Heredity, containment, metabolism.

  • Thread starter saltydog
  • Start date
  • Tags
    Metabolism
In summary, the Los Alamos group is attempting to simulate heredity, metabolism, and containment as follows: they are using fatty acids as a containment agent, they are using PNA (peptide nucleic acids) to create heredity, and they are using light to activate the PNA precursors and create active peptide nucleic acids. However, there is not yet sufficient evidence to suggest that this process actually produces living organisms.
  • #1

saltydog

Science Advisor
Homework Helper
1,591
3
Not sure you guys have seen or talked about this already, but I just got on-line access to New Scientist Magazine. The Feb 12 2005 issue was about creating artificial life. Here's a short summary about a Los Alamos team's attempt to do so:

The key difference between life and non-life is Darwinian evolution. This requires some sort of device, a molecule for example, to carry hereditary information. The device must have a separate identity from it's environment, that is, must be contained in some sort of container, and finally, must have an energy source: a metabolism. Thus we have the most fundamental definition of life: heredity, containment, metabolism. The Los Alamos group is attempting to simulate these three as follows:

Containment: In a word fatty-acids. You know, polar on one end, non-polar on the other. Just like real cell membranes. These form "vesicles" naturally.

Heredity: They're using PNA (peptide nucleic acids). Instead of ribose-phosphate backbone like DNA, these have protein chains to which nucleic acids are attached.

Metabolism: I quote: "The Bug will also be supplied with inactive PNA precursors bound to a photosensitive molecule. . . . when light strikes this photosensitiser, it breaks off to release the active PNA fragment."
Don't quite understand how that supplies energy at least along the lines of glycolysis, Kreb cycle, ATP synthesis, etc.

Anyway, if you're interested in prebiotic evolution, you may wish to check out this issue.
 
Biology news on Phys.org
  • #2
saltydog said:
Not sure you guys have seen or talked about this already, but I just got on-line access to New Scientist Magazine. The Feb 12 2005 issue was about creating artificial life. Here's a short summary about a Los Alamos team's attempt to do so:

The key difference between life and non-life is Darwinian evolution. This requires some sort of device, a molecule for example, to carry hereditary information. The device must have a separate identity from it's environment, that is, must be contained in some sort of container, and finally, must have an energy source: a metabolism. Thus we have the most fundamental definition of life: heredity, containment, metabolism. The Los Alamos group is attempting to simulate these three as follows:

Containment: In a word fatty-acids. You know, polar on one end, non-polar on the other. Just like real cell membranes. These form "vesicles" naturally.

Heredity: They're using PNA (peptide nucleic acids). Instead of ribose-phosphate backbone like DNA, these have protein chains to which nucleic acids are attached.

Metabolism: I quote: "The Bug will also be supplied with inactive PNA precursors bound to a photosensitive molecule. . . . when light strikes this photosensitiser, it breaks off to release the active PNA fragment."
Don't quite understand how that supplies energy at least along the lines of glycolysis, Kreb cycle, ATP synthesis, etc.

Anyway, if you're interested in prebiotic evolution, you may wish to check out this issue.

They probably won't have Krebs-style metabolisms, but necessarily they will have some mechanism for extracting free energy from the environment and deploying it usefully within the containment vesicle. That would qualify as a metabolism in the general meaning of the word.

What I like about this program is that if it succeeds the creationists will have no chance to object that they used "life to create life", since the whole chemical basis is different from existing life.
 
  • #3
It doesn't matter how strong the scientific proof against creationist arguments is. Some do not bother.
 
  • #4
Ok, I can begin to understand the metabolism: it's photosynthetic. The action of light disassociates the photosensitiser. The resulting species (free-radiacals perhaps) are unstable and thus energetic and are availabe I guess to slough-off their free energy to drive other reactions.
 
  • #5
Daevren said:
It doesn't matter how strong the scientific proof against creationist arguments is. Some do not bother.

Sure, but the more you can back them into their little box and capture the high ground of public opinion, the better. The fact that evolution for all its scientific success has not been able to do that is the reason for these perpetually recurring school issues like Kansas.
 
  • #6
selfAdjoint said:
Sure, but the more you can back them into their little box and capture the high ground of public opinion, the better. The fact that evolution for all its scientific success has not been able to do that is the reason for these perpetually recurring school issues like Kansas.

Well, I'd have to say it's not a failing on the part of Evolution but rather a fine reflection of the frailties of human intellect.
 
  • #7
Today I read they constructed reproducing little robots(nanobots?).
 
  • #8
saltydog said:
Well, I'd have to say it's not a failing on the part of Evolution but rather a fine reflection of the frailties of human intellect.

The problem is there isn't any sufficiently powerful "smoking gun' to demonstrate to the public that evolution is real. "Lucy" was the closest to what I have in mind. Creation of new life in the lab would be another. Yes that isn't technically evolution, but the public always confuses evolution with the origin of life.
 
  • #9
selfAdjoint said:
The problem is there isn't any sufficiently powerful "smoking gun' to demonstrate to the public that evolution is real. "Lucy" was the closest to what I have in mind. Creation of new life in the lab would be another. Yes that isn't technically evolution, but the public always confuses evolution with the origin of life.

Perhaps none they are willing to learn about. I think there's tons really but even if I gave some examples, (the moth story is one of my favorites), they wouldn't believe it. I'm not the best person to defend evolution as I've been out of it of late; other people perhaps here could offer some fine examples, perhaps the best we can come up with of "microevolution" by natural selection. I'm confident the list would be astounding.
 
