论文部分内容阅读
人身体里的所有细胞,除了再生性的细胞之外,都有固定的生命周期,在分裂到一定的次数之后细胞就死亡了。但是如果有可能使细胞分裂的进程永远进行下去,人就能长生不老。科学家们发现,控制每一个细胞生命的那些基因存在于染色体中,细胞每次分裂时,所有的染色体都要被复制到新的细胞中去。复制过程有可能使染色体受到破坏,但它们受到在染色体尾部一种冠状端粒的保护。如果把整个染色体比作一根鞋带,这个端粒就相当于鞋带端部那个硬的塑料
All cells in the body, except for regenerative cells, have a fixed life cycle, and after a certain number of divisions they have died. But if it is possible to keep the process of cell division going forever, one can live forever. Scientists have discovered that the genes that control the life of every cell are present in the chromosome, and every time the cell divides, all the chromosomes are copied into the new cell. Chromosomes may be destroyed during the replication process, but they are protected by a coronal telomere at the tail of the chromosome. If you compare the entire chromosome to a shoelace, this telomere is equivalent to the hard plastic on the end of the shoelace