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1.
The origin and evolution of biological organizations proceeding on Earth are put in a nonequilibrium thermodynamic framework within a cosmological context. The dynamic process responsible for chemical evolution leading to the origin of biological being depends upon consumer-dominating thermodynamics, in which the heat sink is taken to be active in extracting heat energy from a body at a higher temperature. Consumer-dominating thermodynamics follows from the fact that when a small hot body contacts a cold heat sink, it decreases the temperature at the possible fastest rate. The fastest temperature drop, when applied to chemical products being synthesized through the energy supplied from an external heat source, is selective in keeping only those products that can decrease the temperature at the fastest rate among the available alternatives. Synthesis of small organic molecules in the small ice grains in interstellar diffuse clouds irradiated by ultraviolet radiation is a representative case of consumer-dominating thermodynamics, in which diffuse clouds serve as cold heat sinks in the cosmological context. Another case of consumer-dominating thermodynamics predominant on Earth especially in the perspective of the origin and evolution of life is with submarine hydrothermal vents, in which the surrounding cold seawater constantly serves as the cold heat sink.  相似文献   

2.
A theory of the behavior of biological systems is proposed which is an extension of the conception of biological evolution (Gladyshev, 1977, Gladyshev, 1978) based on classical (equilibrium) thermodynamics. A thermodynamic theory of homeostasis is presented, in accordance with which homeostatic mechanisms of regulation are connected with a compensative shift of a fundamental quasi-equilibrium. The principle of least compulsion is formulated on the basis of thermodynamic laws and describes behavior of biological systems. A fundamental thermodynamic equation of behavioral processes is introduced. The Weber-Fechner law is shown to be a corollary of the fundamental thermodynamic equation.  相似文献   

3.

We give a review on the landscape theory of the equilibrium biological systems and landscape-flux theory of the nonequilibrium biological systems as the global driving force. The emergences of the behaviors, the associated thermodynamics in terms of the entropy and free energy and dynamics in terms of the rate and paths have been quantitatively demonstrated. The hierarchical organization structures have been discussed. The biological applications ranging from protein folding, biomolecular recognition, specificity, biomolecular evolution and design for equilibrium systems as well as cell cycle, differentiation and development, cancer, neural networks and brain function, and evolution for nonequilibrium systems, cross-scale studies of genome structural dynamics and experimental quantifications/verifications of the landscape and flux are illustrated. Together, this gives an overall global physical and quantitative picture in terms of the landscape and flux for the behaviors, dynamics and functions of biological systems.

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4.
As a closed thermodynamic system subject to an essentially constant free energy gradient, the biosphere must evolve toward a stationary state of maximum structuring and minimum dissipation with respect to this applied gradient. Since biological evolution occurs opportunistically through chance and selection, rather than as a direct response to the free energy gradient, the conformance of this phase of evolution with thermodynamics requires that natural selection, and the particular adaptive strategies employed by species of organisms, be related to the principles of increasing structuring and decreasing dissipation. In this paper, some general features of this relationship are proposed.  相似文献   

5.
6.
Biodiversity is hierarchically structured both phylogenetically and functionally. Phylogenetic hierarchy is understood as a product of branching organic evolution as described by Darwin. Ecosystem biologists understand some aspects of functional hierarchy, such as food web architecture, as a product of evolutionary ecology; but functional hierarchy extends to much lower scales of organization than those studied by ecologists. We argue that the more general use of the term “evolution” employed by physicists and applied to non-living systems connects directly to the narrow biological meaning. Physical evolution is best understood as a thermodynamic phenomenon, and this perspective comfortably includes all of biological evolution. We suggest four dynamical factors that build on each other in a hierarchical fashion and set the stage for the Darwinian evolution of biological systems: (1) the entropic erosion of structure; (2) the construction of dissipative systems; (3) the reproduction of growing systems and (4) the historical memory accrued to populations of reproductive agents by the acquisition of hereditary mechanisms. A particular level of evolution can underpin the emergence of higher levels, but evolutionary processes persist at each level in the hierarchy. We also argue that particular evolutionary processes can occur at any level of the hierarchy where they are not obstructed by material constraints. This theoretical framework provides an extensive basis for understanding natural selection as a multilevel process. The extensive literature on thermodynamics in turn provides an important advantage to this perspective on the evolution of higher levels of organization, such as the evolution of altruism that can accompany the emergence of social organization.  相似文献   

