
    I waited 3 Mother went outside feeding the chickens. Then I told Father I wanted to go for a drink of water. I went into the room and got the 4 down. Just when I had the knife ready to cut, I heard Mother coming. So I had to put the chocolate 5 into my shirt,
went to my mom and 6 the chocolate there. And then I went back to 7 Father.
    All the rest of the afternoon, I didn't dare to look at Father. Every time he spoke, it made me jump. My hands began shaking and my heart started 8 fast. I didn't want the chocolate any more. I 9 wanted to get a chance to put it back.
Have you ever had a similar 10?

2015年，屠呦呦因发现青蒿素治疗疟疾的新疗法获奖．工业上青蒿素一般从青蒿植株中提取，产量低，价格高．基因工程及细胞工程等为培育出高青蒿素含量的青蒿提供了思路．科学家先通过紫外线处理大量青蒿幼苗后，偶然发现一株高产植株．通过基因测序发现该高产植株控制青蒿素合成相关的一种关键酶的基因发生了突变．

（1）提取了高产植株的全部DNA后，要想快速大量获得该突变基因可以采用PCR技术，该技术的原理是____ 

（2）如果用青蒿某个时期mRNA反转录产生的双链cDNA片段，用该双链cDNA进行PCR扩增，进行了30个循环后，理论上可以产生约为____ 个DNA分子，该双链与载体连接后储存在一个受体菌群中，这个受体菌群就叫做青蒿的____ ，获得的cDNA与青蒿细胞中该基因碱基序列____ （填“相同”或“不同”）．

（3）将获得的突变基因导入普通青蒿之前，先构建基因表达载体，图l、2中箭头表示相关限制酶的酶切位点．请回答：

用图中的质粒和外源DNA构建重组质粒，不能使用SmaⅠ切割，原因是____ ，构建好的重组质粒在其目的基因前要加上特殊的启动子，启动子是____ 识别结合位点．

（4）检测目的基因是否表达出相应蛋白质，应采取____ 技术．目的基因导入组织细胞后，通过____ 技术培育出青蒿幼苗．

魔方可以看成是____。