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Origin of Life and Consciousness - Physical View

by Pythagorean
Tags: consciousness, life, origin, physical, view
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Pythagorean
#1
Aug28-07, 03:51 AM
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Could one say that the origin of life came about when a set of particles arranged in the right way were tipped into a sort of energy equilibrium that jiggled things back and forth, in obedience to physical laws (modern physical laws of course)

And as this interaction of physical laws become more complex (where we study the trends of their overall behavior: chemistry, biochemistry, biology, etc.) they eventually led to organisms that interact, not solely on a biochemical level but at a macro-level too, perceiving, processing, and interacting on a level of general summary of all the micro interactions (what we call consciousness).

I'm curious, how did this transition, between being a little chemical interaction factory (a single cell and its organelles) to a large-scale physical interaction machine (a creature with organs) occur?
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jim mcnamara
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Aug28-07, 09:16 AM
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I can't answer paragraphs I & II.

III: Mostly the development of eukaryotic organisms during the Pre-Cambrian in the presence of an oxygen atmosphere. Eurkaryotic cells arise out of several simpler cells "merging" into another cell; taking over specific jobs. The mitochondrion is the best example. It has it's own DNA. It handles cell respiration - it fuels the rest of the cell. Mitochondrial activity requires higher levels of atmospheric/ambient oxygen. Chloroplasts are another good example.

Basically it required that the atmosphere became oxidizing, and cells became able to thrive in oxygen. Early protobacteria (archeabacteria) largely exist today only in anerobic environments or in very extreme envrionments like hot springs.

Microbiologists have known for 50 years that unrelated species of procaryotic bacteria can exchange DNA. And there are examples of multispecies globs of these guys growing in environments where one single species would fail. When I was current in this stuff, there was a big hunt on to see if a sort of 'halfway' organelle/symbiont could be found in procaryotes. Several were identified.
Pythagorean
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Aug28-07, 02:59 PM
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thank you for your reply, jim.

I understand why you wouldn't want to answer I & II.

I've heard a bit about mitochondria when discussing this before. When you speak of cells "merging" together, the description I generally hear is that mitochondria was thought to once be a sort of virus, but ended up forming a symbiotic relationship with many of the cells it "invaded". The two cells now "merged" took on different properties than either cell alone, because the mitochondria was able to produce energy must faster.

Basically it required that the atmosphere became oxidizing, and cells became able to thrive in oxygen. Early protobacteria (archeabacteria) largely exist today only in anerobic environments or in very extreme envrionments like hot springs.
what is "it"? The actual merging of the some primitive cell and mitochondria? Or the transition from small micro-interaction to macro-interaction?

BoomBoom
#4
Aug28-07, 03:50 PM
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Origin of Life and Consciousness - Physical View

Quote Quote by Pythagorean View Post
the description I generally hear is that mitochondria was thought to once be a sort of virus, but ended up forming a symbiotic relationship with many of the cells it "invaded". The two cells now "merged" took on different properties than either cell alone, because the mitochondria was able to produce energy must faster.
I would say bacteria and not virus. I suppose it could be either way...either the mitochondria invaded a cell or the cell devoured the mitochondria. Whichever way though, the symbiotic nature of their respective biochemistry is advantagious to both. Mitochondria love the oxygen our cells provide and our cells love the ATP that mitochondria provide as a waste product.

On a macro scale we also have bacteria that live within our digestive systems as well.
Pythagorean
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Aug28-07, 05:22 PM
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Quote Quote by BoomBoom View Post
I would say bacteria and not virus. I suppose it could be either way...either the mitochondria invaded a cell or the cell devoured the mitochondria. Whichever way though, the symbiotic nature of their respective biochemistry is advantagious to both. Mitochondria love the oxygen our cells provide and our cells love the ATP that mitochondria provide as a waste product.

