Is DNA a universal constant?

[ovyyus]

... almost as much fun as finding that life on Earth is the result of a DNA infested meteorite blasted here from Uranus. Although, maybe a lot of things would then make more sense :D

[rlortie]

Only to then ask, how did the DNA get on Uranus?

[Jim Williams]

Comets infected everything. That's a problem. If we do find Earth type DNA on the planets or other molecule friendly environments of the solar system, how do we know it didn't come from a common source?

I still think the solution in the future is to infect other planets with Earth life. Maybe we need think of planets being of three types, one that won't support DNA or life, one that can support it but can't originate it or one on which it can originate and be supported like Earth. I think Earth is just so DNA friendly that life did originate here.

But I still stick to my definition of life being the difference between an atom and a molecule, DNA just being the most complicated of molecules here on Earth. And the most complicated molecule of any environment being that environment's degree of life. On Earth our degree of life is DNA.

As the sun turns red giant, expanding its size to the orbit of Mars and the temporate zone of Earth type life expands to the orbit of Pluto, perhaps as we flee Earth for the outer planets we'll find them already occupied and we won't be welcome. The famous DNA Wars starting in about 6 billion years from now as the sun goes off main sequence. Why does DNA stop when strung out at only 5 1/2 feet? Why not more atoms?

[winkle]

But I still stick to my definition of life being the difference between an atom and a molecule, DNA just being the most complicated of molecules here on Earth. And the most complicated molecule of any environment being that environment's degree of life. On Earth our degree of life is DNA.

if that be true
it looks like you are saying DNA is life
every dead creature has DNA molecules aplenty where is the life
it could be that DNA is just the blueprint for a structure and has nothing to do with life
DNA can be played with but life can not be made from DNA
got to have that egg you know

Why does DNA stop when strung out at only 5 1/2 feet? Why not more atoms?

would seem to be two possabilities
# one just a pice of crap shoot luck
# two by design
ok i'll ask this question which one ?

[ovyyus]

would seem to be two possabilities
# one just a pice of crap shoot luck
# two by design
ok i'll ask this question which one ?

I think neither. Why must there only be these 2 options?

if that be true
it looks like you are saying DNA is life
every dead creature has DNA molecules aplenty where is the life

That's a pretty good question. Apparently, the cells of a persons body can remain alive and viable for a few hours after the individual is dead - ie: the cells are not dead. Where is the life of a 'dead' person when their cells are not yet dead?

http://www.msnbc.msn.com/id/18368186/si ... foreveryay

To Treat the Dead

The new science of resuscitation is changing the way doctors think about heart attacks—and death itself.

By Jerry Adler
Newsweek

May 7, 2007 issue - Consider someone who has just died of a heart attack. His organs are intact, he hasn't lost blood. All that's happened is his heart has stopped beating—the definition of "clinical death"—and his brain has shut down to conserve oxygen. But what has actually died?

As recently as 1993, when Dr. Sherwin Nuland wrote the best seller "How We Die," the conventional answer was that it was his cells that had died. The patient couldn't be revived because the tissues of his brain and heart had suffered irreversible damage from lack of oxygen. This process was understood to begin after just four or five minutes. If the patient doesn't receive cardiopulmonary resuscitation within that time, and if his heart can't be restarted soon thereafter, he is unlikely to recover. That dogma went unquestioned until researchers actually looked at oxygen-starved heart cells under a microscope. What they saw amazed them, according to Dr. Lance Becker, an authority on emergency medicine at the University of Pennsylvania. "After one hour," he says, "we couldn't see evidence the cells had died. We thought we'd done something wrong." In fact, cells cut off from their blood supply died only hours later.

But if the cells are still alive, why can't doctors revive someone who has been dead for an hour? Because once the cells have been without oxygen for more than five minutes, they die when their oxygen supply is resumed. It was that "astounding" discovery, Becker says, that led him to his post as the director of Penn's Center for Resuscitation Science, a newly created research institute operating on one of medicine's newest frontiers: treating the dead.

