Question

multiple choice question

when the f factor is transferred by e. coli, ______.

no additional donor genes are transferred
a variable number of donor genes are transferred
a very few other donor genes are transferred
numerous other donor genes are transferred

Explanation:

Analyze standard F+ to F- conjugation

In standard conjugation mediated by an \(F^+\) donor cell, only the F plasmid (F factor) itself is replicated and transferred to the \(F^-\) recipient cell. The donor's chromosomal genes are not integrated with the F plasmid in this state, meaning no chromosomal (donor) genes are transferred during this process.

Evaluate the given options

• "no additional donor genes are transferred": This is correct because standard F factor transfer involves only the plasmid DNA.
• "a variable number of donor genes are transferred": Incorrect, as this describes Hfr conjugation, not standard F factor transfer.
• "a very few other donor genes are transferred": Incorrect, as no chromosomal genes are transferred.
• "numerous other donor genes are transferred": Incorrect, as this does not occur in standard \(F^+\) to \(F^-\) conjugation.

Answer:

• (A) no additional donor genes are transferred (Correct answer)
• (B) a variable number of donor genes are transferred
• (C) a very few other donor genes are transferred
• (D) numerous other donor genes are transferred