問一題關於後西生物 - 考試

In E. coli mating system, Hfr type could be a genetic donor and F- could be a
genetic recipient. After the mating between
Hfr and F- type cells, the F- recipient _____.
(A) becomes Hfr (B) becomes H+ (C) becomes F- (D) gets episome (E) remains F-

Ans. E

我的問題是 如果在長時間下 原本的F-不也是可以轉變成Hfr嗎?

請問我哪裡想法有問題? 麻煩各位了

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