Question

What are the genotypic differences between f- cells, f+ cells and hfr cells?

Answer 1

Hfr cells can become F+, but F+ cells cannot become Hfr. The fertility plasmid is integrated into the host cell chromosomal DNA in Hfr cells while the fertility plasmid is independent in F+ cells. Hfr cells are able to convert F- recipient cells to F+, but F+ cells are not able to convert F- recipient cells to F+.