The Degradation and Aging of Biological Systems as a Process of Information Loss and Entropy Increase

Abstract

The problem of the degradation and aging of bioorganisms is herein considered from the viewpoint of statistical physics. Two typical timescales in biological systems—the time of metabolic processes and the time of the life cycle—are used. A kinetic equation describing the small timescales of the systems’ characteristic processes in is proposed. Maintaining a biosystem in a time-stable state requires a constant inflow of negative entropy (negentropy). Ratios are proposed to evaluate the aging and degradation of systems in terms of entropy. As an example, the aging of the epithelium is studied. The connection of our approach to the information theory of aging is discussed, as well as theoretical constructions related to the concept of cooperon and its changing with time.

Disproving two widely accepted notions regarding entropy

“…In the 1880s, Hermann von Helmholtz used the word "disorder" to describe entropy, possibly from which the notion that entropy represents disorder (higher entropy means greater disorder) emerged [12]. This notion has been widely stated in various dictionaries [13], encyclopedias [5,6,14,15], textbooks [2,4], and many research articles [16][17][18][19][20][21][22][23], although this notion has faced a few challenges [3,[24][25][26][27]. This notion can be disproved for the following reasons (Figure 1).…”

“…According to the fundamental nature of entropy, entropy is analogous to energy with the unit of J/K [2-4]. By contrast, according to the explanations of disorder in various Oxford dictionaries [28], the Collins English Dictionary [29], and some entropy-associated research articles [16][17][18][19], disorder means untidiness, illness, and social abnormalities (e.g., violence or rioting). Disorder usually stems from the decline in the orderliness of a system, and its unit cannot be J/K.…”

“…This is the original, uncontroversial, and fundamental nature of entropy, which is pivotal to current thermodynamics Definition of disorder: untidiness, illness, and social abnormalities, as defined by various dictionaries and many entropy-associated papers. Its unit is not J/K Fact 9: The orderliness of life is encoded & provided by inherited genes, not by food Fact 8: The orderliness of life accumulates through long-term natural selection, not by entropy decline "disorder" in biology and social sciences [16][17][18][19][20][21][22][23], as exemplified by Schrödinger's negative entropy notion, which will be detailed below. Moreover, what we argue is just that entropy does not mean the "disorder" in biology, social sciences, or usual thinking.…”

“…The second law of thermodynamics, which states that heat can flow spontaneously from hot objects to cold objects and cannot flow reversely, has been frequently misused. For example, it was assumed by researchers from various fields that many natural or social systems tend to become more disordered over time due to the second law of thermodynamics [2, [4][5][6]18,19,32,[35][36][37][38][39][40][41][42]. The assumption that many natural or social systems tend to become more disordered over time is inherently correct due to some statistical probabilities because it is more probable for these systems to stay at a disordered status than at an ordered status.…”

Disproving Two Widely Accepted Notions Regarding Entropy

“…Disorder usually stems from the decline in the orderliness of a system, and its unit cannot be J/K. Although some people argue that the "disorder" in thermodynamics means different things from the "disorder" in biology, social sciences, or usual thinking [14], the notion that entropy represents disorder has been widely applied to investigate the "disorder" in biology and social sciences [16][17][18][19][20][21][22][23], as exemplified by Schrödinger's negative entropy Schrodinger′s widely accepted notion of negative entropy, which assumes that entropy represents disorder and is detrimental to animals, that animals continually increase their entropy, and that animal food harbors less entropy than animal excreta and so brings orderliness to animals, is incorrect…”