According to evolution theory ,how was the first DNA formed?
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Charles Darwin proposed that the first proteins evolved from non-living matter. But how did this happen? Firstly, the earth was not the same today as it was 3 to 4 billion years ago when the first organic compounds where being formed. The early atmosphere was too hot for oxygen (O), nitrogen (N), and other elements to exist alone, as they do today. These elements combined to form methane (CH4), ammonia (NH3), water vapor (H2O), hydrogen sulfide (formula), hydrogen molecules (H2), etc. These where all, and thus the early atmosphere was called a 'reducing atmosphere'. Further, as there was no free oxygen to form an ozone (O3) layer to protect the earth from the harsh ultra-violet radiation (UV Rays) from the sun. Also, there where incredibly violent electrical storms, which where more violent than any which occur today. \n\nIn 1924 Alexander Oparin hypothesized that organic compounds where formed in the early earth when the high energy provided by UV Rays, and storms, caused different molecules to react, and create new organic compounds, such as Amino Acids DNA, and RNA.
86425
The first chicken was hatched from an egg of something that was not quite a chicken. That's evolution :-)
221223
While I believe in an intelligent design, (for scientific purposes) the first cell was believed to come about through chemical evolution.  Supposedly, our world use to be a rather hostile environment, composed of very few elements.  Through some process, these elements reacted together and formed chemical compounds, specifically nucleic acids, or genetic material.  As the environment continued to change, more chemicals were formed (amino acids, etc.) and began interacting until eventually, they organized in such a fashion they formed a cellular organism, capable of reproducing itself.  From this cell, more cells were produced, leading to evolutionary changes between the cells, eventually leading to different types/kinds of cells, and ultimately different organisms.  So while cells do come from other cells, supposedly there was a "first cell".\n\nI'm not sure if this makes sense or even answers the question.........?
1108483
Deoxyribonucleic acid (DNA) is a nucleic acid —usually in the form of a double helix— that contains the genetic instructions specifying the biological development of all cellular forms of life, and many viruses. DNA is a long polymer of nucleotides (a polynucleotide) and encodes the sequence of the amino acid residues in proteins using the genetic code, a triplet code of nucleotides. DNA is thought to date back to between approximately 3.5 to 4.6 billion years ago [1].\n\nIn complex eukaryotic cells such as those from plants, animals, fungi and protists, most of the DNA is located in the cell nucleus. By contrast, in simpler cells called prokaryotes, including the eubacteria and archaea, DNA is not separated from the cytoplasm by a nuclear envelope. The cellular organelles known as chloroplasts and mitochondria also carry DNA.\n\nDNA is often referred to as the molecule of heredity as it is responsible for the genetic propagation of most inherited traits. In humans, these traits can range from hair color to disease susceptibility. During cell division, DNA is replicated and can be transmitted to offspring during reproduction. Lineage studies can be done based on the facts that the mitochondrial DNA only comes from the mother, and the male Y chromosome only comes from the father.\n\nEvery person's DNA, their genome, is inherited from both parents. The mother's mitochondrial DNA together with twenty-three chromosomes from each parent combine to form the genome of a zygote, the fertilized egg. As a result, with certain exceptions such as red blood cells, most human cells contain 23 pairs of chromosomes, together with mitochondrial DNA inherited from the mother.
219004
In my opinon.. the first chicken egg pre-dated the first chicken.\n\nAt one point there was a creature that was only one mutation away from being it chicken - it was ALMOST a chicken.  It mutated and then laid an egg that expressed the mutation by hatching into the worlds first full fledged chicken.\n\nThis question can be argued so many ways...  of course, if you don't accept the theory of evolution, my arguement is meaningless.
706107
The endosymbiotic theory states that higher order organisms (read eukaryotes) developed over time as a symbiotic relationship developed between earlier prokaryotic organisms. This is most routinely applied to the conceptual arrangements surrounding chloroplasts and plant cells and mitochondria and all cells. The theory states that a free living organism in the prokaryotic lineage developed a capacity for absorbing another energy producing type of organism. The interaction was able to provide a survival advantage for the newly formed organism and thus was maintained. Mitochondria do contain their own genome, but their array of required proteins come from both the mitochondrial genome and the nuclear genome.
1109658
reverse evolution\n\nit began with cain
914670
Yes, this is assumed to be the case, and much has been written on it, but little is known in detail. The first life form, or the ancestor of life, depending on how you define things, is generally presumed to have been a single molecule or small group of molecules capable of doing two things: 1 Catalyze reactions in its environment that lead to a copy of itself being assembled and 2 be nontrivial enough in structure so that slight changes can result in mutations still capable of performing number 1. 1 has been achieved in highly specialized environments, but not 2. To be a candidate for the first natural life, 1 would have to be possible in the natural environment of the time. Until such is found, there will remain a gap in our understanding that some will prefer to explain by the action of their God of the Gaps.\n\nI've listed one book that discusses such speculations.
