During conjugation, which structure forms the bridge for DNA transfer?

During conjugation, which structure forms the bridge for DNA transfer?

• A. Pilus
• B. Capsule
• C. Flagellum
• D. Cell Wall

Answer: (A)

During conjugation, the key idea is how two bacterial cells connect to exchange DNA. The donor cell builds a sex pilus, a thin proteinaceous appendage that reaches out to a recipient and pulls the cells together. This contact forms a stable mating bridge through which genetic material, typically the F plasmid (and sometimes chromosomal DNA in certain contexts), is transferred from donor to recipient. The capsule, flagellum, and cell wall aren’t involved in creating this DNA transfer conduit; they serve roles in protection, movement, or shape, but not in establishing the transfer bridge. Therefore, the structure responsible for forming the bridge is the pilus.

During conjugation, the key idea is how two bacterial cells connect to exchange DNA. The donor cell builds a sex pilus, a thin proteinaceous appendage that reaches out to a recipient and pulls the cells together. This contact forms a stable mating bridge through which genetic material, typically the F plasmid (and sometimes chromosomal DNA in certain contexts), is transferred from donor to recipient. The capsule, flagellum, and cell wall aren’t involved in creating this DNA transfer conduit; they serve roles in protection, movement, or shape, but not in establishing the transfer bridge. Therefore, the structure responsible for forming the bridge is the pilus.