What came first? The chloroplast or the mitrochondria?

[Genecks]

what would be the result when chloroplast been injected into the egg? will number of chloroplast increase or not after few days?

 

Maybe increase the toxicity for the egg. But in general, those chloroplasts are going to degrade.

 

No, the number of chloroplasts would not divide. The ability is not programmed into the chicken egg's genome.

 

 

Like their ancestors, chloroplasts use a bacterial division system based on the FtsZ ring and some associated factors, all of which are now encoded in the host nuclear genome.

 

source:

Origin and evolution of the chloroplast division machinery

Journal Journal of Plant Research

Publisher Springer Japan

ISSN 0918-9440 (Print) 1618-0860 (Online)

Issue Volume 118, Number 5 / October, 2005

Category Invited Article

DOI 10.1007/s10265-005-0226-2

Pages 295-306

Subject Collection Biomedical and Life Sciences

SpringerLink Date Tuesday, September 06, 2005

[kitkat]

The mitochondria came before chloroplasts simply because animals were already here in the ocean. Chloroplasts are viewed currently as colonies of cyanobacteria that make up the chloroplast cell. The plankton, algae consists of cyanobacteria. Before expanding to land, an organism that can make its own food is necessary to support life on land. Cyanobacteria in the form of algae, plankton feeds the next level of life in the oceans. Some of the offspring of cyanobacteria (chloroplast) merged with a eukaryote to form plant life which eventually created the path of life to evolve on land.

 

In other words, photosynthesis using light energy was first but the organism responsible for it did not form a merger with a mitochondria eukaryote (chloroplasts) until expanding to land.

Edited September 5, 2010 by kitkat

[Asyncritus]

The mitochondria came before chloroplasts simply because animals were already here in the ocean. Chloroplasts are viewed currently as colonies of cyanobacteria that make up the chloroplast cell. The plankton, algae consists of cyanobacteria. Before expanding to land, an organism that can make its own food is necessary to support life on land. Cyanobacteria in the form of algae, plankton feeds the next level of life in the oceans. Some of the offspring of cyanobacteria (chloroplast) merged with a eukaryote to form plant life which eventually created the path of life to evolve on land.

 

In other words, photosynthesis using light energy was first but the organism responsible for it did not form a merger with a mitochondria eukaryote (chloroplasts) until expanding to land.

 

The earliest living organisms known are the cyanobacteria (called blue-green algae once upon a time). If anyone knows of anything earlier, please let me know. They're there in the pre-Cambrian, in huge quantities.

 

Now here's a marvellous thing.

 

These cyanobacteria can do 2 miraculous things.

 

1 They can fix nitrogen and make it available to other life forms and

 

2 They can photosynthesise.

 

They also possess DNA, that miraculously complex substance, and let's not mention all the hugely complicated biochemical machinery needed to respire, reproduce, and perform the normal functions of life, all of which require proteins, which contain fixed nitrogen.

 

Now here are your problems.

 

1 Nitrogen fixation is an enormously difficult thing to do - because nitrogen is the most unreactive gas known (apart from the rare gases like helium , xenon etc)

 

Haber and Bosch only discovered how to do this in 1912, and they used temperatures of 400C, high pressures, and sophisticated catalysts. They got Nobels for their discoveries. http://thomashager.n...test-invention/

 

Other than that, nitrogen only combines with oxygen in nature at the temperature of lightning flashes (40,000C).

 

Now here are the most primitive organisms known - or nearly the most primitive - and here they are fixing nitrogen, at ambient temperatures yet. How did they manage to figure out that little thing?

 

2 Without fixed nitrogen, DNA is impossible - because nitrogen features in a big way in the structure of the molecule. The nucleic acids all contain nitrogen which has been fixed, and without the nucleic acids, DNA is a non-starter.

 

But in the pre-Cambrian, nitrogen could not be fixed in any quantities without the cyanobacteria. (Apart from a few other restricted cases, like the bacteria in the root nodules of legumes, which didn't exist in the preCambrian).

 

But without the fixed nitrogen, the cyanobacteria cannot exist.

 

So which came first? This is an infinite loop: no bacteria, no fixed nitrogen; no fixed nitrogen, no bacteria.

