Bacterial Conjugation: Plasmid Replication

Question:

During bacterial conjugation, where does plasmid replication occur?

A) the donor only

B) the recipient only

C) both the donor and recipient

D) either the donor or the recipient, but not both

E) neither the donor nor the recipient.

Final answer:

Answer:

Plasmid replication occurs in both the donor and the recipient bacteria during conjugation.

Explanation:

The correct answer is C) both the donor and recipient. In bacterial conjugation, a donor cell will replicate its plasmid (e.g., the F plasmid in E. coli), and transfer it to a recipient cell through a structure called a conjugation pilus. Conjugation is a primary process through which bacteria can share genes, thus enhancing genetic diversity among bacterial populations.

The donor bacterium forms a contact point with the recipient bacterium through the F pilus and creates a cytoplasmic bridge between the two cells. Replication of the donor's plasmid (using a method called rolling circle replication) allows a copy of the plasmid to be transferred to the recipient. Upon receiving the copied plasmid, the recipient bacterium can then replicate it to form a double-stranded, helical plasmid. This process enables both the donor and recipient bacterium to carry a copy of the same plasmid post-conjugation.