On a macro scale we also have bacteria that live within our digestive systems as well.
and by love you mean it stimulates activity in the respective cells?
jim mcnamara
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Aug29-07, 09:20 AM
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What is "it" - it = chemical process (involving cyctochrome C) which is "toxified" by things like cyanide and some other molecules found in the early reducing atmosphere.
Moridin
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Aug29-07, 01:55 PM
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Some theoretical models suggests that the first primitive replicating molecule arose by that kind of natural experiments, assembled by the laws of chemistry and split by radiation somewhere between the formation of the earth and the first known lifeforms. According to the models, natural selection most likely took hold afterwards, as the molecules that reproduced better made more copies of itself.
BoomBoom
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Aug29-07, 02:24 PM
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Quote Quote by Pythagorean View Post
and by love you mean it stimulates activity in the respective cells?
Well, yes I reckon "love" is a very unscientific word. :)

Mitochondria feed on oxygen as an energy source and cells use their waste product (ATP) as an energy source.

Without mitochondia, I doubt the plant or animal kingdoms would have ever taken off. Although plants have a similar relationship with chloroplasts, so perhaps they could have still evolved without mitochondria.
Pythagorean
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Aug29-07, 11:07 PM
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Quote Quote by Moridin View Post
Some theoretical models suggests that the first primitive replicating molecule arose by that kind of natural experiments, assembled by the laws of chemistry and split by radiation somewhere between the formation of the earth and the first known lifeforms. According to the models, natural selection most likely took hold afterwards, as the molecules that reproduced better made more copies of itself.
In my studies on lightning, I've read that it has been speculated as a possible contributor to life.

(lightning gives off gamma radiation)
Moridin
#10
Aug30-07, 03:57 AM
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Here are some more information about the Miller-Urey experiment

http://www.ncseweb.org/icons/icon1millerurey.html
http://www.chem.duke.edu/~jds/cruise...gy/miller.html
Astronuc
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Aug30-07, 05:44 AM
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Quote Quote by Pythagorean View Post
(lightning gives off gamma radiation)
Gamma radiation originates from the nucleus or subatomic particle decay/interaction (e.g. positron annihilation), and lightning does not affect the nuclei of atoms.

Lightning is an electrical discharge, i.e. a large current of electrons, and that discharge produces optical and perhaps UV, and perhaps an exceedingly small amount of very low energy X-ray. The voltage is on the order 100 kV spread along km or so of atmosphere, so locally the V/m is not great.

The temperature of the atmosphere around the lightning discharge is about 30,000 K ( http://hypertextbook.com/facts/1999/DavidFriedman.shtml ) and with an equivalence of 11,605 K/eV, that's no more than 3 eV, which is well below the ionization energy of H (13.6 eV) which is the lowest energy X-ray. More likely, the highest energy photons would be UV.

This might be of interest - http://en.wikipedia.org/wiki/Ultraviolet

With respect to "obedience to physical laws (modern physical laws of course)", Nature is what it is and always has been, and the laws of physics are what they regardless of our understanding or knowledge of them. Certainly somehow atoms combined to form simple molecules, which interacted to form more complicated molecules, which then interacted to form complex structures like DNA, mitochondria and cells.
Pythagorean
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Aug30-07, 06:14 AM
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Quote Quote by Astronuc View Post
Gamma radiation originates from the nucleus or subatomic particle decay/interaction (e.g. positron annihilation), and lightning does not affect the nuclei of atoms.

Lightning is an electrical discharge, i.e. a large current of electrons, and that discharge produces optical and perhaps UV, and perhaps an exceedingly small amount of very low energy X-ray. The voltage is on the order 100 kV spread along km or so of atmosphere, so locally the V/m is not great.