478857
While the echoes of Darwin's book The Origin of Species reverberated, an Austrian botanist by the name of Gregor Mendel discovered the laws of inheritance in 1865. Not much heard of until the end of the century, Mendel's discovery gained great importance in the early 1900s. This was the birth of the science of genetics. Somewhat later, the structure of the genes and the chromosomes was discovered. The discovery, in the 1950s, of the structure of the DNA molecule that incorporates genetic information threw the theory of evolution into a great crisis. The reason was the incredible complexity of life and the invalidity of the evolutionary mechanisms proposed by Darwin. \nThese developments ought to have resulted in Darwin's theory being banished to the dustbin of history. However, it was not, because certain circles insisted on revising, renewing, and elevating the theory to a scientific platform. These efforts gain meaning only if we realise that behind the theory lay ideological intentions rather than scientific concerns. \nThe Desperate Efforts of Neo-Darwinism\nDarwin's theory entered into a deep crisis because of the laws of genetics discovered in the first quarter of the 20th century. Nevertheless, a group of scientists who were determined to remain loyal to Darwin endeavoured to come up with solutions. They came together in a meeting organised by the Geological Society of America in 1941. Geneticists such as G. Ledyard Stebbins and Theodosius Dobzhansky, zoologists such as Ernst Mayr and Julian Huxley, paleontologists such as George Gaylord Simpson and Glenn L. Jepsen, and mathematical geneticists such as Ronald Fisher and Sewall Right, after long discussions, finally agreed on ways to "patch up" Darwinism. \nThis cadre focused on the question of the origin of the advantageous variations that supposedly caused living organisms to evolve-an issue that Darwin himself was unable to explain but simply tried to side-step by depending on Lamarck. The idea was now "random mutations". They named this new theory "The Modern Synthetic Evolution Theory", which was formulated by adding the concept of mutation to Darwin's natural selection thesis. In a short time, this theory came to be known as "neo-Darwinism" and those who put forward the theory were called "neo-Darwinists".\nThe following decades were to become an era of desperate attempts to prove neo-Darwinism. It was already known that mutations-or "accidents" -that took place in the genes of living organisms were always harmful. Neo-Darwinists tried to establish a case for "advantageous mutation" by carrying out thousands of mutation experiments. All their attempts ended in complete failure.\nWhy Cannot Natural Selection Explain Complexity?\nThere is nothing that natural selection contributes to the theory of evolution, because this mechanism can never increase or improve the genetic information of a species. Neither can it transform one species into another: a starfish into a fish, a fish into a frog, a frog into a crocodile, or a crocodile into a bird. The biggest defender of punctuated equilibrium, Stephen Jay Gould, refers to this impasse of natural selection as follows; \nThe essence of Darwinism lies in a single phrase: natural selection is the creative force of evolutionary change. No one denies that selection will play a negative role in eliminating the unfit. Darwinian theories require that it create the fit as well.16\nAnother of the misleading methods that evolutionists employ on the issue of natural selection is their effort to present this mechanism as conscious. However, natural selection has no consciousness. It does not possess a will that can decide what is good and what is bad for living things. As a result, one cannot explain biological systems and organs that possess the feature of "irreducible complexity" by natural selection. These systems and organs are comp
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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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History of the concept: Aristotle, Pasteur, Darwin, Oparin\n\nFrom its first formulation by Aristotle in the 4th century BC it was an article of both common and learned belief, at least in Europe, that complex living organisms arose spontaneously from non-living matter - fleas and adult mice from dirty laundry and from piles of wheat, maggots and flies from rotting meat, aphids from drops of dew. Life, in short, came about by spontaneous generation, or abiogenesis. Holes began to be knocked in Aristotle's dictum by early biologists in the 18th century, but not until the meticulous experiments of Louis Pasteur in 1862 was it finally established that a truly sterile medium would remain forever sterile, and that complex living organisms come only from other complex living organisms. The "Law of Biogenesis", (omne vivum ex ovo or "all life from an egg") based on his work is now a cornerstone of modern biology.\n\nThe modern science of abiogenesis addresses a fundamentally different question: the ultimate origin of life itself. Pasteur had proved that abiogenesis was impossible for complex organisms. Charles Darwin's theory of evolution put forward a mechanism whereby such organisms might evolve over millennia from simple forms, but it did not address the original spark, as it were, from which even simple organisms might have arisen. Darwin was aware of the problem. In a letter to J.D. Hooker of February 1, 1871, he made the suggestion that life may have begun in a "warm little pond, with all sorts of ammonia and phosphoric salts, lights, heat, electricity, etc. present, [so] that a protein compound was chemically formed ready to undergo still more complex changes". He went on to explain that "at the present day such matter would be instantly devoured or absorbed, which would not have been the case before living creatures were formed." In other words the presence of life itself prevents the spontaneous generation of simple organic compounds from occurring on Earth today - a circumstance which makes the search for the first life dependent on the laboratory.\n\nThe answer to Darwin's question was beyond the reach of the experimental science of his day, and no real progress was made during the 19th century. In 1936 Aleksandr Ivanovich Oparin, in his "The Origin of Life on Earth", demonstrated that, pace Pasteur, it was the presence of atmospheric oxygen, and other more sophisticated life-forms that prevented the chain of events that would lead to the evolution of life. Oparin argued that a "primeval soup" of organic molecules could be created in an oxygen-less atmosphere, through the action of sunlight. These, he suggested, combine in ever-more complex fashion until they are dissolved into a coacervate droplet. These droplets, he suggested, "grow" by fusion with other droplets, and "reproduce" through fission into daughter droplets, and so have a primitive metabolism in which those factors which promote "cell integrity" survive, those that don't become extinct. All modern theories of the origin of life take Oparin's ideas as a starting point.
