Tell me about the Endosymbiotic Theory?
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The endosymbiotic theory concerns the origins of mitochondria and plastids (e.g. chloroplasts), which are organelles of eukaryotic cells. According to this theory, these organelles originated as separate prokaryotic organisms which were taken inside the cell as endosymbionts. Mitochondria developed from proteobacteria (in particular, Rickettsiales or close relatives) and chloroplasts from cyanobacteria.
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In my own observation, all micro organisms puzzle the modern biologists, especially the inexplicable origin of the life force behind the protoplasm in the living nucleus.  All that they have done so far is to name and describe the composition (oxygen, hydrogen, carbon, nitrogen, calcium, magnesium, sulfur, potassium, etc.) and the observable phenomena surrounding the cell.  \n\nOn the othe hand, it is also possible that biologists understand this already, they are just trying to find the right time and the right words to make us understand.  As the saying goes: "The teacher will appear when the student is ready."
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I beleive this is the one:\n\nhttp://www.phy.ohiou.edu/~braslavs/Biophysics/Articles/Wei%20Zhang/Rosensweig2002.pdf
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well according to the most accepted theory of the origin of eukaryotes, no.  this is because eukaryotes actually have evolved from one prokaryote engulfing another prokaryote.  this leads to the symbiotic theory, where the "bigger" prokaryote protects the "smaller" eukaryote and uses the proteins it produces, while the "smaller" prokaryote protects the DNA, makes proteins, and is protected by the larger prokaryote.  in this manner, these multiple prokaryotes evolved to a eukaryote.\n\nso, no.
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I think more than any other thing--more than all other things combined, perhaps--there is a single, most important fundamental that must be understood: The Law of Mass Action.  The barrier to understanding evolution stems from the word "random."  We hear "random," and the instinct is to say, "Bull pucky."  But randomness, applied to the law of mass action, becomes every driving force in the universe, and the origin of all order.\n\nThis is a ubiquitous law in nature.  The hardest part of understanding something like evolution is trying to wrap your mind around the NUMBERS.  Those huge, infinitely-large number that are used to discuss propability are truly mind-boggling.  Once you realize that there are other examples of driving forces overcoming immense odds, your whole perspective on the probability of evolution changes.\n\nTake biochemistry.  This is some stuff that's completely undisputed.  A protein starts as a chain--or several chains--of amino acids, all strung together.  Miraculously, this protein folds into the specific conformation necessary to perform its function by the simple process of RANDONLY banging around.  That's it!  It just bangs this way and that, folds left and right, over and under, driven by nothing more than the RANDOM bumping and shifting caused by thermal energy bumping tiny articles against eachother.\n\nBUT!!!  Once it gets to a thermodynamically-stable conformation, it basically stays put.  It takes a million random bumps left and right, up and down, for each of the two joints connecting every individual amino acid on the thread, but once it goes the right way, it's mission is accomplished.  And all of this happens in the blink of an eye!  We have no concept of how incredibly quickly these minor bumps and bangs occur until the target reaches its mark.\n\nOr take diffusion.  This is an extrodinarily powerful driving force, and the law that governs it is so simple that it sounds absurd!  Here it goes:  It is more probable that something will go from where it is to where it isn't, than it is for something to go from where it isn't to where it is.  Done!  That's it.  I've just told you in a tiny nutshell what chemical engineers spend two years studying with differntial equations, labs, and computer models.  That's thermostatistics summed up.  And yet because I understood that very basic fact, I was able to understand the complex functions of the nerve cell far better than 99% of my molecular biology classmates.\n\nBear with me a bit longer: when a neuron fires, ions rush in and out of the cell in ways that depolarize and repolarize the electrical charge of the membrane.  It's really complicated-sounding stuff.  But what it really boils down to is that potassium ions (K) are concentrated in one place (mostly inside the cell), and sodium ions (Na) are concentrated somewhere else (mostly outside the cell).  All of these ions are banging around, this way and that.  Some go left, and some go right, but the membrane staps them from going through.  The special channels open up.  Na ions, being mostly outside the cell, will be far more likely to go inside the cell--where they aren't--than they are to come out of the cell--where they already are.  THat's all it is--you're more likely to go from where you already are to where you aren't than vice-versa.  It's so simple it stupid.  Yet the movement of any GIVEN ION is COMPLETELY RANDOM--and yet this action happens so quickly and so consistently and so reliably that this become the driving mechanism of all biological activity.  This random ion movement, taken applied to a massive system where thermal bumping happens millions of times per second for biliions of billions of ions happens in a reliable and concerted way every time you blink.  Every pixel you see on your screen right now is the product where trillions of random molecular collisions happened, but a handful of signific
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This is a great source for you:\nhttp://www.blackwellpublishing.com/ogunseitan/student.asp\nEnjoy the microbes!\n;-D