7.
The evolution of enzyme action in vivo is examined, in the light of established thermodynamic correlates of biological evolution. Adopting a “process” view of matter in the “living state,” the authors focus the analysis on the transition-state theory of reaction rates. Thus, the free-energy change associated with the transition-state barrier is seen as a primary target in the evolution of cellular metabolism. The utility and limitations of reductionistic approaches to enzyme evolution, based on the single enzyme, are explored first. Then, canvassing the wealth of evidence on the role of enzyme organization in vivo, the authors synthesize a “cytosociological” view of enzyme evolution. In this view, a composite (resultant) of individual transition-state barriers is deemed a more appropriate “potential function” for modification in the higher evolution of cell metabolism. The suggested direction of evolutionary changes in this function, dictated by the increasing “socialization” of enzyme action in vivo, stands as a novel postulate. This approach is shown to be completely consonant with current thinking on the thermodynamics of biological evolution, and to provide further insight into the nature of material transformations in the “living state”.  相似文献   

8.
Experimental reality in molecular and cell biology, as revealed by advanced research technologies and methods, is manifestly inconsistent with the design perspective on the cell, thus creating an apparent paradox: where do order and reproducibility in living systems come from if not from design?I suggest that the very idea of biological design (whether evolutionary or intelligent) is a misconception rooted in the time-honored and thus understandably precious error of interpreting living systems/organizations in terms of classical mechanics and equilibrium thermodynamics. This error, introduced by the founders and perpetuated due to institutionalization of science, is responsible for the majority of inconsistencies, contradictions, and absurdities plaguing modern sciences, including one of the most startling paradoxes - although almost everyone agrees that any living organization is an open nonequilibrium system of continuous energy/matter flow, almost everyone interprets and models living systems/organizations in terms of classical mechanics, equilibrium thermodynamics, and engineering, i.e., in terms and concepts that are fundamentally incompatible with the physics of life.The reinterpretation of biomolecules, cells, organisms, ecosystems, and societies in terms of open nonequilibrium organizations of energy/matter flow suggests that, in the domain of life, order and reproducibility do not come from design. Instead, they are natural and inevitable outcomes of self-organizing activities of evolutionary successful, and thus persistent, organizations co-evolving on multiple spatiotemporal scales as biomolecules, cells, organisms, ecosystems, and societies. The process of self-organization on all scales is driven by economic competition, obeys empirical laws of nonequilibrium thermodynamics, and is facilitated and, thus, accelerated by memories of living experience persisting in the form of evolutionary successful living organizations and their constituents.  相似文献   

9.
The mechanical behavior of most biological soft tissue is nonlinear viscoelastic rather than elastic. Many of the models previously proposed for soft tissue involve ad hoc systems of springs and dashpots or require measurement of time-dependent constitutive coefficient functions. The model proposed here is a system of evolution differential equations, which are determined by the long-term behavior of the material as represented by an energy function of the type used for elasticity. The necessary empirical data is time independent and therefore easier to obtain. These evolution equations, which represent non-equilibrium, transient responses such as creep, stress relaxation, or variable loading, are derived from a maximum energy dissipation principle, which supplements the second law of thermodynamics. The evolution model can represent both creep and stress relaxation, depending on the choice of control variables, because of the assumption that a unique long-term manifold exists for both processes. It succeeds, with one set of material constants, in reproducing the loading-unloading hysteresis for soft tissue. The models are thermodynamically consistent so that, given data, they may be extended to the temperature-dependent behavior of biological tissue, such as the change in temperature during uniaxial loading. The Holzapfel et al. three-dimensional two-layer elastic model for healthy artery tissue is shown to generate evolution equations by this construction for biaxial loading of a flat specimen. A simplified version of the Shah-Humphrey model for the elastodynamical behavior of a saccular aneurysm is extended to viscoelastic behavior.  相似文献   

