bimmylee said:
Scoobes said:
bimmylee said:
ManusJustus said:
bimmylee said:
Endosymbiotic theory is far from foolproof.
There is no way for Mitochondria to live outside of the cell. There is also no way to prove that they ever did. Stating similarities proves nothing. The burden of proof is on the one making the claim; in this case, it is you with the claim that Mitochondria were once their own cells. It is impossible to prove this, because there is no record of it ever happening; if you actually tried to test it, you would lose every time.
If you have to make yourself feel better with cowardly attacks on one's level of education, of which you know nothing, then so be it. How big of you.
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A talking donkey told me it doesnt in a 2000+ year old book.
VS
Evidence that mitochondria and plastids arose from ancient endosymbiosis of bacteria is as follows.
- New mitochondria and plastids are formed only through a process similar to binary fission. In some algae, such as Euglena, the plastids can be destroyed by certain chemicals or prolonged absence of light without otherwise affecting the cell. In such a case, the plastids will not regenerate.
- They are surrounded by two or more membranes, and the innermost of these shows differences in composition from the other membranes of the cell. The composition is like that of a prokaryotic cell membrane.
- Both mitochondria and plastids contain DNA that is different from that of the cell nucleus and that is similar to that of bacteria (in being circular in shape and in its size).
- DNA sequence analysis and phylogenetic estimates suggests that nuclear DNA contains genes that probably came from plastids.
- These organelles' ribosomes are like those found in bacteria (70s).
- Proteins of organelle origin, like those of bacteria, use N-formylmethionine as the initiating amino acid.
- Much of the internal structure and biochemistry of plastids, for instance the presence of thylakoids and particular chlorophylls, is very similar to that of cyanobacteria. Phylogenetic estimates constructed with bacteria, plastids, and eukaryotic genomes also suggest that plastids are most closely related to cyanobacteria.
- Mitochondria have several enzymes and transport systems similar to those of prokaryotes.
- Some proteins encoded in the nucleus are transported to the organelle, and both mitochondria and plastids have small genomes compared to bacteria. This is consistent with an increased dependence on the eukaryotic host after forming an endosymbiosis. Most genes on the organellar genomes have been lost or moved to the nucleus. Most genes needed for mitochondrial and plastid function are located in the nucleus. Many originate from the bacterial endosymbiont.
- Plastids are present in very different groups of protists, some of which are closely related to forms lacking plastids. This suggests that if chloroplasts originated de novo, they did so multiple times, in which case their close similarity to each other is difficult to explain.
- Many of these protists contain "secondary" plastids that have been acquired from other plastid-containing eukaryotes, not from cyanobacteria directly.
- Among the eukaryotes that acquired their plastids directly from bacteria (known as Primoplantae), the glaucophyte algae have chloroplasts that strongly resemble cyanobacteria. In particular, they have a peptidoglycan cell wall between their two membranes.
- Mitochondria and plastids are just about the same size as bacteria.
http://en.wikipedia.org/wiki/Endosymbiotic_theory
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I almost feel like you're not paying attention on purpose.
There has NEVER been a recorded instance of a Mitochondria living on their own, as their own cell. Even IF they were once free-living bacteria, they would be expected to exhibit some vestigial remnants of their former condition... of which they have none. Notice how the word "similar" is so prevalent in this theory. It's the only thing it has to go by. Not actual proof. Sorry.
Also:
"A talking donkey told me it doesnt in a 2000+ year old book." Are you comparing Endosymbiotic Theory to some obscure children's book written by Julius Caesar? Because I know you're not talking about the Bible. Interesting.
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Actually, I think he was. And it was (at least the New Testament) written... well edited, by the Eastern Roman Emperor Constantine (Not ole' Julius Caesar). Basically he needed to unify religion in Eastern Rome and took all the gospels that refered to Jesus' divinity and took out everything else and made them heretical. Even Mary Magdalene supposedly had a gospel according to the Dead Sea Scrolls. Not to mention that Christmas was actually moved from the date of Christ's birth to coincide with the Winter Solstice to make it easier for Pagans to convert to the new religion. Constantine was also a bit of a nut-bar, he buried himself with 12 other tombs believeing himself to be the 13th disciple of Christ. Anyway, I've gone off topic and rambled, but one has to wonder how Christianity would have turned out without him.
Basically, in regards to the all the evidence presented, logic dictates that the most likely scenario is the endosymbiotic theory. To the bolded, half the things on that list are remnants of their former condition so I have no idea what you're on about. Idon't know what you contitute as "proof". You might as well say gravity doesn't exist because we can't see it, even though the effects are obvious.
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"Well-edited by Constantine?" Please tell me you don't believe fools like Dan Brown; Brown says that Emperor Constantine imposed a whole new interpretation on Christianity at the Council of Nicea in 325. That is, he decreed belief in Jesus' divinity and suppressed all evidence of his humanity. This would mean Christianity won the religious competition in the Roman Empire by an exercise of power rather than by any attraction it exerted. In actual historical fact, the Church had won that competition long before that time, before it had any power, when it was still under sporadic persecution. If a historian were cynical, you would say Constantine chose Christianity because it had already won and he wanted to back a winner.
But of course, some people apparently like to draw their historical arguments from works of fiction, such as "The Da Vinci Code." Anyways...
I admit, I made a mistake. Some of the items on the list would indeed appear to be vestigial remnants. I overlooked it. HOWEVER, you cannot equate such a theory to gravity, which can be easily TESTED, and its effects are visible and obvious. Unless you can explain how the Scientific Method can be used to test Endosymbiotic Theory (which would be interesting), then no, there is no proof. It is more of an educated guess than anything else.
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