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>>>>>(IT IS NOT HOMEWORK! i am competing with a friend for the >>>>> best example)\n\nAnd cheating by asking strangers on the internet. I like the way you think.\n\nThe most extreme example of bacterial endosymbiosis amongst mammals is without a doubt the presence of mitochondria. You might not relaise it but mitochondria are stable line bacterial endosymbionts, complete with there own genetic structure. It's hard to top that.\n\nAfter that probably comes the entire rumen structure of ruminants. Its incredibly cmmplicated, but basically the stomach of cows and sheep is one massive bacterial fermentor. The cow eats grass but is totally unable to digest it. Instead it grinds the grass up fine and swallow sit to wet it. It leave sit in the stomach to fermenta while then brings it up to shew again after the bacteria have softened it. The food then goes back down for even more fermentation in the other three chambers of the stomach. To add to the elegance of this system cows don't just excrete their urea through their kidneys like other mammals. Urea is  a waste in mammals and is poisonous, but it is also a good fertiliser. Ruminants excrete their urea through their salivary glands. It then passes into the stomach and what was a poison to the cow becomes fertiliser for the bacetria, who convert the waste urea into protein that the cow can use. As a reuslt ruminants are the only mammals in the world tht can survive with no protein input intheir deit at all. Which explains why they have been so extraordinarily successful at surviving in harsh and low nutrient environments.\n\nLast comes the biosynthesis of vitamins. Mammals can't   make their own vitamins, they normally need to take it in on the food. However numerous mammals species from dogs to horses are able to harvest those vitamins from bacteria that grow in their guts. So although a dog lives on a diet that is horrendously deficient in 3 or four vitamins it never gets ill or needs to take vitamin tablets. Which is pretty clever.
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OK, what would you like to know, how to feed a paramecium or how it eats?\nIn any case, here is a great link that should help you find out EVERYTHING you did or did not want to know about them :-) They really are fascinating creatures!!\n\nhttp://www.101science.com/paramecium.htm
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mitochondria used to actually be separate bacteria (they think) and became symbionts of cells and eventually lost their ability to survive outside of the cell. one of the reasons why people came to believe this is because of their circular DNA, which is normally only present in bacteria.
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So funny thanks, have to tell my biology teacher that one, actually on second thoughts perhaps not the type of thing you tell your teacher. Thanks anyway xXx
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http://www.earthportals.com/Portal_Messenger/greer.html\n\nFrom this site I can gather that while Steven is not a complete idiot (he has a doctorate in something), he is not in any position to be making such claims (his medical doctorate is in trauma medicine... not astronomy, not general biology, not evolution not even environmental science).\n\nAs I go on to read the page's statement he sounds to me like a kind of interstellar James Lovelock, who pioneered the "scientific" Gaia Hypothesis.  This is where it gets sticky for me... I do somewhat believe in the Gaia Hypothesis (more in its interconnectedness than its ability to heal).  Carl Sagan opposed Lovelock and his hypothesis, and he is my hero so I've always been a little torn on the subject.\n\nI don't think there can be a universal Gaia Hypothesis which seems to be what Dr. Greer is hinting at because life is not connected between planets.  Obviously.  When we die on Earth microbes on Mars don't eat our bodies.  Billions of years later some of the atoms that were once in us might bombard an atom that used to be in a rock on Mars but we don't seem to have much effect on it.\n\nI read on... granted this is new to me, but the conscious oneness... is he saying that we are consciously connected? If this is even possible for humans, which is certainly debatable, I'd think we would notice strange influences from aliens.  But I'm not sure what he is talking about.  And then he states a lot of the obvious.\n\nNow... it might just be me, but in my years I have noticed that bullshitters tend to fallow a particular pattern.  Vague claims with almost nonsensical big words and no examples are fallowed or mixed in with precise and obvious claims that have very little to do with what they are talking about.  Such as "Collective mineral deposites are the very essence of our planet and souls or some similar entity is bound to manifest itself in such a hospitible and common location.   After all we've all seen rocks.  And we've all felt the presence of souls.  Allow me to introduce Occam's Razor..."\nHe is fallowing that format.\n\n\nDear sweet god, someone put this man in a Public Speaking class.\n\nShitloads of stating the obvious mixed in with obscure associations.\n\nReading the core principals I see that this has a critical flaw for the scientific community, it is seperating itself from science... he will never be able to prove this using science.\n\n"Even physical matter has an aspect of its nature which is non-local, transcendent and conscious"... rocks are conscious?\nLight is transcendent... in that it can instantaneously affect other light without transcending space.\n\nIn the second point this assumes that animals also have spirits... all living things, even plants and bacteria.  Fine, I'll go along with that.\n\nAh, here is his out.  The non-biological spiritual beings in point three... any discrepancies with the physical world can be blamed on those.  Sadly he says that they can affect the physical and that poses a problem since the physical world is described by science.\n\nBy his fourth point everything is everywhere?\n\nHis fifth point draws in faith again.  But most religions currently assert that only God is everywhere and in everything.\n\nWell in short, he isn't putting forth his arguments very clearly or giving support... red flag.\nHe is an MD in an unrelated feild.\nHis theories use too many different ideas from different areas needing different kinds of proof.  Most of this can either never be proven or is likely to be disproven.\n\nThe point of this seems to be to open our eyes to all sorts of life.  This is a good thing but he is going about it the wrong way I think.  Sure it is likely that life comes in many different forms that will look completely new to us but the ones we can have interactions with will be physical.  Ghosts and dreams and telepathic communications have some physical
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You've asked a rather broad question.\n\nHere's a good place to start:\n\nhttp://en.wikipedia.org/wiki/Kingdom_%28biology%29\n\nMore specific questions would be easier to answer.
