单词	plasmid
释义	plasmid /ˈplazmɪd / noun Biology A genetic structure in a cell that can replicate independently of the chromosomes, typically a small circular DNA strand in the cytoplasm of a bacterium or protozoan. Plasmids are much used in the laboratory manipulation of genes. Compare with episome.The bacterium contains a plasmid, a circular piece of DNA that holds the gene and promoter sequence.... The replication control genes of bacterial plasmids face selection at two conflicting levels. We note, however, that few if any of the genes borne by bacterial plasmids are under strong positive selection at all times. Origin 1950s: from plasma + -id2.
随便看	fascist fascista fascistic fascistically fascistisation fascistise fascistised fascistization fascistize fascistized fascistoid fascist salute fascization fash fashion -fashion fashionability fashionable fashionableness fashionably fashionably late fashion buyer fashion-conscious fashion designer fashion editor

英语词典包含243303条英英释义在线翻译词条，基本涵盖了全部常用单词的英英翻译及用法，是英语学习的有利工具。