Mitochondria replicate their DNA and divide mainly in response to the energy needs of the cell. In other words, their growth and division is not linked to the cell cycle. When the energy needs of a cell are high, mitochondria grow and divide. When the energy use is low, mitochondria are destroyed or become inactive. At cell division, mitochondria are distributed to the daughter cells essentially randomly during the division of the cytoplasm. Mitochondria divide by binary fission similar to bacterial cell division; unlike bacteria, however, mitochondria can also fuse with other mitochondria.TRUE OR FALSE: Mitochondria controls their own reproduction?
False - biogenesis is controlled in coordination with the cells other responses to stress.
The organelle is semi-autonomous but the greater part of its genome is in the nucleus. Thus the reproduction is under the nucleus' control, responding to cell division and physiological stresses, and not the mitochondria's control. However the exact pathway for biogenesis is yet to be worked out but mitochondrial transcription factor A (mtTFA) is key to the process of mammalian mitochondrial replication in responce to stress. mtTFA is on chromosome 10 of the nucleus.
http://www.sciencedirect.com/science?_ob鈥?/a>
Though mitochondria have lost or transfered some of their genome to the cell nucleus they do still retain many. Human mitochondria retain some 37 genes, 13 are critical for cellular respiration. They translate their own mRNA on mitochondrial ribosomes but the nuclear genes are translated cellularly and the proteins are imported for use.
http://www.ncbi.nlm.nih.gov/pubmed/10412鈥?/a>
http://www.bmb.leeds.ac.uk/illingworth/o鈥?/a>
http://www.jbc.org/cgi/content/abstract/鈥?/a>
http://en.wikipedia.org/wiki/Mitochondri鈥?/a>TRUE OR FALSE: Mitochondria controls their own reproduction?
False. They produce energy.
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