Abiogenesis is a fascinating subject often glossed over my scientists.
Most just take it for granted that it happened without considering the amazing complexity involved.
We often hear expressions such as, " in the premordial soup, some amino acids joined to form proteins and then into self replicating single celled
organisms....ect" without really contemplating the magnitude of the steps needed.
If we allow for a pre-biotic soup with millions of amino acids, we still need to make the jump from amino acids to proteins. Forget for now that amino
acids are not stable in water.
"Amino acids.....to proteins"
Sounds simple enough at first glance, and for the lay person it may seem quite reasonable and logical.
However we should take an honest look at what is required to make this happen.
Half the amino acids are left handed and half are right handed. How likely is it, out of the millions of amino acids swimming in the soup, for the 20
correct left handed amino acids to somehow connect to form long chains necessary for life?
Not only do these long chains of the select 20 amino acids have to be linked together, they have to be linked in the correct order and in the exact
shape for each protein.
A typical simple protein was about 100 amino acids. During the life of even the simplest cell, it will use approx 200,000 proteins. Of these 200,000
proteins, some of them are specialized, for specific tasks. These are called enzymes and it is estimated that there are about 20,000 of these.
Without these enzymes the cell, even the simplest cell cannot survive.
What are the chances of these enzymes randomly forming in the pre-biotic soup? if you had the soup? One chance in 10 to the 40,000 power. This is 1
followed by 40,000 zeros.
How can we wrap our minds around a these kind of odds?
The chance is the same as rolling dice and getting 50,000 sixes in a row. And that is for only 2,000 of the 200,000 needed for a living cell. So to
get them all, roll 5,000,000 more sixes in a row!
But wait, we cant stop here. A simple cell with proteins and enzymes can not survive or reproduce without nucleotides. These are required to make the
DNA & RNA.. Oh, I almost forget, this annoying little detail, Proteins cannot be assembled without first having the nucleic acids.....but
wait...nucleic acids cannot be formed without the proteins....Well, lets just not dwell on that for now.
For any of this to work though the components of even the simplest cell need to protected from the soupy environment. It needs a membrane. Why?
Robert Shapiro, professor of chemistry at New York University and a specialist in DNA research, dispose of the chance formation of nucleotides and
nucleic acids in early earth’s environment:
"Whenever two amino acids unite, a water molecule is released. Two molecules of water must be set free in assembling a nucleotide from its
components, and additional water is released in combining nucleotides to form nucleic acids. Unfortunately, the formation of water in an environment
that is full of it is the chemical equivalent of bringing sand to the Sahara. It is unfavorable, and requires the expenditure of energy. Such
processes do not readily take place on their own. In fact, the reverse reactions are the ones that occur spontaneously. Water happily attacks large
biological molecules. It pries nucleotides apart from each other, breaks sugar-to-phosphate bonds, and severs bases from sugars."
So we need a membrane. But to create or form a membrane, a mechanism needs to already exist to do this. Call it a protein synthetic apparatus , if you
will. After all, something needs to assemble this membrane per the instructions contained in the DNA..
But wait, one more sticky little detail....a protein synthetic apparatus can only function if it is encased or held together by a membrane.
[edit on 3-3-2009 by Sparky63]