 Anonymous.2006. Exactly what is the meaning of life...? Virtual Genetics Information Centre. 2010.  Farabee, M.J. 2010. |
WELCOME! WELCOME! WELCOME! WELCOME! ... TO THE SECRET OF LIFE!!! The Big Question?What exactly is cell division, and how does it affect our lives?Answer:Cell division is the way in which cells replicate themselves to continue as a species. It is also the division and growth of cells in animals and other eukaryotic cells to replace damaged or worn out cells, or to help that animal to grow. It can also be the cause of cancer. There are three types of division: binary fission for prokaryotes, mitosis for eukaryotes and meiosis for eukaryotes. No matter which method is used, its all about replicating the DNA (deoxyribonucleic acid) and sharing it with the next generation. This is usually achieved through compacting the DNA into chromosomes (left picture). Interphase is the time when cells grow and prepare to divide. The cells do their usual work, as well as preparing copies of cell organelles and structures. The thing that is most unusual happens in the nucleus toward the end of Interphase. The very long, thin strands of DNA in each cell are copied and bound into chromosomes so that there will be the right number of each string of DNA in each cell's nucleus (even prokaryotes, which only have one DNA string or ring. Mitosis and binary fission helps to produce 2 new "daughter cells" assexually for each cell that undergoes cytokinesis. That means that any colony of prokaryotes are genetically identical, and that a particular type of prokaryotic cell is created through the division. or each cell that experiences the cell cycle. The only real diverisity to the process comes through the special cell division that is Meiosis. In the photo on the bottom left, you can see a colony of rod bacteria reproducing by binary fission. You can tell, because the bacteria are very long, and have grooves where cytokinesis will occur (I have circled some in white). The important thing to remember is that binary fission is efficient and easy on the cells, and all of the single bacteria in that picture are geneticallly identical continue to mitosis and meiosis...
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