>>David Bowman: Since responding to DNAunion's long 2-part post of 22 OCT
would require more time than I have, and since any response I would make to
it would most likely be met with a further interminable barrage of low
signal-to-noise ratio responses that would be demanding of further cycles of
correspondence on my part, I have decided to spare the reflector readership
from suffering through it all by not responding to those posts in the first
place.
DNAunion: Anyone care to step in for David?
First, a few definitions need to be addressed.
ORGANIZE
"Organize: … To arrange elements into a whole of interdependent parts. …"
Webster's Ninth New Collegiate Dictionary.
Further information on Organize can be found in Webster's by looking up
Order. "… ORDER, ARRANGE, MARSHAL, ORGANIZE, SYSTEMATIZE, METHODIZE mean to
put persons or things into their proper places in relation to each other. …
ORGANIZE implies arranging so that the whole aggregate works as a unit with
each element having a proper function…"
Thus we can see that something that is organized is in a "higher state" than
something that is ordered. As I said elsewhere, leaves in a pile are
ordered, but not organized. The parts of a cell (or a car engine) are both
ordered and organized.
OVERCOME
Looking at the definition of Order: "… CONQUER, VANQUISH, DEFEAT, SUBDUE,
REDUCE, OVERCOME, OVERTHROW mean to get the better of by force or strategy.
… OVERCOME suggests getting the better of with difficulty or after hard
struggle…" Webster's Ninth New Collegiate Dictionary.
I believe that my *figurative* use of the word overcome has been appropriate.
Life is in a constant *struggle* to maintain itself (it's cells) far from
equilibrium, and in a constant *struggle* to oppose the natural tendency
toward greater disorder. Furthermore, I have consistently enclosed the word
overcome in double quotes, such as "overcome", to indicate that it should not
be taken literally. In addition, I explained my particular usage by giving
examples.
Nowhere did I state that entropy was somehow eliminated, or done away with,
or became non-existent, or killed: it was always present, just that a flow of
energy or matter through the system could "outweigh" its negative effects.
Interestingly, my other molecular cell biology college text actually uses the
term overcome (with no double quotes) in a similar manner, stating that a
great enough positive change in entropy can cause a reaction to be
thermodynamically spontaneous despite its having a large positive change in
enthalpy (I don't have that text on me now, but if someone would like the
exact wording, I could look it up and post it).
Now, on to my supporting material from one of my college cell biology texts.
"As this chapter has emphasized, the driving force in all reactions is their
tendency to move toward equilibrium." (Wayne M. Becker, Jane B. Reece, &
Martin F. Poenie, The World of the Cell: Third Edition, Benjamin/Cummings
Publishing Co., 1996, p133)
DNAunion: Very important point - keep it firmly in mind. All reactions have
a tendency to move toward equilibrium.
"But to understand how cells really function, we must appreciate the
importance of reactions that move toward equilibrium without ever achieving
it." (Wayne M. Becker, Jane B. Reece, & Martin F. Poenie, The World of the
Cell: Third Edition, Benjamin/Cummings Publishing Co., 1996, p133)
DNAunion: If the natural tendency for chemical reactions is to reach
equilibrium, yet the reactions in a cell do not, then there must be
*something* that opposes that natural tendency.
"At equilibrium, the forward and backward rates become the same for a
reaction, there is no net flow of matter in either direction, and, most
importantly, no further energy can be extracted from the reaction because
[the change in Gibbs free energy] is zero for a reaction at equilibrium. For
all practical purposes, then, a reaction at equilibrium is a reaction that
has stopped. But a living cell is characterized by reactions that are
continuous, not stopped. A cell at equilibrium would be a dead cell." (Wayne
M. Becker, Jane B. Reece, & Martin F. Poenie, The World of the Cell: Third
Edition, Benjamin/Cummings Publishing Co., 1996, p133)
DNAunion: Sounds familiar, no? Of course it does, that's what I've been
saying repeatedly in the last couple of my posts on this subject.
"We might, in fact, define life as a continual struggle to maintain a myriad
of cellular reactions in positions far from equilibrium because at
equilibrium no net reactions are possible, no energy can be released, no work
can be done, and the thermodynamically improbable order of the living state
cannot be maintained." (Wayne M. Becker, Jane B. Reece, & Martin F. Poenie,
The World of the Cell: Third Edition, Benjamin/Cummings Publishing Co., 1996,
p133)
DNAunion: A continual *struggle*? *Against* the natural tendency of
reaching thermodynamic equilibrium? The *order* associated with life is,
thermodynamically-speaking, highly improbable? Sounds to me like there *is*
something that opposes matter's being organized in the complex ways
associated with life.
"Thus, life is possible only because living cells maintain themselves in a
steady state far from thermodynamic equilibrium." (Wayne M. Becker, Jane B.
Reece, & Martin F. Poenie, The World of the Cell: Third Edition,
Benjamin/Cummings Publishing Co., 1996, p133)
DNAunion: De ja vu - I said that too.
"This [steady] state [far from equilibrium], in turn, is possible only
because a cell is an open system and receives large amounts of energy from
its environment. If the cell were a closed system, all its reactions would
gradually run to equilibrium and the cell would come inexorably to a state of
minimum free energy, after which no further changes could occur, no work
could be accomplished, and life would cease. The steady state so vital to
life is possible only because the cell is able to take up energy continuously
from its environment, whether in the form of light or preformed organic food
molecules. This continuous uptake of energy and the accompanying flow of
matter make possible the maintenance of a steady state in which all the
reactants and products of cellular chemistry are kept far enough from
equilibrium to ensure that the thermodynamic drive toward equilibrium can be
harnessed by the cell to perform useful work, thereby maintaining and
extending its activities and structural complexity." (Wayne M. Becker, Jane
B. Reece, & Martin F. Poenie, The World of the Cell: Third Edition,
Benjamin/Cummings Publishing Co., 1996, p133)
DNAunion: My statements have agreed with this nicely. A continuous flow of
matter and energy are *required* to keep the cell far from thermodynamic
equilibrium. If that flow ceases, the structural complexity and order of the
cell or cells cannot be maintained against the natural tendency towards
greater disorder. This clearly indicates that matter *does* have something
against being organized in complex ways like those associated with life.
