jimmydasaint

It is always tricky to think in that long time frames, especially in fast proliferating organisms. Nature does not care about that, of course (or about anything). But as I said it is likely that a redox enzyme "simply" switched substrate.

Now that is very interesting. I am sure that I attended a seminar which stated that enzymes shifted from an aqueous to an ethanolic environment or even in other solvents became efficient with completely new substrates. This is all speculation but I wonder if isolation of enzymes in 'microenvironments' caused the substrate switch?

Weird the link is correct, however I do not see any correlation to the sentence above. Anyway the key enzyme of nitrogen fixation is indeed the nitrogenase complex. If you are interested in the evolution, it is a slightly tricky thing as it is not as conserved as one might think. I recommend this paper:

 

Raymond et al 2004

The Natural History of Nitrogen Fixation

 

http://mbe.oxfordjournals.org/cgi/content/abstract/21/3/541

Thanks for that link. I read the abstract and the paper which is interesting in its phylogenetic diagrams. However, I still am a little confused. How would you propose that genes can be selected or diverge sufficiently to fix an atmospheric gas? I know that this event must have occurred for fixing carbon dioxide during photosynthesis and preceded animal life in the evolutionary time course, but...it is a hell of a puzzling process even given millions of years. There has to be some sort of advantage for survival in the stages that led up to efficient fixing of carbon dioxide and I cannot think of it at the moment.

I would love to make some biofuel for myself using vegetable oil, ethanol and a catalyst due to the prohibitively high cost of fuel at the moment and the probability that the cost will remain high in the future. The question is, will it be economical to do so or is it not worth the hassle?

Interesting points made in the OP, most of which have been already addressed. Suffice to say the DNA is actually active, not inert, during the main part of the cell cycle in Interphase. It is making and providing regulation for enzymes that speed up the chemical reactions of the cell. Enzymes are crucial to the functioning of the cell at the correct time and in the correct number.

I like the way you are trying to think independently. However, you would have more luck with debating the origins of and functions of RNA. Good luck.

Thanks for the reply. How does the mat give each device its required charge though?

I remember being quite excited by this charging mat when it first came out. apparently you could recharge any device after first plugging the mat into the mains. You could then automatically charge up any electronic device that contained rechargeable batteries. However, what has happened since and how does it work? Because I need one!

http://news.bbc.co.uk/1/hi/technology/2861987.stm

I would reply without doubt Cell Bology, but then I am speaking from the perspective of a British first Science degree. It was a fresh and rapidly changing science then and we had a professor who would sit in tutorials and wander off for a couple of hours telling us stories about his life and work and then pull us back on to topic in the last ten minutes. We also had to dredge through papers written on subjects that were controversial at the time such as phospholipid flip-flop and the phosphatidyl inisitol systems and thoughts about how facilitated diffusion occurred. Yet, thinking back on it I still remember the main parts of the course today. My title should really change from Quark to Old Fossil but ah....golden days, golden days!

Great Britain need a new anthem in contrast to the ponderous and old-fashioned anthem we have now. I suggest we pen some new lyrics to the Led Zeppelin tune 'Whole Lotta Love' and we can have the most energetic and enjoyable anthem in the world.

Are you talking about cognitive enhancement through the use of certain appropriate chemicals?

Thank you for that response. I have been forced to do some reading of my own and I now feel that we are in a sort of bubble embedded into a higher set of dimensions. The extra dimensions seem to be tightly curled into fractions of a centimetre tough. This article helped me out:

The Universe's Unseen Dimensions; August 2000; Scientific American Magazine; by Nima Arkani-Hamed, Savas Dimopoulos, Georgi Dvali, side bar by Graham P. Collins; 8 Page(s)

 

The classic 1884 story Flatland: A Romance of Many Dimensions, by Edwin A. Abbott, describes the adventures of "A. Square," a character who lives in a two-dimensional world populated by animated geometric figures-triangles, squares, pentagons, and so on. Toward the end of the story, on the first day of 2000, a spherical creature from three-dimensional "Spaceland" passes through Flatland and carries A. Square up off his planar domain to show him the true three-dimensional nature of the larger world. As he comes to grasp what the sphere is showing him, A. Square speculates that Spaceland may itself exist as a small subspace of a still larger four-dimensional universe.

 

Amazingly, in the past two years physicists have begun seriously examining a very similar idea: that everything we can see in our universe is confined to a three-dimensional "membrane" that lies within a higher-dimensional realm. But unlike A. Square, who had to rely on divine intervention from Spaceland for his insights, physicists may soon be able to detect and verify the existence of reality's extra dimensions, which could extend over distances as large as a millimeter ( 1/25 of an inch). Experiments are already looking for the extra dimensions' effect on the force of gravity. If the theory is correct, upcoming high-energy particle experiments in Europe could see unusual processes involving quantum gravity, such as the creation of transitory micro black holes. More than just an idle romance of many dimensions, the theory is based on some of the most recent developments in string theory and would solve some long-standing puzzles of particle physics and cosmology.

 

http://www.sciamdigital.com/index.cfm?fa=Products.ViewIssuePreview&ARTICLEID_CHAR=5E0C9057-3990-43A4-819C-09DEB18A335

This quite humorous and interesting blog also added more detail but more confusion for my tiny mind: http://backreaction.blogspot.com/2006/07/extra-dimensions.html

Could we just be four dimensional? I don't really know the answer to this

A puzzle I have been facing recently is to try to figure out how bacteria managed to capture nitrogen from the atmosphere to incorporate it as ammonia. I suppose I have always considered it similar to the method by which chloroplasts can incorporate atmospheric carbon dioxide into soluble carbohydrates. However, I don't know - it all looks so complicated. Any thoughts...

lucaspa

It was data that led to the hypotheses of duality and what happens at the quantum level. What data do you have that suggests "other worlds"?

