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Author Topic: Does the entropy of life actually increase as any common chemistry?  (Read 1704 times)

Offline minass

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According to the common viewpoint, life is an open system that interacts with external energy. The mainstream viewpoint is that this causes a decrease in its entropy, enabling life to emerge on the first place and to sustain itself, thus avoiding chemical chaos. In return, the system releases entropy to its surroundings so that the 2nd law of thermodynamics is not violated.
 
The common view that the origin of life is characterized by accumulation of order, as order means lower entropy.
 
However, the term order can be very subjective, as an object non involved in life such as a rolling stone can say that it sees no order or no meaning in living systems’ chemical reactions. Just chaotic chemistry. So lets just leave order on the side and calculate entropy changes directly.
 
Does the entropy in living systems actually increase or decrease? If it increases, is it doing so in a pattern that suggests an arbitrary system? Although I am not a physicist I will welcome suggestions on how to calculate changes in the entropy of life over time.
 
Here are some simple approaches: Forgive me for any mistakes…

1)Does the life-associated heat production increase or decrease over time and how? Can life-associated changes in temperature be calculated?
2)Since chemical systems with higher entropy are characterized by increased gas production, does a life-associated gas production increase over time? In a system of decreasing entropy, one would expect a declining life-associated gas production…
Any ideas:?


 

Offline alysdexia

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According to the common viewpoint, life is an open system that interacts with external energy. The mainstream viewpoint is that this causes a decrease in its entropy, enabling life to emerge on the first place and to sustain itself, thus avoiding chemical chaos. In return, the system releases entropy to its surroundings so that the 2nd law of thermodynamics is not violated.
 
The common view that the origin of life is characterized by accumulation of order, as order means lower entropy.
 
However, the term order can be very subjective, as an object non involved in life such as a rolling stone can say that it sees no order or no meaning in living systems’ chemical reactions. Just chaotic chemistry. So lets just leave order on the side and calculate entropy changes directly.
 
Does the entropy in living systems actually increase or decrease? If it increases, is it doing so in a pattern that suggests an arbitrary system? Although I am not a physicist I will welcome suggestions on how to calculate changes in the entropy of life over time.

The lay has misappropriated well-defined scientific terms like order and entropy when they mean the opposite of what it thinks they mean.  Without arithmètic and semantics, nothing can be proven.

entropy ~ disorder ~ complexity ~ information ~ propagation ~ evolution.  Life and evolution are the result of and proportional to entropy.  The alternative of entropy is if all matter were cleanly arranged in frozen blocks, like atom with like atom, with no reactions.

One measure of a material's entropy is its heat capacity, or specific (gravimetric) heat capacity-mass.  This goes proportional with mode and potential.  Specific heat capacity goes proportional with hydrogen bonding.

Reaction rate is governed by Gibbs free energy, the sum of reaction enthalpy or heat and the negative product of entropy and temperature shift (or rather entropy shift and temperature; I wonder why not both?), and goes proportional to its negativitude.
 
Quote
Here are some simple approaches: Forgive me for any mistakes…

1)Does the life-associated heat production increase or decrease over time and how? Can life-associated changes in temperature be calculated?
2)Since chemical systems with higher entropy are characterized by increased gas production, does a life-associated gas production increase over time? In a system of decreasing entropy, one would expect a declining life-associated gas production…
Any ideas:?

1: Life can only convert a sliver of environmental heat and the fossil record and history repeatedly show explosions then mass extinctions of species where in the late periods monocultures take over the environment and kill off other kinds of life.  Bactèria lead the breeding and killing; the most power, metabolic and otherwise, and mass is wielded by fòtosýnthetic aýtotrofs.  The earth had a warm Atlantic period and even warmer Mesozoic, more free oxygen and carbon dioxide (I think), gigantism, so the Milancovich and Wilson cýcles determine the heat that life can absorb.  Whenever a supercontinent forms it cuts off convection currents and makes a huge desert in the interior.
2: As long as producers lead, carbon dioxide dissolves, reduces, and polýmerizes so local entropy decreases.  However life [and dead life] decreases the earth's albedo, keeps it warm and acid, and drives lesser-entropy minerals like carbonates and hydrates into solution and dissociation into gases.  Overall entropy of the earth and sun should increase.
 

Offline puppypower

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There are two entropy factors, going on at the same time, within life. The sum of these two factors will result in a net increase in entropy. On the one hand, the many structures of the cell define lowered entropy. For example, proteins fold with perfect folding, with probability equal to 1.0. Protein folding takes away all randomness from protein structures, wth the random assumption not valid for protein. I am not sure why random is still used, other than as a retro empirical tool.

The reason for perfect protein packing/folding is connected to the interaction of the proteins with water. Folding of protein is done via hydrophobic interactions, meaning the protein folds to get away from and minimize the interface with water The potential with the water forces the protein into a perfect fold. It sort of like mixing water and oil, with the oil wanting to get out of the water, to form its own layer. Protein were originally assumed to pack with random variations due to thermal fluctuations in the water. But as the investigative technology evolved, it was found protein packed perfectly. This eliminated the random assumption, but that assumption never went away.

Once all the protein have lowered entropy, via perfect packing, this creates a stubborn structural entropy potential, which requires that entropy has to increase, elsewhere, so the entropy of the cell can increase on accordance with the second law of thermodynamics. This is done, in large part, via the metabolism. In metabolism, food is ground down and digested to make smaller molecules like CO2, which have more degrees of freedom; define higher entropy.

If we add the lowered protein entropy due to perfect protein packing, and the increase metabolic entropy, the sum is consistent with the second law, which states that the entropy of the universe has to increase. The more ordered and large the early cells became, the higher its metabolic and other entropy increasing needs became.

Entropy in chemistry is a state function, which means there is a specific amount of entropy for any given state of matter. Entropy is often describe as randomness and change. This is true, but for any given state of matter, this randomness and change adds up to a very specific amount. For example the entropy of water at 25C is always 6.6177 J ˣ mol-1 ˣ K-1. This is the same in all labs and does not change with time. The second law needs the state to change for an increase to occur. We can add dissolved things to water for a new state.

With life, since the entropy is very low and stabilized within its many protein structures, each protein is like a state that defines a specific low entropy value. The second law will attempt to increase this at or near the protein. It may bring in other materials into that zone. The entire cell represents a zone of reduced entropy structuring, which sets a potential with the higher entropy state of the environment. This helps things flow to the cell, since this flow allows the entropy to increase.

In cell cycles, since the cell is making plenty of new protein for its two future daughters cells, the result is a sharp decline in structural entropy as protein concentrations build. The result is a need for higher entropy. Metabolism gets really high. These will parallel. Two daughter cells have more disorder or entropy than one mother cell; double the freedom, therefore the formation of the two daughter cells satisfies the needs of the potential created by the enhanced lowered protein entropy.

Early cells did not have all the bells and whistles of modern cells. However, they still had structural entropy potential to help drive cell cycles. It was never about random. Random is a retro man made tool to help explain the unknown using black boxes. I am not sure why this is still used, when perfect protein packing disproved this. at the nano-scale. Part of this need to stay retro, and not move forward to the future, has to with under estimating the importance of water; water is what packs protein perfectly and keeps it there.
 

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