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细胞分裂是生物生长发育的基础,也是种族繁衍的基础。 细胞分裂的方式有无丝分裂、有丝分裂和减数分裂。大多数动植物的体细胞,是以有丝分裂的方式增加数目。有丝分裂的重要特征,就是亲代细胞中染色体经过复制后,平均分配到两个子细胞中去,使亲代和子代之间保持了遗传性状的稳定性。 减数分裂是动植物进行有性生殖的必然过程,对于维持每种生物前后代体细胞中染色体数目的恒定
Cell division is the basis for the growth and development of organisms and the basis for racial reproduction. The cell division has mitosis, mitosis and meiosis. The somatic cells of most plants and animals increase their numbers in a mitotic manner. An important feature of mitosis is that the chromosomes in the parental cell are evenly distributed into two daughter cells after replication, so that the stability of the hereditary traits is maintained between the parental and offspring. Meiosis is the inevitable process of sexual reproduction of animals and plants. It maintains a constant number of chromosomes in the somatic cells of each organism.