The Beginning of Life

[legion]

I was pondering today. Assuming evolution is correct, how did life begin? Initially, life would have had to appear "spontaneously". If life did appear spontaneously, one would assume this process would be repeatable, so why the need for reproduction? If the process is repeatable, why haven't we been able to witness or recreate it?

[on-ramp]

first you gotta prove that God exists.

[Jim Richards]

big bang, reproduction...hell, what else do you really need to know?

[nostatic]

its starts when tabs says so

[legion]

Originally posted by on-ramp
first you gotta prove that God exists.

Not trying to be a smartass here...and I'm not quite sure what you are getting at.

[on-ramp]

but seriously,

4.5 billion years go (yes, that's a damn long time), earth was formed.

then about 3.5 billion years ago, that's 1 billion years after the earth was formed, came the first life in the form of a prokaryotic cell. these cell bacteria dominated the earth.

then about 1.5 billion years ago, nucleated cells arose, these being of the eukaryotic type. (with nucleus and DNA).

then about .5 billion years ago, there was the cambrian explosion when multicellular eukaryotes arose

fast forward to today. we are the product of billion years of evolution. how fascination..

but why and how? i don't know.

[on-ramp]

Originally posted by legion
Not trying to be a smartass here...and I'm not quite sure what you are getting at.

if you prove that God exists, then you have the answers to all your questions.

[legion]

I guess what I'm getting at is that initial step has so far proven unrepeatable.

[artplumber]

Originally posted by legion
I was pondering today. Assuming evolution is correct, how did life begin? Initially, life would have had to appear "spontaneously". If life did appear spontaneously, one would assume this process would be repeatable, so why the need for reproduction? If the process is repeatable, why haven't we been able to witness or recreate it?

The (generally stated) theory is that there was a big soup of chemicals being radiated by both sun and cosmic and others (do we need to get into this?). This gave the chemicals enough energy to bond/attempt to bond multiple times in multiple ways. Enough of these new compounds are attempted that self-replicators appear - probably RNA first and amino acids appear. RNA begets DNA and complex proteins, as RNA's begin to encode amino acid sequencing. The proteins become associated with other chemicals, and capable of inducing chemical change (enzymatic activity). Along the way cell walls appear, and some of the proteins associate......

The key is a lot of time and interactions, because there are finite (though very small) chances that the radiation + chemicals = something useful or self replicating. The earth is no longer the "primordial soup" hence is no longer capable of producing these kinds of interactions. Several steps in this cascade have been demonstrated in labs, but not a complete generation of cell from soup + energy...

[on-ramp]

repeatable? i suppose if you kill off all life as we know it and the same conditions exist as they did 4.5 billion years ago, then yes, it might repeat. but there's no guarantee.

[Rob Channell]

So where was the energy BEFORE the big bang? Doesn't any system left to itself with no external energy input decrease to a lower entropy level? Doesn't it move towards chaos?

[W Scott Shores]

Here's a little secret from those of us with advanced degrees in biology: nobody really knows the answer. There are theories (see on-ramp's explanation), but this is one of the more faith-based areas of science.

[on-ramp]

Originally posted by Rob Channell
So where was the energy BEFORE the big bang? Doesn't any system left to itself with no external energy input decrease to a lower entropy level? Doesn't it move towards chaos?

about a millionth of a second before the explosion (big bang), the universe was the size of a small marble. then all hell broke loose.

that small marble within contained all the energy in the universe today.

again, this is a theory that someone came up with. it's amazing to think that a human being that has been around for less than 100 years can speculate on what occured 5 billion years ago.

[craigster59]

Originally posted by legion
I was pondering today. Assuming evolution is correct, how did life begin? Initially, life would have had to appear "spontaneously". If life did appear spontaneously, one would assume this process would be repeatable, so why the need for reproduction? If the process is repeatable, why haven't we been able to witness or recreate it?

So, was this after a hit of the "kush" or the "chronic"?

[Jared at Pelican Parts]

string theory

[K. Roman]

Who can figure this one out for us...EarlySMan???

[onZedge]

Edik's Lysurgically Induced Theorum:
This is just one of an infinite number of big bangs. They have always been and they will always be. It is the "heartbeat" of conscious existence.

[Evans, Marv]

One of the latest ideas is that incoming meteoritic material contained organic building blocks which may have enabled the life process to get started. An interesting little tidbit to me was that after the earth had cooled, it rained for more than 60K years.

[M.D. Holloway]

R. Bruce Merrifield, a Noble Prize winning scientist developed an ingenious method for assembling proteins. He perfected a technique called solid phase peptide synthesis. The old methods were thought that proteins were assembled in situ but it proved almost impossible. He did it differently - using a solid phase not liquid media.

I raise this point because I am a firm believer that protein synthesis (and eventual liquid crystal synthesis which then leads to self assembling / replicating molecules) occurs on the surface of solids (clays) rather than an ocean, solution or soup.

As a side note, we know very little about the small life forms found in soil. In fact, the rain forests are void or bacteria in the dirt compared to the tundra which is rich in microbes. We know nothing about the lil critters deep down. Deep dpwn is where life began. Maybe if we look there and try to understand proto-life forms like virus and super-virus will we begin to understand the origins of life.

[carambola]

if you want to repeat the begining, send an electrical charge through water in a vacuum. google this info, it's been done