How did the genetic code originate?
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Right-the classic idea is that somehow nucleotides got together to form a self-replicating molecule (odds are that it was RNA at first, not DNA), and then these self-replicating molecules began to assemble amino acid chains, which, through uncounted bazillions of reacions (keep in mind whole oceans full of molecules, and billions of years) these amino acid/peptides began to have specific  functions.  The newest theory is that proteins formed (which is fairly easy with the right conditions), and some of these were captured in small mycells (little balls of lipids, which form naturally).  In some of them, the proteins interacted with each other to produce energy-generating reactions, and perhaps served as templates for formation of more of the same protein.  We now know this is as least theoretically possible, because of prion diseases, in which small proteins get into cells and cause generation of the same protein chain, independently of the DNA coding mechanism.  So, under this theory, you have mycells full of enzymes, energy-generating ( as in glycolysis or the TCA cycle) and only later did RNA or DNA come to play a role, as a more convenient and stable way to code for the proteins.  This makes a lot of sense biochemically, and is easier to visualize chemcically than the classic theory.  And, it makes sort of an elegant and chemically poetic argument that the origin of life was the thing that really makes life today-the proteins and the protein reaction-and relegates DNA to just a convenient way for the proteins to replicate.
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Gene Codes produce sequences\nseguence assembly & analysis can be found on genecodes.com\nHope this will help
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First, I think a lot of people here don't understand what is meant by the genetic code being the same.  It refers to the ribosomal translation table of codon-->amino acid (for example, AUG-->Met).  I think there actually are some variations, but it's the same in most familiar organisms.\n\nAt the molecular level, proteins evolve a few mutations at a time.  If a gene acquired too many mutations at once, the protein product would almost certainly no longer be functional.  What would happen if you were to change the genetic code in an organism?  You would have widespread mutations in almost every single protein in the organism.  What are the odds that the new organism would be capable of surviving?  Very, very low.\n\nThe basic principle is that genes that are absolutely critical for life evolve the slowest.  Thus, the genetic code has not changed as much as other things.
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The Rhesis protein marker was first discovered in Rhesis monkeys on their red cells. That's where the name came from. It wasn't until later that they discovered the same protein cluster was present on some human blood cells.\nThe similarities probably stem back from before primates evolved into man. You will find many similar protiens in monkeys to those in humans, just as you will find the same mechanisms for constructing proteins from DNA in every living cell.\n\nBelieve what you will about Adam & Eve.
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Bacteria appeared on earth between 3.4 and 4 billion years ago. Precambrian evidence of filamentous bacteria-like structures, found making up fossilized sediments called stromalites, has been discovered in Australia and southern Africa. These fossils date back between 3.4 and 3.5 billion years old. Environmental conditions of earth 4 billion years ago were much different than those of today. It has been theorized that the atmosphere was a reducing atmosphere with intense lightning, tremendous volcanic activity, very little oxygen, intense ultraviolet radiation, and meteorite bombardment. These conditions made it impossible for any type of aerobic life to exist. The first cells may have originated by chemical evolution in an anaerobic environment.\n\nAbiotic Synthesis Theory of Life: A.I.Oparin postulated, in the 1920's, that primitive earth with its reducing atmosphere favored chemical reactions that produced simple monomers that eventually formed complex organic compounds necessary for life. Stanley Miller and Harold Urey tested this hypothesis by building an apparatus to simulate the conditions of the earth at that time.\nTheir experiments produced 20 amino acids and other organic compounds including: ATP, lipids, some sugars, and the bases of RNA and DNA. The main problem of organic synthesis is how did these molecules develop without the aid of enzymes to speed up the reactions? Sidney Fox, of the University of Miami, dripped a dilute solution of organic monomers onto hot sand, clay , and rock. The water vaporized and left behind polypeptides he called proteinoids. Clay was abundant in prebiotic earth. Clay has the ability to act as a substrate for this type of chemical reaction. The charged sites on the clay attracted monomers in such concentrations to bring them into close proximity for chemical binding. Once these organic compounds were produced, aggregates of these proteinoids self-assembled into small spheres called protobionts. These small spheres were capable of osmotic swelling and shrinking and even able to produce a membrane potential.\n\nRNA the first Genetic Material: Evidence to support the idea that RNA was the first genetic material includes: short polymers of self-replicating RNA have been abiotically produced in a test tube without enzymes. RNA has the ability to act as a catalyst to help make mRNA, tRNA or rRNA. The RNA folding is unique depending on its sequence. This along with mutations, creates a variety of closely related molecules. Through chance this self-replicating material was captured by the protobionts and the entire structure developed under the guide of natural selection.\n\nOther Origin Theories:\n\nPanspermia. Extraterrestrial organic compounds located on the surface of meteorites could well have contributed to the pool of material found on prebiotic earth. Modern meteorites have given up specimens of simple organic compounds such as amino acids.\n\nSome researchers believe that life began on the sea floor away from the harsh surface environments. The discovery of deep sea vents showed the scientific community that the materials needed for life to begin were present away from the harsh surface.\n\nJulius Rebek produced a simple organic molecule in 1991 that served as a template for self-replication. This discovery suggests that RNA was too complex to have come first and a much simpler self-replicating molecule preceded it.
