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To: gore3000
You keep lying about my postings even though they are just above, pretty shameless.

I think I've summarized your arguments fairly. You are, of course, free to differ, and free to say so.

Both mitochondria and chloroplasts can arise only from preexisting mitochondria and chloroplasts.

This is false.

No it isn't; it's completely accurate. If a cell's mitochondria or chloroplasts are destroyed they cannot be reginerated. These organelles are never assembled from scratch. They reproduce themselves within the cell by bianary fission (much like the bacteria from which they are descended). This is why mitochondrial DNA is passed on only from the mother. It is the mitochondria in the egg that reproduce as the fertilized ovum divides and are thereby passed on to the child. (I should say almost always. Very occassionaly a sperm will have some mitochondria -- normally they don't -- and very occassionaly these may be passed on. But the union of these two events is extremely rare.)

If you have evidence of mitochondria arising other than from prexisting mitochondria, then feel free to share it. But you don't because this doesn't happen, and the statement I posted is correct.

Since all eukaryotic organisms have one or the other

Well, you're batting a thousand so far. This isn't correct either. There certainly are eukaryotes that do NOT have mitochondria at all, and some lack chloroplasts as well (for instance the "pelobionts"). Some of them probably branched off from other eucaryotes before mitochondria were acquired, but in other cases there is evidence that mitochondria were lost secondarily (or evolved into relict structures that retain some functionality in supplying genetic material, but don't engage in metabolism of glucose). E.g.:

Direct Evidence for Secondary Loss of Mitochondria in Entamoeba histolytica

Archezoan protists are thought to represent lineages that diverged from other eukaryotes before acquisition of the mitochondrion and other organelles. The parasite Entamoeba histolytica was originally included in this group. Ribosomal RNA based phylogenies, however, place E. histolytica on a comparatively recent branch of the eukaryotic tree, implying that its ancestors had these structures. In this study, direct evidence for secondary loss of mitochondrial function was obtained by isolating two E. histolytica genes encoding proteins that in other eukaryotes are localized in the mitochondrion: the enzyme pyridine nucleotide transhydrogenase and the chaperonin cpn60. Phylogenetic analysis of the E. histolytica homolog of cpn60 confirmed that it is specifically related to the mitochondrial lineage. The data suggest that a mitochondrial relic may persist in this organism. Similar studies are needed in archezoan protists to ascertain which, if any, eukaryotic lineages primitively lack mitochondria.

and this is an essential function without the cell cannot survive they are an integral part of the eukaryotic cell.

Better. This is true as a rule of thumb -- as I've said, no one denies that modern mitochondria are highly integrated into the cell -- but it is false at the specific level because there are: 1) eucaryotes that get along quite well without mitochondria and/or chloroplasts (see above) and, 2) because in some heterotrophic protists mitochondria can be eliminated without harming the cell (granted these have chloroplasts).

these genomes are very small and cannot and could never have provided the essentials of life for any individual organism. [paragraph] The other similarities again do not speak to the problem that these could never have been individual organisms.

Of course they could not, as they exist now, but then this is a strawman. The endosymbiotic theory holds that the ancestors of mitochondria were intially engulfed as free living bacteria (there are plently of contemporary examples of this, btw) and then, over time, became symbiotic with their host, possibly starting out as parasites (there are also modern example of this happening), and then, again over time, developed the tight, integrated and obligate relationship we see today.

In short there is no evidence that these chloroplasts and mitochondria were ever anything but what they are now.

Like I said: bald assertion and sheer denial. The evidence is there as summarized. You are simply asserting that it couldn't happen, but all at least of the initial stages required by the endosymbiotic theory -- engulfment of one cell by another with the engulfed cell surviving and continuing to function and reproduce, the development of the engulfed cell into a parasite, the evolution of parasites into beneficial symbiots, the evolution of faculative symbiots into obligate symbiots -- have actually been observed to occur in modern examples.

41 posted on 10/18/2003 8:48:57 PM PDT by Stultis
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To: Stultis
these genomes are very small and cannot and could never have provided the essentials of life for any individual organism. [paragraph] The other similarities again do not speak to the problem that these could never have been individual organisms.-me-

Of course they could not, as they exist now, but then this is a strawman. The endosymbiotic theory holds that the ancestors of mitochondria were intially engulfed as free living bacteria (there are plently of contemporary examples of this, btw) and then, over time, became symbiotic with their host, possibly starting out as parasites (there are also modern example of this happening), and then, again over time, developed the tight, integrated and obligate relationship we see today.

Fact remains that regardless of the rhetoric the production of ATP is necessary. The endosymbiotic theory has absolutely no factual evidence behind it as you admit above. For it to be true both the prior ATP mechanism had to have dissappeared without a trace in all these organisms, the new parasitic organisms had to have reduced themselves (all of them the same way! in all organisms!) to unviable organs, and all examples of these original parasites must have dissappeared from everywhere. All of this shows my point quite well - that this is garbage, it is fact-free pseudo-science and there is no evidence for it except the need of evolution to make up a story to justify its theory in this very important and essential part of living organisms.

So what this discussion comes down to (which you will strenuously deny) is that my original statement is absolutely true - mitochondria and chloroplasts are original organs of eukaryotic organisms, just like many other organs in these organisms are original with them and cannot be claimed to have arisen as parasites. There is no evidence otherwise and the 'endoplasmic theory' is just more evolutionist made up nonsense.

To further complicate the problems that mitochondria create for evolutionists it should be noted that unlike other DNA, the genetic code of mitochondrial DNA is not only different from that of normal DNA but it also differs between species! Fredrick Sanger 1980 Nobel Lecture. So just more proof that this was not a parasite.

44 posted on 10/18/2003 9:55:08 PM PDT by gore3000 ("To say dogs, mice, and humans are all products of slime plus time is a mystery religion.")
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