  • #10
saltydog said:
Perhaps none they are willing to learn about. I think there's tons really but even if I gave some examples, (the moth story is one of my favorites), they wouldn't believe it. I'm not the best person to defend evolution as I've been out of it of late; other people perhaps here could offer some fine examples, perhaps the best we can come up with of "microevolution" by natural selection. I'm confident the list would be astounding.

Critics managed to smudge up the peppered moth story, so the creationist debaters can represent it as a wash, if not a phony imposture. And to reply "Wait, the critics were routed!" only elicits a scornful "Routed by whom?" and the implication that once again the evolutionists have fearfully circled the wagons. You can't debate them; you must crush them in the news. Headlines that can't be debated away.
 
  • #11
selfAdjoint said:
Critics managed to smudge up the peppered moth story, so the creationist debaters can represent it as a wash, if not a phony imposture. And to reply "Wait, the critics were routed!" only elicits a scornful "Routed by whom?" and the implication that once again the evolutionists have fearfully circled the wagons. You can't debate them; you must crush them in the news. Headlines that can't be debated away.

Alright, peppered moth. Should have taken the time to google it to get my story straight. It is a beautiful example nevertheless. There are thousands more as anyone involved in Evolutionary Biology would tell us. I am always amazed when I learn of a new one (adaptation through natural selection that is). Really I think no headlines of any metric, with due respect sir, would ever convince the creationist of their erroneous ways. We have so much more evolving to do.
 
  • #12
Problem is this.

Its easy to reject evolution because there are no mutations that 'add a new function'. Evolution doesn't do that with one mutation so its impossible to show it.

Then its easy to not understand the effect of evolution over millions of years. The human brain isn't programmed for time scales like that. And if they do manage it a little, they can always forget about natural selection and it all breaks down anyway.

As long as a creationst can't watch an organism and see it evolve they have the possibilities not to believe it is possible.

This is the 'smoking gun' most creationists ask for. They want to see a creature evolve into something totally different.
 
  • #13
Daevren said:
Problem is this.

Its easy to reject evolution because there are no mutations that 'add a new function'. Evolution doesn't do that with one mutation so its impossible to show it.

Then its easy to not understand the effect of evolution over millions of years. The human brain isn't programmed for time scales like that. And if they do manage it a little, they can always forget about natural selection and it all breaks down anyway.

As long as a creationst can't watch an organism and see it evolve they have the possibilities not to believe it is possible.

This is the 'smoking gun' most creationists ask for. They want to see a creature evolve into something totally different.

I agree I find it impossible to comprehend millions of years just like I find it incomprehensible to fathom the size of the galaxy. Why then am I so confident of evolution to the extent I shall take it and it's many implications (religous and otherwise) with me to my grave without the slightest reservation? I think history has a lot to do with it, particularly that of Medicine and Astronomy.

I have a picture . . . a nice one, middle-ages . . .wait, let me get it . . . drilling right through his head they are. And what's that funnel on his head anyway? Bacterial contamination? What bacteria? Removing the stone of folly? Poor chap. Antibiotics? Sure they had them back then. One was called "keep-your-mouth-shut-cillin". Another one was "stay-away-from-the man-with-the-funnel-on-his-head-cillin". Best you walk a straight line back then I suppose. Astronomy? Oh God, I best not get started as this is a Biology forum.

Our fragile understanding of the world changes along with our fragile selves. Carl Sagan was right: what a demon-haunted world so many still live in. It's just not there though, not any of it. What did Author C. Clark say, "a technology sufficiently advanced is indistinguishable from magic". I'd suppose evolution is a bit like that wouldn't you say? Supremely intricate, interconnected, and complex. Highly advanced indeed! Magic to some, less so to others.
 
Last edited:

1. What is heredity?

Heredity is the passing down of traits from parents to offspring through genetic information. This genetic information is encoded in DNA and determines an organism's physical characteristics.

2. How does heredity contribute to the diversity of life?

Heredity allows for the mixing and variation of genetic traits, leading to the diversity of life. This is because during sexual reproduction, genetic information from both parents is combined, resulting in unique combinations of traits in their offspring.

3. What is containment in relation to genetic modification?

Containment refers to the measures taken to prevent genetically modified organisms (GMOs) from escaping and potentially causing harm to the environment or other organisms. This can include physical barriers, such as greenhouse structures, or biological measures, such as engineering GMOs to be sterile.

4. How does metabolism play a role in an organism's survival?

Metabolism is the process by which an organism converts food into energy. This energy is then used for essential functions such as growth, maintenance, and reproduction. Without a functioning metabolism, an organism would not be able to survive.

5. Can heredity and metabolism be influenced by environmental factors?

Yes, both heredity and metabolism can be influenced by environmental factors. For example, exposure to certain pollutants or toxins can alter the genetic makeup of an organism, leading to changes in its physical traits. Additionally, environmental conditions can also affect an organism's metabolism and its ability to obtain and use energy from food sources.

Suggested for: Heredity, containment, metabolism.

Replies
5
Views
859
Replies
8
Views
2K
Replies
2
Views
1K
Replies
5K
Views
226K
Replies
3
Views
1K
Replies
6
Views
3K
Replies
1
Views
2K
Replies
4
Views
12K
Replies
2
Views
2K
Back
Top