 

So mitochondria? Wrong question. How did the cell walls and the great biochemical processes originate, is more apposite.

 

The cyanobacteria also photosynthesise, meaning they possess chlorophyll.

 

Now in case you don't know, chlorophyll is one of the most remarkable substances known, and the process of photosynthesis is nearly miraculous too. It is fiendishly ingenious: Melvin Calvin and his merrie men got Nobels for figuring out how it works.

 

Now how did a brainless bacterium figure out how to do that????

 

Does the whole thing not simply scream creation, design and magic?

Edited September 6, 2010 by Asyncritus

[Red Hypergiant]

"Brainless bacteria" didn't figure out how to do that. Evolution isn't about organisms choosing what new traits they want. It happens by variation, caused by things such as mutations, and then natural selection acting upon them.

 

The bacteria that predated cyanobacteria used a much simpler code than DNA, and slowly evolved the machinery to fix nitrogen and then develop a more complex code.

[immortal]

IMO they both co-evolved. But still I have to go with mitochondria because in the beginning there were anaerobic prokaryotes or ferementers and photosynthetic prokaryotes but these photosynthetic prokaryotes were able to produce glucose with out giving out molecular oxygen has a byproduct as they never used water to produce glucose and also these anaerobic prokaryotes were not that energy efficient as they were able to produce only 2 ATP molecules. It is also found that all three forms of life Eubacteria, Archae bacteria and eukaryotes were in existent near the end of archaean times and since eukaryotes had developed long before cyanobacteria started producing molecular oxygen this is irrelevant to the origins of mitochondria.

 

What we can speculate is that in the beginning the mitochondria might be a bacterial parasite like any other virus whose main aim is to replicate. It used the kind environment of the host to replicate itself but instead of destroying the host and migrating elsewhere, at some point in time those changes which helped to keep the host's environment organised and safe got selected and it become symbiont as it increased its chances of survival. Now this selection pressure of non-efficient energy production of the host also applied to the parasite and this selection pressure forced the parasite to invent oxidative phosphorylation which produces a total of 36 ATP molecules compared to 2 ATP molecules in anaerobic respiration.

 

Also I read that it is not that easy to produce glucose using natural processes as compared to oxydizing it. So those mechanisms like photophosphorylation and production of glucose using Melvin Calvin cycle had to be under immense selection pressure in order to discover it. I think this immense selection pressure came from the host's requirement for glucose to produce energy which had to come from a natural resource that was readily available.

 

From then on they might have exchanged their genes to remove burden on each other so that each concentrates on what it does best.

Edited November 7, 2010 by immortal

[kitkat]

The earliest living organisms known are the cyanobacteria (called blue-green algae once upon a time). If anyone knows of anything earlier, please let me know. They're there in the pre-Cambrian, in huge quantities.

 

Now here's a marvellous thing.

 

These cyanobacteria can do 2 miraculous things.

 

1 They can fix nitrogen and make it available to other life forms and

 

2 They can photosynthesise.

 

They also possess DNA, that miraculously complex substance, and let's not mention all the hugely complicated biochemical machinery needed to respire, reproduce, and perform the normal functions of life, all of which require proteins, which contain fixed nitrogen.

 

Now here are your problems.

 

1 Nitrogen fixation is an enormously difficult thing to do - because nitrogen is the most unreactive gas known (apart from the rare gases like helium , xenon etc)

 

Haber and Bosch only discovered how to do this in 1912, and they used temperatures of 400C, high pressures, and sophisticated catalysts. They got Nobels for their discoveries. http://thomashager.n...test-invention/

 

Other than that, nitrogen only combines with oxygen in nature at the temperature of lightning flashes (40,000C).

 

Now here are the most primitive organisms known - or nearly the most primitive - and here they are fixing nitrogen, at ambient temperatures yet. How did they manage to figure out that little thing?

 

2 Without fixed nitrogen, DNA is impossible - because nitrogen features in a big way in the structure of the molecule. The nucleic acids all contain nitrogen which has been fixed, and without the nucleic acids, DNA is a non-starter.

