In asexual reproduction a cell makes an exact genetic copy of itself. The offspring are called clones of the parent. The group resulting from repeated reproduction is known as a clonal population because every member is identical to every other member. There are three ways in which genetic materials from two sources can be combined: conjugation, transformation and transduction.
Conjugation is the direct transportation of genetic information between cells. Two cells are drawn together by the pilus of the fertile cell. Then a copy of the fertility factor is transferred to the recipient cell. The result is two fertile cells.
In transformation a new combination of genetic material is created when cells take up DNA from the medium around them. Cells that are able to do this are known as competent.
Finally, in transduction a phage or a virus injects nucleic acid into a host cell where it is replicated into viral coat proteins. The viral nucleic acid is packaged into the new virus coats and new virus particles are released.
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