Stability, Thermodynamics, and Biological Organization

A universal informational code (genetic) and functional molecules (proteins and polypeptides). 

Employment of subunit construction, in which atoms form molecules, molecules form macromolecules, and so on, to form membranes, organelles, cells, tissues, and organs. 

A thermodynamic principle which prescribes the emergence of order in systems driven far from equilibrium and which also possesses appropriate kinetic parameters to ensure their removal from equilibrium. This thermodynamic contribution involves the interplay of information, energy, and matter with the living system, allowing for the coherent behavior synonymous with life. 

No single factor in the reductionist view of life is sufficient to explain the complexity of a biological system, yet each factor provides study areas which contribute significantly to the understanding of the whole. Enzymes may be considered the functional entities of life. They possess catalytic activity and conformational adaptability (implying plasticity or instability) and, when coupled with the protein synthetic apparatus that exists to replace denatured enzymes, they epitomize at the molecular level the semistable state known as life.  

Entropy is usually defined as the amount of disorder in a physical system, but, in a living system, entropy and its relationship to information and work requires redefinition. Brillouin (1962) has argued that entropy actually measures the lack of information about the true structure of the system. This lack of information introduces the possibility of a great variety of microscopically distinct structures which in practice we cannot distinguish from one another. This then raises the further question Is entropy a property of the system, of the observer, or of the relationship between them  

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