Life & Entropy: Is Life a Low-Entropy System?

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Is life an example of extremely low-entropy system? Why? Could someone tell me more about that?

(I know it depends on the way I define life, but I mean in general, we all know what does life mean)

Thanks
 
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Taturana said:
Is life an example of extremely low-entropy system? Why? Could someone tell me more about that?

(I know it depends on the way I define life, but I mean in general, we all know what does life mean)

Thanks

Well, I would say yes. Biosphere is unbelievably complex system of self-organized entities - low entropy, to say it in other words. This, of course, is not violation of the 2nd Law - Earth is being fed with solar energy which is re-emited as infrared radiation. This reemited radiation has much larger entropy than incoming solar radiation because approximately same amount of energy is re-radiated in different spectra - with much larger number of photons, let's say.
 
The average human body eats and metabolizes (oxidizes) plant food produced by photosynthesis (or eats animals who consume plants), and radiates heat at the rate of ~100 watts (= 2000 kiloCalories per day). This heat is the lowest form of waste energy, so entropy has to increase. So life increases entropy, one bite at a time.

Bob S