 

But in the pre-Cambrian, nitrogen could not be fixed in any quantities without the cyanobacteria. (Apart from a few other restricted cases, like the bacteria in the root nodules of legumes, which didn't exist in the preCambrian).

 

But without the fixed nitrogen, the cyanobacteria cannot exist.

 

So which came first? This is an infinite loop: no bacteria, no fixed nitrogen; no fixed nitrogen, no bacteria.

 

So mitochondria? Wrong question. How did the cell walls and the great biochemical processes originate, is more apposite.

 

The cyanobacteria also photosynthesise, meaning they possess chlorophyll.

 

Now in case you don't know, chlorophyll is one of the most remarkable substances known, and the process of photosynthesis is nearly miraculous too. It is fiendishly ingenious: Melvin Calvin and his merrie men got Nobels for figuring out how it works.

 

Now how did a brainless bacterium figure out how to do that????

 

Does the whole thing not simply scream creation, design and magic?

 

That depends on what the biota at the vents do to acquire nitrogen fixation in their cells. They do not require oxygen either. The vents are interesting in that a blanket of bacteria must colonize first before anything else higher can develop. This process seems to scream loudly of who is responsible for lifeforms with compartments that do very specific jobs within the body of a host. Can RNA alone require no nitrogen fixation to work prior to DNA that is more stable to accumulate information as it is compiled?

 

IMO they both co-evolved. But still I have to go with mitochondria because in the beginning there were anaerobic prokaryotes or ferementers and photosynthetic prokaryotes but these photosynthetic prokaryotes were able to produce glucose with out giving out molecular oxygen has a byproduct as they never used water to produce glucose and also these anaerobic prokaryotes were not that energy efficient as they were able to produce only 2 ATP molecules. It is also found that all three forms of life Eubacteria, Archae bacteria and eukaryotes were in existent near the end of archaean times and since eukaryotes had developed long before cyanobacteria started producing molecular oxygen this is irrelevant to the origins of mitochondria.

 

What we can speculate is that in the beginning the mitochondria might be a bacterial parasite like any other virus whose main aim is to replicate. It used the kind environment of the host to replicate itself but instead of destroying the host and migrating elsewhere, at some point in time those changes which helped to keep the host's environment organised and safe got selected and it become symbiont as it increased its chances of survival. Now this selection pressure of non-efficient energy production of the host also applied to the parasite and this selection pressure forced the parasite to invent oxidative phosphorylation which produces a total of 36 ATP molecules compared to 2 ATP molecules in anaerobic respiration.

 

Also I read that it is not that easy to produce glucose using natural processes as compared to oxydizing it. So those mechanisms like photophosphorylation and production of glucose using Melvin Calvin cycle had to be under immense selection pressure in order to discover it. I think this immense selection pressure came from the host's requirement for glucose to produce energy which had to come from a natural resource that was readily available.

 

From then on they might have exchanged their genes to remove burden on each other so that each concentrates on what it does best.

 

The key point is immense selection pressure so what would the environment be like for this to occur?

[CharonY]

The earliest living organisms known are the cyanobacteria (called blue-green algae once upon a time). If anyone knows of anything earlier, please let me know. They're there in the pre-Cambrian, in huge quantities.

This is incorrect. The rise of oxygenic photosynthesis is placed around 2.5 Gyr ago (studies that place it earlier are heavily contested). AFAIK the latest studies place cyanobacteria around 2.15 Gyr (and eukaryotes around 1.8 Gyr), but I may be remembering it wrong, it is just something I picked up talking with colleagues and I may be remembering the precise numbers wrong.

 

But in any case it would be at best in the late Archean, way later than the first prokaryotes. Also nitrogen fixation has evolved earlier than photosynthesis, especially considering that the nitrogen fixing apparatus is very sensitive against oxygen (something that the early prokaryotes did not have to worry about).

 

What you may have read is from a paper in the 90s (and which is erroneously propagated in many sources) in which it was claimed that records of cyanobacteria are way older. But this has been basically dismissed by now.

 

According to molecular clocking mitochondria evolved earlier. Evolutionary evidence favors the assumption that the rise of the first eukaryote is bound to the endosymbiosis with prokaryotes.

