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Is the Chemical Origin of Life (Abiogenesis) a Realistic Scenario?

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us look at the origin of life. There are only two possibilities for the existence of life:

1.Spontaneous assembly of life from chemicals
2.There is a Creator who designed biological systems

If you deny the existence of a Creator, scientific studies demonstrate that you must believe each of the following things about the origin of life:

Scientific Facts

Solution, you must;

Homochirality somehow arose in the sugars and amino acids of prebiotic soups, although there is no mechanism by which this can occur and is, in fact, prohibited by the second law of thermodynamics (law of entropy).

reject the second law of thermodynamics

Chemical reactions in prebiotic soups produce other sugars that prevent RNA and DNA replication.

discard chemistry data, accept knowledge gaps ("promissory materialism")

Pyrimidine nucleosides (cytosine and uracil) do not form under prebiotic conditions and only purine (adenine and guanine) nucleosides are found in carbonaceous meteorites (i.e., pyrimidine nucleosides don't form in outer space either).

discard chemistry data, accept knowledge gaps ("promissory materialism")

Even if a method for formation of pyrimidine nucleosides could be found, the combination of nucleosides with phosphate under prebiotic conditions produces not only nucleotides, but other products which interfere with RNA polymerization and replication.

discard chemistry data, accept knowledge gaps ("promissory materialism")

Purine and pyrimidine nucleotides (nucleosides combined with phosphate groups) do not form under prebiotic conditions.

discard chemistry data, accept knowledge gaps ("promissory materialism")

Neither RNA nor DNA can be synthesized in the absence of enzymes. In theory, an RNA replicase could exist and code for its own replication. The first synthesized RNA replicase was four times longer than any RNA that could form spontaneously. In addition, it was able to replicate only 16 base pairs at most, so it couldn't even replicate itself.

accept knowledge gaps ("promissory materialism")

Enzymes cannot be synthesized in the absence of RNA and ribosomes.

accept knowledge gaps ("promissory materialism")

Nucleosides and amino acids cannot form in the presence of oxygen, which is now known to have been present on the earth for at least 4.3 billion years ago, although life arose at least ~3.5 billion years ago.

discard geological data, discard chemistry data

Adenine synthesis requires unreasonable HCN concentrations. Adenine deaminates with a half-life of 80 years (at 37°C, pH 7). Therefore, adenine would never accumulate in any kind of "prebiotic soup." The adenine-uracil interaction is weak and nonspecific, and, therefore, would never be expected to function in any specific recognition scheme under the chaotic conditions of a "prebiotic soup."

discard chemistry data

Cytosine has never been found in any meteorites nor is it produced in electric spark discharge experiments using simulated "early earth atmosphere." All possible intermediates suffer severe problems. Cytosine deaminates with an estimated half-life of 340 years, so would not be expected to accumulate over time. Ultraviolet light on the early earth would quickly convert cytosine to its photohydrate and cyclobutane photodimers (which rapidly deaminate).

discard geological data, discard chemistry data

Mixture of amino acids the Murchison meteorite show that there are many classes of prebiotic substances that would disrupt the necessary structural regularity of any RNA-like replicator. Metabolic replicators suffer from a lack of an ability to evolve, since they do not mutate.

discard chemistry data

The most common abiogenesis theories claim that life arose at hydrothermal vents in the ocean. However, recent studies show that polymerization of the molecules necessary for cell membrane assembly cannot occur in salt water. Other studies show that the early oceans were at least twice as salty as they are now.

presume that life arose in freshwater ponds (even though the earth had very little land mass), using some unknown mechanism.

Comparison of the dates of meteor impacts on the moon, Mercury, and Mars indicate that at least 30 catastrophic meteor impacts must have occurred on the earth from 3.8 to 3.5 billion years ago. These impacts were of such large size that the energy released would have vaporized the entirety of the earth's oceans, destroying all life.

presume that life spontaneously arose by chance at least 30 separate times, each within a period of ~10 million years

Complex bacterial life (oxygenic photosynthesis) had appeared by 3.7 billion years ago, leaving virtually no time for prebiotics to have evolved into the first life forms.

discard evidence

New Theories

New theories, such as assembly of biomolecules on mineral surfaces, are constantly being proposed to attempt to get around the problems associated with the spontaneous origin of life. However, even if you put purified chemicals together (which can't be synthesized prebiotically), you can get polymers only up to 50 mer (obviously not enough for life) (4). Therefore, none of these theories has been able to get around the fundamental chemical problems required for life to have begun on the Earth. Some quotes from evolutionists are cited below:

"It's a very long leap from [mineral] surface chemistry to a living cell." Norman Pace (evolutionary biologist, University of California, Berkeley).