Biologists are still grappling with the implications of this new view of cell death—not passive extinguishment, like a candle flickering out when you cover it with a glass, but an active biochemical event triggered by "reperfusion," the resumption of oxygen supply. The research takes them deep into the machinery of the cell, to the tiny membrane-enclosed structures known as mitochondria where cellular fuel is oxidized to provide energy. Mitochondria control the process known as apoptosis, the programmed death of abnormal cells that is the body's primary defense against cancer. "It looks to us," says Becker, "as if the cellular surveillance mechanism cannot tell the difference between a cancer cell and a cell being reperfused with oxygen. Something throws the switch that makes the cell die."

With this realization came another: that standard emergency-room procedure has it exactly backward. When someone collapses on the street of cardiac arrest, if he's lucky he will receive immediate CPR, maintaining circulation until he can be revived in the hospital. But the rest will have gone 10 or 15 minutes or more without a heartbeat by the time they reach the emergency department. And then what happens? "We give them oxygen," Becker says. "We jolt the heart with the paddles, we pump in epinephrine to force it to beat, so it's taking up more oxygen." Blood-starved heart muscle is suddenly flooded with oxygen, precisely the situation that leads to cell death. Instead, Becker says, we should aim to reduce oxygen uptake, slow metabolism and adjust the blood chemistry for gradual and safe reperfusion.

Researchers are still working out how best to do this. A study at four hospitals, published last year by the University of California, showed a remarkable rate of success in treating sudden cardiac arrest with an approach that involved, among other things, a "cardioplegic" blood infusion to keep the heart in a state of suspended animation. Patients were put on a heart-lung bypass machine to maintain circulation to the brain until the heart could be safely restarted. The study involved just 34 patients, but 80 percent of them were discharged from the hospital alive. In one study of traditional methods, the figure was about 15 percent.

Becker also endorses hypothermia—lowering body temperature from 37 to 33 degrees Celsius—which appears to slow the chemical reactions touched off by reperfusion. He has developed an injectable slurry of salt and ice to cool the blood quickly that he hopes to make part of the standard emergency-response kit. "In an emergency department, you work like mad for half an hour on someone whose heart stopped, and finally someone says, 'I don't think we're going to get this guy back,' and then you just stop," Becker says. The body on the cart is dead, but its trillions of cells are all still alive. Becker wants to resolve that paradox in favor of life.

© 2007 Newsweek, Inc.

[winkle]

I think neither. Why must there only be these 2 options?

well could you explain what the other options would be

That's a pretty good question. Apparently, the cells of a persons body can remain alive and viable for a few hours after the individual is dead - ie: the cells are not dead. Where is the life of a 'dead' person when their cells are not yet dead?

http://www.msnbc.msn.com/id/18368186/si ... foreveryay

that's interesting
all i know is when you're dead you're dead and when you're not you're not
and that DNA can not on it's on bring forth or create life
so which came first the DNA or the egg

[Jim Williams]

If my reading is correct DNA is only the blueprint and not life itself. The mechanic is RNA which translates the blueprint into life. I'm sticking with my definition of life though, being the molecule with the most atoms in a given environment. It is interesting to me that DNA is 5 1/2 ft long on both sides of the equation. One, it doesn't grow longer than 5 1/2 ft, but unzips instead, forming two virtually identical DNA molecules. Two, it reaches 5 1/2 ft in the first place. I think both are true entirely for reasons explainable by physics alone.

Some scientist here at Berkeley said the purpose of a gene is to replicate itself, the vehicle, i.e., a human body for example, being incidental. I'm not sure when one animal eats another wheather all its DNA is digested. Something tells me feces is just loaded with intact DNA, but that it doesn't stand a chance from that point on anyway, returning into dust.

That heart cells live so long is just plain fascinating.

[ovyyus]

http://www.space.com/scienceastronomy/0 ... _life.html

Hot Gas in Space Mimics Life
By Ker Than
SPACE.com staff
posted: 14 August 2007


Electrically charged specks of interstellar dust organize into DNA-like double helixes and display properties normally attributed to living systems, such as evolving and reproducing, new computer simulations show.

