RE: Unbroken Mitochondrial line?
April 9, 2017 at 12:21 pm
(This post was last modified: April 9, 2017 at 12:56 pm by Anomalocaris.)
(April 9, 2017 at 12:03 pm)Mermaid Wrote:(April 9, 2017 at 11:09 am)SamWatson Wrote: "completely different genetic structure". It is worth repeating: animals and humans have completely different genetic structure.
No, they really don't. Bacteria and animals have completely different genetic structures. This misquote makes it clear to me that you completely missed the basic premise: Mitochondria are the energy component in mammalian cells. They have different DNA than the rest of the cell. That is a fact.
I believe it's actually not quite that simple. Yes, mitochondria has its own DNA. But it is believed what DNA mitochondria still has left inside the mitochondria is but a tiny portion of the genome belonging to free living ancestors of mitochondria. Some of that ancestral genome is lost because it is no longer needed once mitochrondria became an endoparasite, but others migrated into the nucleus of the host cell and now form part of the nuclear DNA. These cell nuclear DNA remain vital to the functioning and reproduction of the modern mitochondria. So notion mitochondria DNA is completely separate from those of the host cell is not entirely true.
Portions of mitochrondria DNA is housed within the mitochondria and is passed on without mitosis. This means in all humans the portion of mitochondria DNA inside the mitochrondria is inherited largely without change solely from the mother. But other portions of it is housed with in the host cell nucleus and passed on through mitosis as an part of hoste cell's own DNA. These nuclear mitochrondria DNA is mixed between parents and strongly adulterated with each cycle of reproduction.
