>>DNAunion: ... Experience shows us that the natural tendency IS away from
the complex and organized state associated with cells. First, let's start
from the building blocks and see if we get life. Take a single bacterium and
rupture its cell wall and plasma membrabe so that its contents leak out, but
remain confined to the area immediately surrounding the bacterium. Those
INTACT, PREEXISTING ENZYMES, DNA, RIBOSOMES, MITOCHONDRIA, ETC will *NOT*
reform a functioning cell. And the starting point just mentioned is far, far
above the level of organization that OOL researchers have achieved (no
prebiotically plausible mechanisms for the generation of enzymes, DNA,
ribosomes, mitochondria, etc.).
>>>THadley: Given an energy-efficient tendency in life to evolve multiple
dependencies among parts, as well as tendencies to lose structures or
mechanisms that are not essential to current functioning, I would think
that the individual parts of any given organism are far more likely to "die"
on their own than do anything else.
>
Take, for example, many kinds of symbiosis. Prior to the symbiotic
relationship, the two organisms are able to function independently. After
the relationship has been in existence for any significant length of time,
however, the symbiotes will die if seperated. Dependencies have evolved and
preexisting structures vital for independent existence have been lost or
diminished.>>>
DNAunion: I am not exactly sure if you are arguing against my statements,
supporting them, or neither. Let me point out though that I was discussing a
fully-autonomous bacterium, and not one involved in any form of symbiosis.
If one were to take a single fully-autonomous bacterium - keeping it supplied
with the nutrients, like sugars, it needed to survive all the time - and
lysed it, the "guts" (cytosol, ribosomes, circular DNA, etc.) would leak out:
the vital concentration gradient would be gone, the cellular reactions would
cease, and the cell (and all its components) would be dead (this is in fact
one method employed by bacteria to kill others: they produce an oligopeptide
that forms a leaky pore in the other bacterium). This process is
irreversible (following "times arrow"): the chemical reactions will not
self-organize back into a sustained metabolism capable of supporting life and
the bacterium will not re-assemble from its now disorder "parts". This is
true even if one heats the petri dish, or exposes it to intense UV, or jars
it around, or supplies any other kind of undirected energy.
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