Reproduction
Reproduction is a complex process that allows for diversity and genetic mutations to occur. The key to a species success is its ability to adapt to its environment. This usually occurs with Meiosis in sexually reproducing organisms. However, prokaryotes reproduce asexually through a process known as binary fission. This eliminates the mechanisms of variation that take place during sexual reproduction including crossing-over and segregation. Nonetheless, asexual reproduction in prokaryotes takes place at a high rate as a mate is not necessary to produce offspring. There are several ways that genetic information is diversified and changed during binary fission.
Firstly, mutations may occur during the replication of genes leading to changes in the genotype of the offspring. Although mutations are rare on an individual level, the high rate of reproduction allows mutations to have a greater effect on diversification than may be assumed. Transformation is another way that genetic information is modified. Scientists have observed in laboratories that bacteria may become pathogenic after being exposed to a pathogenic culture by incorporating the pathogenic information into its own DNA. This is known as recombinancy since the cell now possess genetic information from two cells. In his textbook, Biology, Reece et. al. states that "researchers have sinced learned that many bacteria have cell-surface proteins that recognize DNA from closely related species and transport it into the cell" (p. 561).
Yet another way for genetic information to be changed is transduction. This occurs when bacteriophages transfer genetic information from one cell to another. The "receiving cell" may then incorporate the recently injected genetic information into its own DNA composition and thus change the genotype of its offspring. Without these methods to create diversity, prokaryotes would not be nearly as successful and widespread as they are. Diversification is crucial to any organism's survival and prokaryotes are well-adapted to their environments due to the ability to quickly and regularly change as necessary.
References
Miller, B. (n.d.). Killer strain of E. coli Stalks Americans | MadMikesAmerica. MadMikesAmerica. Retrieved May 6, 2012, from http://madmikesamerica.com/2011/06/killer-strain-of-e-coli-stalks-americans/
Reece, J.B., Urry L.A., Cain, M.L., Wasserman, S.A., Minorksy, P.V., & Jackson, R. B. (2011) Campbell Biology. Boston: Benjamin Cummings.
Firstly, mutations may occur during the replication of genes leading to changes in the genotype of the offspring. Although mutations are rare on an individual level, the high rate of reproduction allows mutations to have a greater effect on diversification than may be assumed. Transformation is another way that genetic information is modified. Scientists have observed in laboratories that bacteria may become pathogenic after being exposed to a pathogenic culture by incorporating the pathogenic information into its own DNA. This is known as recombinancy since the cell now possess genetic information from two cells. In his textbook, Biology, Reece et. al. states that "researchers have sinced learned that many bacteria have cell-surface proteins that recognize DNA from closely related species and transport it into the cell" (p. 561).
Yet another way for genetic information to be changed is transduction. This occurs when bacteriophages transfer genetic information from one cell to another. The "receiving cell" may then incorporate the recently injected genetic information into its own DNA composition and thus change the genotype of its offspring. Without these methods to create diversity, prokaryotes would not be nearly as successful and widespread as they are. Diversification is crucial to any organism's survival and prokaryotes are well-adapted to their environments due to the ability to quickly and regularly change as necessary.
References
Miller, B. (n.d.). Killer strain of E. coli Stalks Americans | MadMikesAmerica. MadMikesAmerica. Retrieved May 6, 2012, from http://madmikesamerica.com/2011/06/killer-strain-of-e-coli-stalks-americans/
Reece, J.B., Urry L.A., Cain, M.L., Wasserman, S.A., Minorksy, P.V., & Jackson, R. B. (2011) Campbell Biology. Boston: Benjamin Cummings.