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Describe the variations among general genetic code and those present in the mitochondria of some species. Also discuss selective advantage to the mitochondria code.
Introduction:
Mitochondria are essential organelles that are present in almost all cells in eukaryotic organisms. Mitochondria are called as semi-autonomous organelles because they have their DNA as genetic material which replicate independently and produce their mRNA, tRNA, and rRNA. For the translation of mRNAs, they also have their ribosomes but for many functions, mitochondria depend on nuclear genetic material. Mitochondria are considered to be originated from the endosymbiotic association which suggests that mitochondria are descended from the bacteria survived by endocytosis of the some other eukaryotic cell.
A worldwide (universal) genetic code is a group of rules which facilitate the conversion of information encoded by genetic material (DNA). Minute variations are observed between mitochondrial genetic codes and general genetic codes. I.e. A codon that encodes one amino acid in mitochondria encodes a different amino acid in the general genetic code.
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Genetic Analysis: An Integrated Approach (3rd Edition)
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