I suppose what I meant was the possibility of the existence of other dimensions tightly curled and small but nevertheless theoretically possible. For example:

In physics, Kaluza–Klein theory (or KK theory, for short) is a model that seeks to unify the two fundamental forces of gravitation and electromagnetism. The theory was first published in 1921 and was discovered by the mathematician Theodor Kaluza who extended general relativity to a five-dimensional spacetime. The resulting equations can be separated out into further sets of equations, one of which is equivalent to Einstein field equations, another set equivalent to Maxwell's equations for the electromagnetic field and the final part an extra scalar field now termed the "radion".

 

http://en.wikipedia.org/wiki/Extra_dimensions

I think there are 11 dimensions theorised now. I just wondered if there is a possibility of extradimensional life forms (like ghosts etc...) which could accommodate paranormal wierdness.

foodchain thanks for the answer. I agree with you and it is a difficult point to answer. However, I suppose it is possible for RNA to code for a protein which then subsequently specifically modifies the activity of the RNA so perhaps I have answered my own question partially. It's just a matter of hypothesising when DNA came into the picture. However, I do take your points on board about the sheer complexity of the simplest biochemical pathways in bacteria.

In answer to the OP, I thinkI know what you are getting at. However, I think you are asking the question: 'Why do humans die?' despite having near perfect DNA and RNA polymerases and 'fail-safe' mechanisms. People will answer you with how, but not why - that is a mystery...

IMHO, the real problem is not with the technology which can solve food shortage problems or with the intentions of the scientists involved, it is with the greed of Biotechnology companies. If you can engineer crops that can grow in conditions of drought or in a nutrient-poor environment but do NOT produce seeds, you have a population of dependent poor farmers who will be forced to pay you annually just to stay alive. I think the ethics of genetic modifications of crops are questionable at the level of the companies and the Governments who use it as a means of social control.

Just to add to the points raised here, this information suggests:

that the origin of the mitochondrion was coincident with, and contributed substantially to, the origin of the nuclear genome of the eukaryotic cell. Defining more precisely the alpha-proteobacterial ancestry of the mitochondrial genome, and the contribution of the endosymbiotic event to the nuclear genome, will be essential for a full understanding of the origin and evolution of the eukaryotic cell as a whole.

http://www.ncbi.nlm.nih.gov/pubmed/10690412?ordinalpos=1&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_DiscoveryPanel.Pubmed_Discovery_RA&linkpos=4&log$=relatedarticles&logdbfrom=pubmed

In other words, mitochondria helped in the evolution of the host cell - Science is wierd!

I was just about to start a new thread on a similar topic, but this one will do!

I have been thinking about which came first - the gene or the protein that allowed the gene to be transcribed and translated?

I have read something about autocatalytic replication of RNA, but subsequent events become a little hazy.

Somebody out there must have a hypothesis...

Rather than starting another thread, can I please add to this interesting discussion, albeit with a slight digression. If a favourable mutation arose to allow high levels of cholesterol in a family without associated cardiac disease, but the family were in an isolated location (e.g. Milan, Italy), how would the gene be spread further than this location? Or does it just spread in that particular small location and stay there?

Well, mitochondria are a good example of bacteria that have evolved (in case someone mentioned it already and I overlooked it). Moreover, there are bacteria that have multicellular part of their life-cycle like e.g. Myxococcus xanthus. The problem with long-time bacterial evolution is that they simply do not leave us fossils to recognize changes over long time scales. In theory it should be possible to see the transition from one bacterial species, however it would require the sequencing of single cells, which, while in theory possible, is quite complicated to do.

I find mitochondria fascinating due to their close match to bacteria in terms of protein modifications and loose DNA structure (not packed in chromosomes like human DNA) and plasmids etc... Plants also have chloroplasts which seem bacterial-like in several respects. However, I don't know if I would classify that as an evolutionary event - I would rather treat it as a case of symbiosis with subsequent accommodation.

Good points guys and I loved that Brain in a vat article. However, does the duality of particles and quantum wierdness indicate that humans are in touch with a 'greater' power or a different dimension? I wonder why the human mind would come up with these concepts unless there are real other dimensions. More questions than answers, but the bottom line is:

Is quantum physics genuinely wierd or is it a pointer to other worlds we have no concept of?

Thanks for the reply RE. My question came from thoughts on the sheer power of mutation in bacteria and a multicellular organism like a fly and I wondered why they have stayed as they are for so long. You have partially answered ny question by saying that the original community have also survived after natural selection. I am aware of allopatric and sympatric speciation and it makes sense. However, something else comes to mind. If wolves are ancestors of dogs, does it mean that dogs are unable to breed with wolves? Because if the can breed then this is not classical speciation is it?

This is confusing to me because it would suggest that there is a possiblity, a glimpse of a greater reality and that quantum physics and quantum wierdness is tugging at the curtain which separates us from this reality.

This is pure speculation and therefore the topic belongs here. However, I have been having strange experiences recently causing me to believe that we are actually in a Matrix-like manufactured reality. My question would be:

How on Eart would you lnow the difference between a Matrix-type reality and our reality constructed by our 5 (or six) senses?

Forget the rainforest... we're finding new bacterial species on our own bodies!

 

 

i know , i was just trying to make a point, do you think the bacteria in our bodies, are perhaps evolving? that could be why we find so many new types of bacteria, like all the time.

If I understand you correctly, are you saying that the level of mutations are causing new species to arise on human bodies? Is there any evidence for this process? Also, if we look far enough back in the evolutionary tree, I think we may find a common ancestor cell but not necessarily a bacterium. Interesting points though...