Final answer:
Conjugation is the process in which bacteria transfer DNA to each other using pili, specifically a type known as the F pilus or sex pilus. This horizontal gene transfer contributes to genetic diversity among bacteria and is crucial in molecular biology.
Step-by-step explanation:
This type of gene transfer involves the formation of a physical connection between two bacterial cells. In particular, a sex pilus, or F pilus, facilitates the attachment of a donor bacterial cell to a recipient cell, forming a cytoplasmic bridge through which genetic material, typically in the form of a plasmid, can be transferred. F+ cells, or donor cells, contain a fertility factor known as the F plasmid, which encodes the necessary proteins for both the creation of the F pilus and the replication of the plasmid. F-cells, or recipient cells, do not possess this plasmid. Once DNA transfer occurs, recipient cells can potentially become donors themselves, fostering the propagation of the transferred genetic material through the bacterial population. This process is a form of horizontal gene transfer and contributes significantly to the genetic diversity among prokaryotic organisms, as well as playing a crucial role in molecular biology techniques such as molecular cloning.