如何保证众多的细胞生命活动在巨小的细胞核内有序进行？
参考答案：
形成相对独立的结构区域核被膜、染色质、核仁和核基质，由它们分别行使不同的功能，这是保证细胞核内各项生命活动有序进行的重要保证。
由核被膜上的核孔复合体完成亲核蛋白和其他小分子物质的入核转运；进入的调控因子和染色质上的特异DNA序列结合，调控染色质上DNA的复制、转录；转录产物在核基质中完成加工修饰后与核中的转运蛋白结合，通过核孔出核转运。同时，核仁上完成rRNA的转录加工、RNP颗粒的组装和加工，加工修饰后核糖体亚单位也通过核孔出核转运到细胞核，与细胞质基质中的mRNA结合表达蛋白。不同的生命活动分别在不同的结构区域中完成，而且各生命活动之间存在相互作用，这共同促使在巨小的核中生命活动的有序进行。
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| A girl complained to her father about her hard life. She wanted to 1 because she didn't know what she had to do. She felt 2 of fighting and fighting. When one 3 had been solved, another just came. Her father, a cook, took her into the kitchen. He 4 water into three pans. After boiling, in the first pan 5 some carrots, the second some eggs and the last was put with coffee. He waited without any 6 from his mouth. The girl closed her mouth and waited, 7 by what her father did. After about twenty minutes, her father 8 the stove and took out the carrots and the eggs. After that the coffee was poured into the cup. Turning back to her daughter, he asked,"What do you 9 ?" "Carrots, eggs, and coffee," she answered. Her father suggested her 10 the carrots. She did and felt the carrots were 11 . Then he asked her to take the eggs and break them. After 12 them, she got the eggs, cooked and hard. 13 , he asked her to smell the coffee. She asked 14 , "What's the meaning on earth, father?" He explained that 15 had experienced the same unfortunate-the boiling water, but made 16 responses. The strong and hard carrots became soft and weak after in the 17 water. The fragile eggs became hard after cooked. Coffee was very unique, but it could 18 water. " 19 are you?" asked her father,"When the suffering knocks at your door, how is your 20 ? Are you carrots, eggs, or coffee?" | ||||
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