Edited October 28, 2011 by CharonY

[kitkat]

IMO they both co-evolved. But still I have to go with mitochondria because in the beginning there were anaerobic prokaryotes or ferementers and photosynthetic prokaryotes but these photosynthetic prokaryotes were able to produce glucose with out giving out molecular oxygen has a byproduct as they never used water to produce glucose and also these anaerobic prokaryotes were not that energy efficient as they were able to produce only 2 ATP molecules. It is also found that all three forms of life Eubacteria, Archae bacteria and eukaryotes were in existent near the end of archaean times and since eukaryotes had developed long before cyanobacteria started producing molecular oxygen this is irrelevant to the origins of mitochondria.

 

What we can speculate is that in the beginning the mitochondria might be a bacterial parasite like any other virus whose main aim is to replicate. It used the kind environment of the host to replicate itself but instead of destroying the host and migrating elsewhere, at some point in time those changes which helped to keep the host's environment organised and safe got selected and it become symbiont as it increased its chances of survival. Now this selection pressure of non-efficient energy production of the host also applied to the parasite and this selection pressure forced the parasite to invent oxidative phosphorylation which produces a total of 36 ATP molecules compared to 2 ATP molecules in anaerobic respiration.

 

Also I read that it is not that easy to produce glucose using natural processes as compared to oxydizing it. So those mechanisms like photophosphorylation and production of glucose using Melvin Calvin cycle had to be under immense selection pressure in order to discover it. I think this immense selection pressure came from the host's requirement for glucose to produce energy which had to come from a natural resource that was readily available.

 

From then on they might have exchanged their genes to remove burden on each other so that each concentrates on what it does best.

 

 

I read somewhere that according to genetics eukaryotes (multi-celled organisms) begin with mitochondria while few later lost it.

[immortal]

 

The key point is immense selection pressure so what would the environment be like for this to occur?

 

According to Endosymbiont theory, organisms can undergo secondary endosymbiosis, i.e for example - a protist can engulf a whole algae which itself is in symbiosis with a cyanobacteria or some other symbiont organism. Some organisms depend on other organisms for glucose as long as they are independent but once they have engulfed an autotroph they lose their scavenging charactersistics and start acting as an autotroph by moving towards light. These organisms become so completely dependent on its symbiont that they no longer

can exist individually, so as energy requirements of the host increased it required more glucose molecules and it had to come from the symbiont since the host was completely dependent on it. So it is this kind of environment of immense selection pressure led to the development of complex photosynthetic components and cycles. Remember generation of glucose is not a spontaneous process, it requires free energy. Read the article on Endosymbiont theory in wikipedia for further reference.

 

I read somewhere that according to genetics eukaryotes (multi-celled organisms) begin with mitochondria while few later lost it.

 

Yes research indicates that both Eukaryotes and mitochondria had to evolve simultaneously and since it has been known that eukaryotes might have existed prior or at the time of origin of oxygenated photosyntesis I have gone with mitochondria evolving first before the choloroplasts.

[kitkat]

According to Endosymbiont theory, organisms can undergo secondary endosymbiosis, i.e for example - a protist can engulf a whole algae which itself is in symbiosis with a cyanobacteria or some other symbiont organism. Some organisms depend on other organisms for glucose as long as they are independent but once they have engulfed an autotroph they lose their scavenging charactersistics and start acting as an autotroph by moving towards light. These organisms become so completely dependent on its symbiont that they no longer

can exist individually, so as energy requirements of the host increased it required more glucose molecules and it had to come from the symbiont since the host was completely dependent on it. So it is this kind of environment of immense selection pressure led to the development of complex photosynthetic components and cycles. Remember generation of glucose is not a spontaneous process, it requires free energy. Read the article on Endosymbiont theory in wikipedia for further reference.

 

 

 

Yes research indicates that both Eukaryotes and mitochondria had to evolve simultaneously and since it has been known that eukaryotes might have existed prior or at the time of origin of oxygenated photosyntesis I have gone with mitochondria evolving first before the choloroplasts.

 

How long after that do you think the chloroplasts came onto the scene after eukaryotes with mitochondria?