The F plasmid, also known as the fertility factor or sex factor, contains approximately 100 genes. Through conjugation, the F factor allows genes to be transferred from a bacterium with the factor to a bacterium lacking the factor.
Conjugation is the fusion of two viable bacterial cells to transfer DNA to each other. During conjugation, gene transfer between bacteria is driven by a DNA plasmid, such as the F plasmid, in the bacterial cells. The plasmid is a circular strand of DNA. Once transferred, it can replicate its own DNA and be transferred to other bacterial cells. Since F plasmids can be easily replicated through intracellular means, they are maintained in the bacterial population.