Mitochondrion has its own DNA
* Mitochondria grow and multiply themselves through division in a coordinated process that requires the contribution of two different genetic systems: that of the organelle, i.e. the mitochondria, and that of the cell nucleus.
* From an evolutionary point of view it is suggested that both chloroplast and mitochondria find their origin in so called endosymbiotic bacteria. [In the endosymbion hypothesis eukaryotic cells started out in evolution as primitive organisms without mitochondria or chloroplasts and then established a stable endosymbiotic relation with a bacterium. This process is supposed to have occurred very early in the evolution of the eukaryotic cell, even before animals and plants separated].
* Little is known about how the nuclear and organelle genetic systems communicate in order to coordinate their contributions to the energy-organelle synthesis.
* If, for whatever reason, a functional genetic system is lost from an organelle, the cell cannot replace it. This has a detrimental effect on the function and life of the cells as well as the organism.
* The type of genetic analysis which makes the yeast mitochondrial genome so accessible to study is not possible with the human cells. Hence much of what we know through genetic analysis is true for yeast mitochondria, but is supposed to hold through extrapolation for human or animal mitochondria. With modern technology the genes are known now!
* Various antibiotics - such as chloramphenicol, tertracycline and erythromycin - inhibit protein synthesis in energy organelles. Normally antibiotics neutralise or kill bacteria.