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Genetic code,teeth, hair, claws, brains. reproduction: color, smell, size, shape, power.Good Luck!
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Perhaps the most famous of these experiments is called the Miller-Urey experiment. Using water, methane, ammonia, and hydrogen to simulate primordial earth, and a little electrical coaxing, Miller managed to form 13 of the 21 amino acids organisms use to build proteins, and nucleic acids, mostly in the form of adenine.\n\nThere are some caveats, whether this is actually the composition of the primordial soup has been called into question, and the presence of some molecules, oxygen for example, ceased all biological molecules from forming. We really don't know what the environment was, but the important thing to take away from the experiment is that it's absolutely possible for organic molecules to spring from a random collection of chemicals.\n\nOpponents of evolution like to use the idea of a typewriter factory exploding and forming a dictionary as an allegory for spontaneous creation of a cell. For a fully formed cell to be produced spontaneously certainly is impossible, one of the leading hypothosises is that, as with everything else in evolution, it started in steps, the explosion at the typewriter factory didn't for a dictionary, it formed a word. The first form of life was probably little else than some RNA molecule that managed to replicate, more advanced structures took more time to develop. Interestingly enough, it's now thought that mitochondria were an ancient bacteria that formed a symbiotic relationship with larger cells, a relationship that was so successful, all future life was based on it, this is why they still retain their own genetic information.
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1)That start codon AUG (methionine)\n2) UGG Tryptophan\n\nThose are the only two. All other amino acids have at least two base codes for them and in lots of cases even 4. These codes i have given are mRNA codons.
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Intelligent Design answer:  God created the yeast and stainless steel and they evolved into the bread and knife.
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random mutation, originating from unicelled organisms, which spontaneously formed from organic molecules, which formed naturally due to earths early conditions. this all took really long.
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Several billion years ago, the first simple amino acids formed crude proteins and RNA to act as simple genetic coding. Over time, these nondescript organisms evolved into bacteria, then photosynthesizing bacteria. Eventually they evolved into simple invertebrates capable of sexual reproduction, and through tweaking of the ovulatory cycle, were able to lay fertilized eggs outside of their body. These invertebrates became fish, then amphibians, then reptiles, then birds. From those birds evolved the ancestor of the chicken which after 4 billion years of evolution was already capable of laying eggs.\n\nThe end.
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DNA, RNA, PNA; stepping backwards in time\n\nAll life on earth appears to share the same origins; except for a few very simple forms,  the business of replication is currently coded on the famous deoxyribonucleic acid (DNA) molecule, a genotype of great length,  but surprisingly simple structure. The work of transforming the information stored in DNA into the machinery of life is currently carried out by various forms of ribonucleic acid, RNA.   We try to find answers to the mystery of how this all came about by asking questions:\n\nRibonucleic Acid - RNA and its precursors\n\nQ) When did DNA enter the picture and under what chemical circumstances did it develop? \n\nA) There is considerable evidence that there was a period of time on Earth called the RNA world. In this world life existed as RNA as both phenotype and genotype. The RNA life form could have been a single naked strand, a collection of RNAs or RNA accompanied by a suite of cofactors (e.g. peptides, membranes, mineral surfaces, etc.). This process has not yet been fully elaborated, but is at the heart of the field of molecular biology and chemistry. \n\nThe reasons it is believed that there was an RNA world is summarized by NSCORT's Gerald Joyce in the journal Nature, Vol. 338 (1989) pp. 217-224. But it boils down to the following seven reasons: \n\nRNA has a template structure (i.e. Watson/Crick). \nRNA has catalytic properties (the ribozymes of Cech and many others). \nRNA appears in various presumably ancient cellular processes (i.e. ribosome, primer for DNA, etc.). \nRibonucleotides are components of many coenzymes (e.g. CoA, NADH, etc.). \nThe biosynthesis of histidine is uses ATP and PRPP. \nThe biosynthesis of deoxynucleotides is from ribonucleotide diphosphates. \nThe biosynthesis of dTMP is from dUMP. \nSince the RNA in the RNA world is alive, it is assumed that RNA evolved into DNA through some sort of genetic takeover event. In other