But scientists are hesitant to call the dancing dust particles "alive," and instead say they are just another example of how difficult it is to define life.

Plasma life

The computer model, detailed in the Aug. 14 issue of the New Journal of Physics, shows what happens to microscopic dust particles when they are injected into plasma.

Plasma is the fourth state of matter along with solids, liquids and gases. While unfamiliar to most people, plasma is the most common phase of matter in the universe. It's everywhere: Stars are luminous balls of plasma, and diffuse plasma pervades the space between stars. Plasma forms when gas becomes so hot that electrons are stripped from atomic nuclei, leaving behind a soup of charged particles.

Past studies on Earth have shown that if enough particles are injected into a low-temperature plasma, they will spontaneously organize into crystal-like structures.

The new computer simulations suggest that in the gravity-free environment of space, the plasma particles will bead together to form string-like filaments that then twist into corkscrew shapes. The helical strands resemble DNA and are themselves electrically charged and attracted to one another.

The computer-modeled plasma particles can also divide to form two copies of the original structure and even "evolve" into more stable structures that are better able to survive in the plasma.

"These complex, self-organized plasma structures exhibit all the necessary properties to qualify them as candidates for inorganic living matter," said study team member V.N. Tsytovich of the Russian Academy of Science.

Is it alive?

Nevertheless, Tsytovich's colleague and study team member, Gregor Morfill of the Max Planck Institute for Extraterrestrial Physics in Garching, Germany, is hesitant to call the plasma particles alive.

"Maybe it's a question of upbringing," Morfill said in a telephone interview. "I would hesitate to call it life. The reason why we published this paper is not because we wanted to suggest this could evolve into life, but because we wanted to start the discussion ... once more of what exactly do we mean by life."

Seth Shostak, a senior astronomer at the SETI Institute in Mountain View, California, also was cautious in calling the particles alive. "The facts are, we still don't have a good definition of what 'life' is," Shostak told SPACE.com.

Shostak points out that while most high-school biology textbooks include as requirements for life the ability to metabolize and reproduce, it's easy to think of things that break these rules. Fire, for example, reproduces and metabolizes, but most people would not say it is alive; and mules, which are clearly alive, can't reproduce.

"We still stumble on what it means to be alive, and that means that these complex molecules are in a never-never land between the living and the merely reacting," Shostak added.

If the particles were considered alive though, Shostak said, it would completely overturn another common assumption about life.

"We've always assumed that life was a planetary phenomenon. Only on planets would you have the liquids thought necessary for the chemistry of life," he said. "So if you could have life in the hot gases of a star, or in the hot, interstellar gas that suffuses the space between the stars, well, not only would that be 'life as we don't know it' but it might be the most common type of life."

[winkle]

Shostak points out that while most high-school biology textbooks include as requirements for life the ability to metabolize and reproduce, it's easy to think of things that break these rules. Fire, for example, reproduces and metabolizes, but most people would not say it is alive;

and mules, which are clearly alive, can't reproduce.

that is not correct
it may not happen often but it does happen

http://origin.denverpost.com/news/ci_6464853

[Jim Williams]

In my obscure definition of life, i.e., life is a molecule, a piece of iron is nonlife, while the rust that forms on it is a beginning life form. I remember seeing photos from the sky of Indians bathing in the Ganges river and how much they resembled how rust formed on a slab of iron I had. No proof of anything, but it was remarkable to me how similar they looked.

That is just a fascinating article about computer generated plasma DNA possibilities. I'll remember it for quite some time. Maybe interstellar DNA just needs a planet on which to grow, not unlike how viruses need to take over a cell in order to duplicate. Regardless, I remain convinced that DNA molecules themselves, wheather in a plasma or in liquid water planets spontaeously generate, with all the lesser molecules like gene structures also forming into complete cells, say in Earth's oceans for example.

Where else but on a PPM discussion board would anyone find reason to post an article about mules? Thanks, fasicnating stuff.