I will take a short detour to give another example: rigor mortis. Upon
death, the sarcoplasmic reticulum in skeletal muscle fibers becomes unable to
maintain the proper calcium ion concentrations inside and Ca++ cations begin
leaking out into the sarcoplasm (the inside of the individual muscle cells).
Note that this results in an increase in the randomness of the calcium
cations, just as a drop of food coloring diffusing throughout a glass of
water does. Without getting too technical, calcium ions cause portions of
muscle fibers to undergo "cock, grab, pull, release; cock, grab, pull,
release" cycles, sliding thick and thin filaments across each other, inward
toward a common center, shortening the muscle fiber: i.e., the muscle fiber
contracts. But the body has no means of elongating a muscle fiber, just
contracting one. (Under normal conditions, the already-contracted muscle
ceases to actively contract and either an antagonistic skeletal muscle
contracts, or gravity or some other external force steps in, in order to
elongate the originally-contracted muscle fiber). So as long as calcium ions
continue to be released from the sarcoplasmic reticulum into the sarcoplasm
and/or are not removed by being taken back up into the sarcoplasmic reticulum
(as is normal), the muscle fiber will continue to contract (or remain fully
contracted, if already contracted). Since this breakdown in control occurs
in all muscle cells "at the same time", all the human's skeletal muscles
tense up tightly and remain fully contracted, causing the stiffness
associated with rigor mortis. But as time goes by, tissues begin to break
down further (it's that continual need to "battle" the tendency toward
increases in disorder again), including the skeletal muscles. As the muscle
fibers break down, obviously, they can no longer actively contract or remain
tensed: rigor mortis eventually ceases without outside intervention.
Again, the organized and complex arrangement of matter that comprises
skeletal muscle fibers is "unnatural" - the human body must continually
struggle actively to maintain that order and organization, and once it can do
so no more, disorder becomes greater and greater over time.
"Have you ever considered how downright improbable you are? … What you are
contemplating is the thermodynamic improbability that the order of the human
body (or any other biological entity) could come into being spontaneously or,
for that matter, could be maintained in such a highly ordered state once it
had come into being. On the contrary, things in nature usually proceed from
an ordered state to a less ordered one, not the other way around." (Wayne M.
Becker, Jane B. Reece, & Martin F. Poenie, The World of the Cell: Third
Edition, Benjamin/Cummings Publishing Co., 1996, p112)
DNAunion: Yes, because matter does have something against its being
organized in complex ways. But the tendency towards greater disorder can be
"overcome".
"However improbable a structure may be because of its order, it can always be
generated if sufficient energy and information are available. Energy and
information are, in other words, two indispensable prerequisites for the
existence of life. Order can be brought about, maintained, and even extended
in biological systems provided that adequate information and energy are
available. The information is required to specify what form that order
should take, and the energy is needed to drive the reactions and processes
that lead to the order." (Wayne M. Becker, Jane B. Reece, & Martin F. Poenie,
The World of the Cell: Third Edition, Benjamin/Cummings Publishing Co., 1996,
p112)
DNAunion: Again, my statements have agreed with this nicely.
Finally, it might be that David Bowman and I are looking at different things
- this has occurred in other of my discussions. Let me bring in another
example that should help explain what I am talking about.
When phospholipids (of the correct length and in the proper number) are
introduced into water, they spontaneously form a phoshoplipid bilayer that
then curls up into a ball (a liposome). One person was arguing that this
represented a localized increase in order, while his/her opponent was arguing
that it was an example of a decrease in order. Who was correct? The one
person took only the phosopholipids into consideration, and they do become
more ordered as the individual dispersed (i.e., randomly distributed)
phospholipids aggregate to form a single larger grouping (i.e., less random
distribution): AND their freedom of movement does become more restricted. So
the person arguing that it was an increase in order was correct, right?
Well, the opponent was taking more into consideration: the water as well.
When the phospholipids are introduced into water, their long hydrocarbon
tails will not dissolve in it (water molecules are polar) because they are
hydrophobic ("water fearing"). In order for them to become inserted amongst
the water molecules, they would have to disrupt existing hydrogen bonds
without being able to form any bonds with water in return, which is a "no
no". Thus, water molecules surround the individual phospholipid tails
forming "water cages" around them. The water molecules in these cages are
restricted in their movement: that is, they are ordered. But when two
phospholipids come together, the two small water cages can be replaced by a
single larger water cage surrounding the now single group of hydrophobic
tails - *and the single large water cage will consist of fewer water
molecules than did the two smaller ones combined*. Thus, a net increase in
the freedom of movement in the water molecules: disorder increases. This
same process continues because in each instance, it reduces the number of
water molecules restricted to surrounding phospholipid tails. So the
phospholipids become more ordered, but the water becomes less ordered: the
net effect is a decrease in order, just as entropy insists. So if one views
only the molecules of primary interest, the result is an increase in order,
but if one views instead the molecules of primary interest and those they
interact with, the result is a decrease in order. Note that for any decrease
in entropy, there MUST be an equal or greater compensatory increase in
entropy elsewhere: this applied in the above example. No one was trying to
get around that fact.
Now, I am not sure if this is the case: I don't know if David and I are
looking at the same thing from different perspectives. To be honest, I can't
determine the exact details of his position because most what he is saying is
way over my head.
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