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Transformation, Transformation is the uptake of genetic material from the environment by bacterial cells. In nature, this genetic material often comes from adjacent lysed bacteria and can include plasmid DNA or fragmented DNA released into the environment. Various factors promote natural transformation in different bacteria such as growth phase of the cells (Baltrus and Guillemin, 2006) or the presence of specific substances (Meibom et al., 2005)., Though not all bacteria are naturally competent to take up DNA, they can be made competent through chemical manipulation in the lab. This is commonly done using calcium chloride which permeabilizes the cell membrane so the bacteria can easily uptake your plasmid of interest. Scientists can also use electroporation, the application of an electrical charge to cells, to increase cell membrane permeability and thus transformation efficiency., Transduction, Transduction occurs when foreign DNA or RNA is introduced into bacterial or eukaryotic cells via a virus or viral vector., One example are bacteriophages that attach to bacterial membranes and inject their genetic material into the cell. Once inside, phages can follow one of two different life cycles: lytic or lysogenic. Lytic phages hijack the bacterial hosts machinery to make more viral particles. Eventually the cell lyses releasing the newly formed viral particles that can infect other bacteria. In the lysogenic cycle, the phage’s genetic material is incorporated into the host’s genome at a particular integration site. The integrated phage remains dormant until it is triggered to enter the lytic cycle., During both of these life cycles bacterial DNA can be accidentally packaged into the newly created phages. Transfer of this DNA to another cell is referred to as transduction. Transferred DNA once inside the infected bacterium can either exist as transient extrachromosomal DNA, like a plasmid, or it can integrate into the host bacterium’s genome through homologous or site directed recombination, Bacterial conjugation, During conjugation, genetic material is transferred from a donor bacterium to a recipient bacterium through direct contact. The donor bacterium contains a DNA sequence called the Fertility factor (F-factor). The F-factor is found on an episome, a piece of DNA that can replicate on its own or be integrated within a bacterial chromosome and allows the donor bacterium to make a small “bridge” or sex pilus that attaches to the recipient cell drawing it close. Once in contact the donor can transfer genetic material to the recipient bacterium. The genetic material transferred is commonly a plasmid and can infer genetic advantages such as antibiotic resistance.