Bacteria primarily transfer genetic material through direct contact via a process called conjugation.
Here's a breakdown of the process:
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Conjugation: This involves one bacterium (the donor) directly transferring genetic material to another (the recipient). A special structure called a pilus forms a bridge between the two cells, facilitating the transfer. The donor bacterium contains a fertility factor (F-factor), a DNA sequence enabling it to initiate conjugation. The F-factor can exist as a plasmid (a separate circular DNA molecule) or be integrated into the bacterial chromosome.
- F+ Cell (Donor): Contains the F-factor (fertility factor).
- F- Cell (Recipient): Lacks the F-factor.
- Process: The F+ cell extends a pilus to the F- cell. A copy of the F-factor is transferred to the F- cell. The recipient cell then becomes F+, capable of initiating conjugation itself.
In summary, bacteria transfer genetic material via direct contact during conjugation, a process where the donor cell transmits DNA, often the F-factor, to a recipient cell.