words, RNA enzymes made DNA, which replaced it in the genome. Proteins were added into the mix at some point. This has never been explained in detail. \n\nThe problem is where did RNA come from? It is a VERY complex and delicate molecule. Some of the problems with RNA are discussed by Antonio Lazcano and Stanley Miller in the journal Cell, Vol. 85 (1996) pp. 793-798. In short, here is the problem: \n\n Ribose is hard to make prebiotically, is in equilibrium with the various anomeric forms, has numerous chiral centers, and decomposes very fast. \n It is very hard to make nucleosides prebiotically. \n It is very hard to prebiotically phosphorylate things (nucleosides). \n It is hard to polymerize activated NTPs with information and reasonable fidelity in a 3’-5’ manner (2’-5’ is more favorable). \n\nIt has thus been assumed that there was a much simpler informational macromolecule than RNA. It has been dubbed preRNA (or pre-RNA). This molecule may have been achiral and may have used bases other than AUGC. An example of an alternative backbone is PNA (P.E. Nielsen (1993) Origins of Life and Evolution of the Biosphere 23:323-327.) Some alternative bases are described by M.P. Robertson and S.L. Miller (1995) Science 268:702-705 and V.M. Kolb, J.P. Dworkin, and S.L. Miller (1994) Journal of Molecular Evolution 38:549-557. PreRNA is alive and its enzymes (prenozymes?) would be able to make the RNA which would replace it. The preRNA may have assembled from the prebiotic environment, or there may have been pre-preRNA around to help. \n\nNow, why couldn’t DNA have been made by preRNA? The 5 of the 7 reasons for the RNA world listed above are based on MODERN biochemistry and reasons 1 and 2 apply to DNA as well as to RNA. Much happened between the origin of life and the last common ancestor, and it is hard to accept extrapolations across such an immense time span.  There are some chemical reasons 2-deoxyribose might be a more likely candidate than ribose as well. \n\nThus to finally answer the question, DNA entered the sc
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The earliest evidence of nucleic acids was 1869, when Friedreich Meischer isolated the phosphate-containing acid from a cell nucleus.\n\nIn the 1930s/40s, Edwin Chargaff discovered the A-T, C-G pairings\nand finally in 40s/50s Rosalind Franklin identified the helix structure.
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Origins of life were initially suspcted to be of creation from God.\nThen the Theory of Evolution kicked in, suggesting all life came from a single cell.\nNow life came from a stone that banged into earth 4 billion years ago.\nBut are any of them true if we keep finding more truths. If breakthroughs always happen, wouldn't there be an endless amount of breakthroughs? So what we all know now is not the truth?\n\nThe origins of life on earth?\nDon't even think about it.
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There is no real model yet for the origin of life. However a number of discoveries have been made concerning the origin of molecular and cellular components that are necessary for life on earth:\n\n1. Conditions that existed 4.5x10^9 years ago result in the creation of certain basic small molecules of life, such as amino acids. This was demonstrated in the Urey-Miller experiment in the 50s.\n\n2. Fat molecules can organise spontaneously into layers which form the basis of cell membranes.\n\n3. Amino acids polymerize spontaneously into random RNA molecules.\n\n4. The resulting molecule soup will compete for resources, by which I mean smaller molecules, to be able to grow further. Therefore there will be selection pressures for efficiency and diversity which will favour those macromolecules that can reproduces themselves or part of themselves most quickly and efficiently.\n\n5. Thus evolution begins: once certain molecules are formed in the soup that can reproduce itself partly, they will soon dominate in the mix. In the next step the *better* ones among those will be selected and so on.\n\nTo summarize:\nWhen: between 4.5 and 2.5 billion years ago\nWhere: in water ponds at the surface of the earth\nWhy: any mixture of organic molecules will change into a mix of more complex molecules by polymerization\nHow: Selective pressure will favour those molecules that react faster and more efficient.
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This goes to the core of biological and evolutionary theory.\n\nDNA is elements arranged into nucleic acid molecules, arranged in a code (see first link). This code is directly used by a couple of RNA molecules to build protein molecules, ie enzymes (see link two).\n\nProtein molecules make up most of our body structure themselves, but for other parts (made from other molecules - which are combinations of elements), enzymes are used to arrange the correct structure.
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http://www.talkorigins.org/indexcc/CB/CB928_1.html\nhttp://www.talkorigins.org/indexcc/CB/CB928.html\n\nSome brief information there. More explained in Origin of Species for example.