How does an f + cell differ from an hfr cell? how does an f + cell differ from an hfr cell? hfr strains have the f plasmid integrated into the chromosome. f + cells have no plasmids. hfr cells cannot perform conjugation. hfr strains can no longer reproduce?

The correct answer is "Hfr strains have the F plasmid integrated into the chromosome".

This is in the context of horizontal gene transfer in bacteria. This gene transfer consist of transferring an "F plasmid" in a process called bacterial conjugation. Bacteria with the F plasmid are termed as "F + strains". The key difference between an Hfr strain and a F + strain is that while they both have the F plasmid; the Hfr strain have the F plasmid integrated to its chromosome while the F + strain have the F plasmid not integrated to the genetic material and only freely floats in the cytoplasm.