The temperature of the atmosphere around the lightning discharge is about 30,000 K ( http://hypertextbook.com/facts/1999/DavidFriedman.shtml ) and with an equivalence of 11,605 K/eV, that's no more than 3 eV, which is well below the ionization energy of H (13.6 eV) which is the lowest energy X-ray. More likely, the highest energy photons would be UV.
Gamma radiation has been detected coming from lightning clouds. They actually seem to be associated with sprites a lot. This is a popular subject at our university, so there's a lot of Uman available in our libraries. Explanations are still theoretical for it.

From Uman:
Two kinds of runaway electrons can potentially occur:

(i) electrons that begin in the eV to 10eV energy range as a result of local breakdown and find themselves in very high electric field and relatively low particle densities, this type of runaway being termed thermal runaway, and

(ii) electrons that begin in the tens of keV or higher energy range as a result of cosmic ray collisions with air particles, in which case the electric field for runaway can be two order of magnitude lower than for thermal runaway at the same air density. In either case, in order to "run away", an electron must gain me energy from the electric field between collisions than it loses in collisions, the energy lost in a collision depending on the particle density and type and on the collision cross-section of the particles at the particular electron energy.
He also includes the references to reports that detected gamma-ray bursts.

from Lightning: Physics and Effects
Pythagorean
#13
Aug30-07, 06:16 AM
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here's an online report:

http://www.sciencedaily.com/releases...0502190314.htm
Astronuc
#14
Aug30-07, 07:31 PM
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Hmmmm. I see that people are detecting "terrestrial gamma ray flashes", or TGFs.

But in 1994, scientists using the Compton Gamma Ray Observatory satellite first detected gamma rays seemingly originating near the earth's surface. And researchers quickly found evidence that those emissions were connected to lightning, Cummer said.

Beginning in 2002, the Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI) satellite -- launched to study x-rays and gamma rays from the sun --also began detecting larger numbers of what scientists began terming terrestrial gamma ray flashes (TGFs).

Smith and Lopez were two of the four authors of a February 2005 paper in the journal Science that first described RHESSI-detected TGFs, and also corroborated those with lightning frequency data.

In the new Duke-led study, Cummer and his assistants made what he termed "very careful and continuous recordings" of lightning emissions in a targeted area over a four month period of 2004.

By analyzing those records, they identified lightning episodes they could link in time and place to TGFs recorded by RHESSI in the tropical Caribbean region. "We quantify the lightning-TGF relationship in detail and attempt to constrain the possible source mechanisms," the authors wrote in Geophysical Research Letters.
From Sciencedaily article cited by Pythagorean.

Terrestrial Gamma-Ray Flashes (TGF's) observed with BATSE
http://www.batse.msfc.nasa.gov/batse/tgf/

RHESSI Terrestrial Gamma-ray Flashes: Current Status
http://sprg.ssl.berkeley.edu/atmos/tgf/dsmith_annot.pdf

http://en.wikipedia.org/wiki/Terrest...amma-ray_flash

There is a consensus forming about the physical mechanism causing TGFs. It is presumed that TGFs occur when electrons, traveling at speeds very close to the speed of light, collide with the nuclei of atoms in the air, and release their energy in the form of gamma-rays ("bremsstrahlung"). Sometimes they also eject other electrons from the atoms at relativistic energies; thus an avalanche of these fast electrons can form, a phenomenon called "relativistic runaway breakdown" (Gurevich et al. 1992). The acceleration of the electrons is probably provided by a strong electric field, but from that point on there is considerable uncertainty.
OK, based on the brehmsstrahlung, I agree that the energetic photons are gamma radiation, as opposed to X-ray. I stand corrected.

Cool picture of a lightning discharge.
http://www.lightning.ece.ufl.edu/

Thank you, Pythagorean.
Pythagorean
#15
Aug31-07, 04:55 AM
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No problem. It's amazing how little we know about what goes on inside the lightning cloud. Uman has remarked that the lightning bolt we see strike the ground is just the "tip of the iceberg" of a lightning cloud.

Excellent picture; is that uniformity on the left side a lightning rod connecting to the stepped leader on the right?


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