ok, i dont feel like explaining the hypothesis, but ive heard that Alexander Oparin’s theory and the Stanley and Urey experiment about the origin of life can be proved wrong. In a nutshell (ive heard) we have X and Y that come together to form life. X has an A compound and Y has a B compound. (this is just for explanations sake here). so X and Y have to come together, however X cannot bond with B and Y cant bond with A. therefore, no life. can someone clear this up for me or possibly help me figure out what im talking about?
Well, just off hand, it sounds as though you are repeating stuff from an anti-evolution book or web site that rather overstates a case against Alexander Oparin’s theories regarding abiogenesis.
Dr. Oparin put forth a hypothesis that various chemicals found on Earth three and a half billion years ago might, if charged by a source of energy, have formed into the building blocks for life.
In 1953, Stanley Miller (note, Stanley is his first name) a graduate student working for Harold Urey devised an experiment to test whether Dr. Oparin’s hypothesis had any merit. He placed together a number of the chemicals it was thought might have been present on the Earth before life and jolted them with an electric charge. The result was the formation of amino acids.
People studying abiogenesis (the origin of life from non-living elements) hailed the experiment because it is known that amino acids are the basic chemicals on which life is built. (It was only a few months later than Crick and Watson were able to describe the structure of DNA.)
It should be noted that Miller’s early experiment, however promising, did not reveal the actual building blocks of life. Various opponents of Evolutionary Theory (confusing the Theory of Evolution with abiogenesis) have pointed to that “failure” as evidence (they often say proof) that life could not have arisen in that fashion.
On the other hand, Miller’s experiment was undertaken 49 years ago. It remains true that we have not yet successfully “created life,” but it is inaccurate to point to that very old experiment and claim that we have proved or disproved anything.
This still incomplete paper on the Talk Origins - Abiogenesis web page addresses some of the issues surrounding the current experiments. It also provides links to further information.
just for the record, this isnt something i just suddenly took an interest in, im learning about it in a class im talking and was wondering about it… it didnt seem logical. thanks
May I recommend the first half of “At Home in the Universe” by Stuart Kauffman for an excellent discussion of this topic in layman’s terms? I may? Thanks!
Perhaps CrAcKmOo is referring to the idea that some life processes are too complicated to have evolved? This was most famously put forward by Michael Behe in Darwin’s Black Box .
The talk.origins site is a good place to look for counterarguments - look for “intelligent design” (or ID).
I have absolutely no clue to what he was referring.
The very first thing is we don’t know what can or cannot constitute life.
Just for argument’s sake you must have this “X” and “Y” business to form life. Since both X and Y appear to be macromolecules of some kind, it is entirely possible that their parts bond together first. For example, suppose X is consisted of x and a, and b is consisted of y and b, what stops a from bonding with b first? Then a can bind with x and b with y.
Trying to parse the op. Brain hurts.
Maybe the question is about handedness (or ‘chirality’) in organic molecules. The laboratory production of simple organic molecules with a preponderance of one handedness over the other has not yet been demonstrated (so far as I know), but there is some good theoretical considerations that show that an asymmetry could develop given enough time, using chemical reactions powered by even slightly polarized light.
Please CrAcKmOo, we are fairly bright and well educated people here. Instead of using ‘x and y’ and ‘a and b’ could you please be specific in your inquiry? I assure you we will be able to understand longer words and chemisty jargon.
tomndebb wrote:
Less well known, but in my opinion just as important, were two follow-on experiments performed by Sidney W. Fox:
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By “baking” amino acids under an ultraviolet lamp, Fox discovered that the amino acids bonded together into longer-chain molecules, in much the same way that amino acids are bonded together in proteins. These molecules were not as long as conventional proteins, though, and so were dubbed proteinoids.
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By taking a lump of hot proteinoids and soaking it in a saline solution for just a few minutes, Fox discovered that little spherical membranes of proteinoids, called proteinoid microspheres, would spontaneously break off from the hot proteinoid lump and float around freely in the saline solution. These microspheres were about 1 micron across (about the size of a small coccus bacterium) and exhibited several properties normally associated with living cells, e.g. absorbing “nutrients” (other proteinoids) from their environment and splitting into two proteinoid microspheres when they got too big (a process eerily similar to mitosis). C.f. http://www.siu.edu/~protocell/.
Ding!
Maybe the op is asking about RNA world. Self-catalyzing RNA as a precursor to the DNA/ RNA/ Protein system we have now.
Or maybe not.