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1.Mitochondria have a set of double membranes, as do most bacteria; and the lipid composition of mitochondrial membranes shows no similarities with the eukaryotic cell cytoplasm. If mitochondria evolved inside of proto eukaryote, their membrane composition would be expected to be of the same material. Instead, it appears that mitochondrial membranes more closely resemble bacterial membranes in terms of lipid composition \n\n2.The inner-membrane infoldings in the mitochondria lend more credence to the symbiosis theory. the infoldings (cristae) "are adaptations that increase the surface area of oxidative enzymes, evolutionary analogues to the mesosomal membranes of many prokaryotes" . In addition, the cristae keep the various enzymes segregated according to use, as do bacteria\n\n3.Mitochondrial ribosomal RNA sequences bear much more in common with bacteria than with ribosomes in the eukaryotic cytoplasm. For example, n-formylmethionyl transfer RNA has been found to exist only in mitochondria and bacteria \n\n4. Not only do mitochondria possess their own DNA, but it is circular, as is bacterial DNA; and DNA synthesis is continuous as opposed to that of eukaryotic nuclear DNA. Furthermore, the ratio of guanine-cytosine base pairs in mitochondrial DNA is proportionately higher, as with bacteria, than in eukaryotic nuclear DNA\n\n5.Mitochondrial division resembles bacterial reproduction.  "Genetic recombination in (mitochondria) is far more reminiscent of phage and bacterial sexuality than it is of eukaryotic nuclear sexual behavior
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About 2 billion years ago.\n\nVery little. We are reasonably sure that chloroplasts and mitochondria were bacteria before they joined the collective.
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Learn the theory. You do not have to believe it. Just smile, take the class, and read other books such as the one below...\n\nhttp://www.amazon.com/gp/product/0936728612/sr=8-5/qid=1150138605\n\n...or listen to this...\nhttp://marshill.org/audio/cosmos.mp3\n_________________________________\n\nSteel6in2k - That is a pretty arrogant thing to say.\n\nFrancis Collins\nhttp://www.genome.gov/10000779\n\nAntonie van Leeuwenhoek \nDiscoverer of Bacteria\n\nJohn Dalton\nFounder of Modem Atomic Theory\n\nGregor Mendel\nPioneer in Genetics
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Well, not to sure about your question... so I'll do my best.\n\nPositive interactions between microbes would be ones that cause a general benefit.  Like a bacteria excreting a certain amino acid that another bacteria would need in order to survive.\n\nNegative interaction would be microbes causing a detriment to each other.  Pencillium notatum generates an antibiotic naturally, causing a harmful environment to some bacteria.\n\nSymbiosis is two organisms living together in harmony.  If you refference Margulis's endosymbiont hypothesis, a large microbe, say an amoeba engulfs a photosynthetic bacteria.  The amoeba provides a safe location for the bacteria, and the bacteria provides energy to the amoeba.\n\nAntagonism... not to sure about this one.  Probably something of a parasitic interaction.
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http://www.soils.agri.umn.edu/academics/classes/soil3612/Symbiotic_Nitrogen_Fixation/Specificity.htm\nhttp://edis.ifas.ufl.edu/ag152\nhttp://jan.ucc.nau.edu/~gaud/bio326/class/ecosyst/Ncycling2.html