189844
Science estimates that the first DNA forms of life were present on Earth around 3.5 billion years ago.
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Technically, and scientifically it is a theory. Theory doesn't  mean that it isn't true though, it simply means it is the most widely accepted opinion of the scientific community until someone can come along with a better theory or disprove the theory.\n\n"God created Us" is not a scientifically accepted proof against the theory of evolution. This is because without evolution DNA mutation makes no sense, even though it is a well observed phenomena.\n\nFossils also would have no explanation.\n\nAnd as a teacher, it would be best to say that it is okay to not believe every theory, because many past theorems have been proved wrong, but that he or she should maybe look into evolution a little more before casting a judgement.
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Space-filling model of a section of DNA moleculeDeoxyribonucleic acid (DNA) is a nucleic acid that contains the genetic instructions specifying the biological development of all cellular forms of life (and most viruses). DNA is a long polymer of nucleotides and encodes the sequence of the amino acid residues in proteins using the genetic code, a triplet code of nucleotides. \n\nIn complex cells (eukaryotes), such as those from plants, animals, fungi and protists, most of the DNA is located in the cell nucleus. By contrast, in simpler cells (prokaryotes) such as bacteria, DNA is not separated from the cytoplasm by a nuclear envelope. The energy-generating organelles known as chloroplasts and mitochondria also carry DNA. \n\nDNA is often referred to as the molecule of heredity as it is responsible for the genetic propagation of most inherited traits. These traits can range from hair colour to disease susceptibility. During cell division, DNA is replicated and can be transmitted to offspring during reproduction. Lineage studies can be done based on the facts that the DNA in mitochondria (mitochondrial DNA) only comes from the mother, and the male "Y" chromosome only comes from the father. \n\nEvery person's DNA is inherited from both parents. The mother's mitochondrial DNA together with twenty-three chromosomes from each parent combine to form the genome of a fertilized egg. As a result, with certain exceptions such as red blood cells, most human cells contain 23 pairs of chromosomes, together with mitochondrial DNA inherited from the mother. DNA Overview Unsolved problems in biology: Do all organisms link together to a primary source? Given a DNA sequence, what shape will the protein fold into? Given a particular desired shape, what DNA sequence will produce it? What are all the functions of the DNA? The building block of life may be a precursor to a generation of electronic devices and computers, but what are the electronic properties of DNA? Is junk DNA only molecular garbage?\nDNA Under electron microscopeThis section presents a simple (but admittedly unsophisticated) overview of DNA. \nGenes can be loosely viewed as the organism's "cookbook" or "blueprint"; \nA strand of DNA contains genes, areas that regulate genes, and areas that either have no function, or a function we do not (yet) know; \nDNA (for DeoxyriboNucleic Acid) differs from RNA by having the sugar 2-deoxyribose instead of ribose in its backbone. This is the basic chemical distinction between RNA and DNA. \nDNA is organized as two complementary strands, head-to-toe, with bonds between them that can be "unzipped" like a zipper, separating the strands; \nDNA is a chain of chemical "building blocks", called "bases", of which there are four types: these can be abbreviated A, T, C, and G, with U rarely replacing T, notably in PBS1 phage DNA; each base "pairs up" with only one other base: A+T or U, T or U+A, C+G and G+C; that is, an "A" on one strand of double-stranded DNA will "mate" properly only with a "T" or "U" on the other, complementary strand; \nBecause each strand of DNA has a directionality, the sequence order does matter: A+T is not the same as T+A, just as C+G is not the same as G+C; \nFor each given base, there is just one possible complementary base, so naming the bases on the conventionally chosen side of the strand is enough to describe the entire double-strand sequence; \nThe order of the bases along the length of the DNA is the genetic material, the sequence itself is the description for genes; \nThe cell begins DNA replication by forcibly unzipping the DNA double strand down the middle, and then recreates the "other half" of each new single strand by drowning each half in a "soup" made of the four bases. An enzyme makes a new strand by finding the correct "base" in the soup and pairing it with the or
1005721