"On theoretical grounds, however, it [mineral clay synthesis] seems implausible. Structural irregularities in clay that were complicated enough to set the stage for the emergence of RNA probably would not be amenable to accurate self-replication." (Leslie Orgel)

'There is now overwhelmingly strong evidence, both statistical and paleontological, that life could not have been started on Earth by a series of random chemical reactions.... There simply was not enough time... to get life going." Niles Eldridge (paleontologist at the American Museum of Natural History).

"There is no agreement on the extent to which metabolism could develop independently of a genetic material. In my opinion, there is no basis in known chemistry for the belief that long sequences of reactions can organize spontaneously -- and every reason to believe that they cannot. The problem of achieving sufficient specificity, whether in aqueous solution or on the surface of a mineral, is so severe that the chance of closing a cycle of reactions as complex as the reverse citric acid cycle, for example, is negligible." Leslie Orgel, 1998 (The Salk Institute for Biological Studies).

Prebiotic chemistry would produce a wealth of biomolecules from non living precursors. But the wealth soon became overwhelming, with the "prebiotic soups" having the chemical complexity of asphalt (useful, perhaps, for paving roads but not particularly promising as a wellspring for life). Classical prebiotic chemistry not only failed to constrain the contents of the prebiotic soup, but also raised a new paradox: How could life (or any organized chemical process) emerge from such a mess? Searches of quadrillions of randomly generated RNA sequences have failed to yield a spontaneous RNA replicator. Steven A. Benner, 1999 (professor of Chemistry at the University of Florida).

Even origin of life researchers are now admitting that getting the basic building blocks for an RNA world is virtually impossible:

G. F. Joyce and L. E. Orgel lead us into the RNA world with a description of the difficulties in achieving the direct synthesis of nucleosides and nucleotides from prebiotic precursors and conclude that the de novo appearance of oligonucleotides on primitive Earth amounts to a "near miracle" W. Keller, 1999.

pRNA

Researchers are now examining alternative, simpler possible genetic molecules, such as pyranosyl-RNAs (pRNAs) that pair up in double helices. However, it seems unlikely that these pRNAs could have been a source of genetic material in early life forms. Pairs of complementary pRNAs form double helices that are structurally very different from those formed by DNA and RNA. According to Leslie Orgel:

"Consequently, pRNAs and RNAs are not able to form duplexes with each other, which would preclude exchange of information between these two molecules, suggesting that pRNAs are unlikely to have been the genetic material that preceded RNA." Leslie Orgel, 2000.

TNA

Recently, researchers have synthesized threose-based nucleic acid (TNA) as potential precursors of RNA and DNA (since it is obvious that RNA and DNA could not form spontaneously on primitive earth). Researchers have found that complementary TNAs form double helices among themselves and even with complementary RNAs and DNAs.

How could a primitive organism that used TNA as its genetic material switch to RNA? There are two potential mechanisms, both of which suffer major, almost certainly fatal, problems.

In one mechanism, a TNA-based primitive organism would have synthesized RNAs for a purpose other than replication, such as a means to inhibit TNA synthesis in a competing organism. Under such a scenario, RNA replication would have evolved independently of TNA replication and ultimately took over as the means by which cells reproduce themselves.

However, since the two genetic systems never interacted no useful genetic information would have been transferred from TNA to RNA. It is unclear how the original TNA replication system could have been turned off, or the more important problem of how a complete RNA genetic system could have evolved in the absence of natural selection.

In the alternative mechanism, RNA bases were at first substituted randomly a few at a time in TNA sequences until the proportion of RNA components increased over time from almost zero to 100%. The information present originally in the TNA sequence was, at least in part, preserved in the final RNA sequence.

However, this theory suffers the major drawback that the introduction of a substantial number of RNA bases at random would almost certainly destroy the catalytic function of any particular TNA sequence (a fatal "mutation") in addition to probably preventing replication of TNA, rendering evolved TNA sequences useless.

Hydrothermal vents

Undersea vents at geologically active locations on the sea floor have been cited as a possible source of energy bearing chemicals that could have provided the necessary conditions to foster the origin of life on earth. Accordingly, the Archaea present in modern day hydrothermal vents might represent descendants from these earliest life forms. However, new research shows that these Archaea probably originated from mesophiles, adapting to a thermophilic lifestyle. The extensive biochemical modifications necessary for such an adaptation, in addition to the genetic data, make it unlikely that Archaea could have originated at hydrothermal vents.

Conclusion

As can be seen from the above table and information, the atheist's position is becoming more extreme and less reasonable as more knowledge is gained through scientific studies. Atheists are becoming desperate and are now offering $1 million for an explanation that "corresponds to empirical biochemical and thermodynamic reality, and be published in a well-respected, peer-reviewed science journal(s)."

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