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生物进化中 DNA 变化的本质是“封闭状态下老基因变为新基因”还是“开放状态下增加了新基因”,或二者兼有?进化过程中,生物的 DNA 含量有规律地增加。愈是高等生物,DNA 含量愈高,对这一规律最有说服力的解释是物种以微生物为媒介、转导、交流别的物种基因及整合病毒基因而增加了新基因,即基因的横向交流规律决定了 DNA 变化规律。请看事实:腺病毒所改变的哺乳类细胞含有20~80个病毒 DNA 的复本,而这种 DNA 最高可有5%成为细胞内 MRNA 的模板。以噬菌体的转导作用,一个菌株是 Phe~-Try~-Tyr~-
The essence of DNA change in biological evolution is whether the “old gene becomes a new gene in a closed state” or “a new gene is added in an open state”, or both? The biological DNA content regularly increases during evolution. The more advanced organisms, the higher the DNA content, the most persuasive explanation of this rule is the species of microorganisms as a medium, transduction, exchange of other species of genes and integration of the virus gene and increased the new gene, that is, horizontal gene exchange Law determines the law of DNA changes. Look at the fact that mammalian cells altered by adenoviruses contain copies of 20 to 80 viral DNA, and up to 5% of this DNA can become templates for intracellular MRNA. To phage transduction, a strain of Phe ~ -Try ~ -Tyr ~ -