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:?
-minos-
Question: If we let alone a cell in an isolated box, the result will eventually be a chemical mixture and not the organized cell. The final disordered mixture is more entropic than the the organized cell. Doesn’t this prove that lowering entropy is a hallmark of life and every organism spends an amount of energy to increase its order??
Answer: Not necessarily. The story of any individual living being actually is a journey towards gradual decay into disordered chemistry. In the beginning it’s a zygote in which so much information is disclosed about future events, patterns, etc in a very small space. So we can say that a zygote has less entropy compared to later stages. This entropy gradually increases as we become infants, childs, teenagers, adults, etc, because less and less information is carried over time…
A simple cell in isolation will indeed decay quickly, but don’t forget that cells never exist in isolation, and higher organisms are much more complex and they interact with external energy. So the fact that they don’t instantly decay doesn’t necessarily mean that they use energy to decrease their entropy. Never underestimate our inability to fully comprehend the value of huge numbers.
I will explain:
Lets assume that a human body everyday degrades towards a higher entropic state. Lets assume for this reason, that after each day, the body loses, lets say 100 thousand of chemical reactions. Suppose we have an 80 years old man. He has lived 29200 days. This means that he has lost nearly 3 billion reactions during his lifetime. If the total amount of chemical reactions he has is, lets say 1 trillion, then after 80 years he will be composed of 997 billion reactions, which means virtually still 1 trillion. So the impact of the whole process on the chemical reaction count will be almost negligible.
Of course, if we stop giving him food, he will degrade faster, but this is an example how can life can be compatible with a gradual loss of entropy.
Question: Isn’t a cell is much more ordered than its components?
Answer: A cell is much more ordered than its components, but what you forget is that a cell never exists in isolation. It owes its existence and its properties to the fact that it belongs into a more generalized phenomenon that is called life, which is an open system and interacts with external energy.
Imagine you have a flask with water that is heated with fire. The molecules of water will start speeding randomly toward various directions. Virtually, what you are doing here with the cell argument is ignoring the fire and the majority of other water molecules and focusing only on subset of 2 specific molecules. These molecules will be perceived as gaining speed without an obvious reason, thus seeming to decrease entropy, as well as other known laws is such a way that it has to be characterized as an independent phenomenon that has to be studied….
Question: Isn’t glucose and oxygen more ordered than CO2 and water?
Answer: In order to build a house, you take the bricks and put them together. But you don’t build a cell in that way. A cell or a living being is the way it is because of the other living beings, ie because of the existence of what we call life on earth. Cells or living beings never exist in isolation.
Question: Isn’t it difficult to measure changes in order in particular organisms or cells?
Answer: Yes, but if life as a whole is a sum of entropy decreasing entities, then the entropy of the whole system will be decreasing accordingly over time. In this case, the total amount of entropic releases in the environment will be changing over time accordingly. I think this can be measurable....
-minos-