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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"Creation" and "Evolution" are two different processes, I think.\n\nThey are easier to understand for me if I put them into different "frameworks".\n\nIf there shall be some "beginning" of every item in the world, there shall be also "Creation". But, in opposite, if we are satisfied with the idea of constant continuation - without any beginning and any end - we do not have to think this idea anymore.\n\n"Evolution" is something which can be proved everyday. I work as a microbiologist and small modifications of living creatures is very obvious for me.\n\nThere are still many open questions which can be placed between "Creation" and Evolution". One of my "favourite problem" is the beginning of DNA-based living creatures: DNA needs enzymes to be constructed, and enzymes need DNA to be produced. Which is the probability of an event where both DNA and enzymes (and such forms of them which are interconnected!) can be formed exactly in the same time? 0,00000000000000000000....%?\n\nAs a conclusion: I thrust on "Evolution" but I see also "Creation", managed by "X" (you can replace "X" by "God", "Engineer" or whatever you like). They are not alternatives for ones thinking; they have a peaceful coexistence in our world.
577209
Deoxyribonucleic acid (DNA) is a nucleic acid —usually in the form of a double helix— that contains the genetic instructions specifying the biological development of all cellular forms of life, and most viruses. DNA is a long polymer of nucleotides (a polynucleotide) and encodes the sequence of the amino acid residues in proteins using the genetic code, a triplet code of nucleotides.\n\nIn complex eukaryotic cells such as those from plants, animals, fungi and protists, most of the DNA is located in the cell nucleus. By contrast, in simpler cells called prokaryotes, including the eubacteria and archaea, DNA is not separated from the cytoplasm by a nuclear envelope. The cellular organelles known as chloroplasts and mitochondria also carry DNA.\n\nDNA is often referred to as the molecule of heredity as it is responsible for the genetic propagation of most inherited traits. In humans, these traits can range from hair colour to disease susceptibility. During cell division, DNA is replicated and can be transmitted to offspring during reproduction. Lineage studies can be done based on the facts that the mitochondrial DNA only comes from the mother, and the male Y chromosome only comes from the father.\n\nEvery person's DNA, their genome, is inherited from both parents. The mother's mitochondrial DNA together with twenty-three chromosomes from each parent combine to form the genome of a zygote, the fertilized egg. As a result, with certain exceptions such as red blood cells, most human cells contain 23 pairs of chromosomes, together with mitochondrial DNA inherited from the mother.\n\nContrary to a common misconception, the DNA is not a single molecule, but rather a pair of molecules joined by hydrogen bonds: it is organized as two complementary strands, head-to-toe, with the hydrogen bonds between them.[1] Each strand of DNA is a chain of chemical "building blocks", called nucleotides, of which there are four types: adenine (abbreviated A), cytosine (C), guanine (G) and thymine (T).[1] (Thymine should not be confused with thiamine, which is vitamin B1.) In some organisms, most notably the PBS1 phage, Uracil (U) replaces T in the organism's DNA.[2] These allowable base components of nucleic acids can be polymerized in any order giving the molecules a high degree of uniqueness.\n\nBetween the two strands, each base can only "pair up" with one single predetermined other base: A+T, T+A, C+G and G+C are the only possible combinations; that is, an "A" on one strand of double-stranded DNA will "mate" properly only with a "T" on the other, complementary strand; therefore, naming the bases on the conventionally chosen side of the strand is enough to describe the entire double-strand sequence.[1] Two nucleotides paired together are called a base pair. On rare occasions, wrong pairing can happen, when thymine goes into its enol form or cytosine goes into its imino form. The double-stranded structure of DNA provides a simple mechanism for DNA replication: the DNA double strand is first "unzipped" down the middle, and the "other half" of each new single strand is recreated by exposing each half to a mixture of the four bases. An enzyme makes a new strand by finding the correct base in the mixture and pairing it with the original strand. In this way, the base on the old strand dictates which base will be on the new strand, and the cell ends up with an extra copy of its DNA.\n\nDNA contains the genetic information that is inherited by the offspring of an organism; this information is determined by the sequence of base pairs along its length. A strand of DNA contains genes, areas that regulate genes, and areas that either have no function, or a function yet unknown. Genes can be loosely viewed as the organism's "cookbook" or "blueprint".\n\n\n\nCloning is the process of creating an identical copy of an original. A clone in the biological sen