10.
基因组序列k-mer的非随机使用规律及包含的生物学意义一直是人们关注的问题,目前还没有根本性进展。本文以七个物种的全部基因序列为样本,得到各物种基因组序列的8-mer频谱分布。发现狗和牛的频谱有三个峰,而斑马鱼、青鳉鱼、秀丽线虫和酿酒酵母的频谱只有一个峰,鸡的频谱分布形状介于两者之间。将8-mer集合按照XY二核苷含量分类,结果显示只有CG二核苷分类下0CG、1CG和2CG三类子集的频谱形成各自独立的单峰分布。对照随机序列,发现0CG模体是随机进化的,1CG和2CG模体是定向进化的,它们的使用频次远小于随机频次,且这种独立进化分离规律具有物种普适性。三个CG子集频谱之间的距离是产生单峰或多峰现象的根本原因。将七个物种基因组序列标准化到109bp,比较发现1CG和2CG子集频谱与物种进化显著相关,0CG子集频谱与物种进化无显著关系。可以认为三种CG模体各自执行着不同的生物学功能。基因组序列8-mer的独立分离规律为揭示基因组结构、基因组进化以及模体的生物功能提供了一种新的思维方式。  相似文献   

11.
As biomedical investigators strive to integrate data and analyses across spatiotemporal scales and biomedical domains, they have recognized the benefits of formalizing languages and terminologies via computational ontologies. Although ontologies for biological entities-molecules, cells, organs-are well-established, there are no principled ontologies of physical properties-energies, volumes, flow rates-of those entities. In this paper, we introduce the Ontology of Physics for Biology (OPB), a reference ontology of classical physics designed for annotating biophysical content of growing repositories of biomedical datasets and analytical models. The OPB's semantic framework, traceable to James Clerk Maxwell, encompasses modern theories of system dynamics and thermodynamics, and is implemented as a computational ontology that references available upper ontologies. In this paper we focus on the OPB classes that are designed for annotating physical properties encoded in biomedical datasets and computational models, and we discuss how the OPB framework will facilitate biomedical knowledge integration.  相似文献   

12.
The stability of ecosystems during periods of stasis in their macro-evolutionary trajectory is studied from a non-equilibrium thermodynamic perspective. Individuals of the species are considered as units of entropy production and entropy exchange in an open thermodynamic system. Within the framework of the classical theory of irreversible thermodynamics, and under the condition of constant external constraints, such a system will naturally evolve toward a globally stable thermodynamic stationary state. It is thus suggested that the ecological steady state, or stasis, is a particular case of the thermodynamic stationary state, and that the evolution of community stability through natural selection is a manifestation of non-equilibrium thermodynamic directives. Furthermore, it is argued that punctuation of stasis leading to ecosystem succession, may be a manifestation of non-equilibrium "phase transitions" brought on by a change of external constraints through a thermodynamic critical point.  相似文献   

13.
In this review, I will discuss the role of thermodynamics in both the determination and evaluation of the structure of biological macromolecules. The presentation relates to the historical context, state-of-the-art and projection into the future. Fundamental features relate to the effect of charge, exemplified in the study of synthetic and natural polyelectrolytes. Hydrogen bonding and water structure constitute basic aspects of the medium in which biological reactions occur. Viscosity is a classical tool to determine the shape and size of biological macromolecules. The thermodynamic analysis of multicomponent systems is essential fo the correct understanding of the behavior of biological macromolecules in solution and for the evaluation of results from powerful experimental techniques such as ultracentrifugation, light, X-ray and neutron scattering. The hydration, shape and flexibility of DNA have been studied, as well as structural transitions in nucleosomes and chromatin. A particularly rewarding field of activity is the study of unusual structural features of enzymes isolated from the extreme halophilic bacteria of the Dead Sea, which have adapted to saturated concentrations of salt. Future studies in various laboratories will concentrate on nucleic-acid--protein interactions and on the so-called 'crowding effect', distinguishing the behavior in bacteria, or other cells, from simple test-tube experiments.  相似文献   

14.
Microevolution in biological control: Mechanisms, patterns, and processes   总被引:4,自引:2,他引:2  
Microevolution may determine both the safety and efficacy of classical biological control. Despite a growing body of literature, there are several key unanswered questions regarding the role of evolution in biological control: (1) How common is local adaptation of natural enemies to their hosts or the environment in the native range? How critical is it for success of biological control to find locally adapted agents for importation? (2) Does adaptive evolution following introductions play an important role in biological control? (3) Do introductions of biological control agents impose bottlenecks in population size that reduce genetic variation, and is reduced genetic variation associated with low fitness and poor performance? (4) How great is the risk of evolution of host range of biological control agents? (5) What is the risk of target pests evolving resistance to biological control agents? If pests evolve increased resistance, will biological control agents evolve mechanisms to overcome that resistance? Here, we review the four fundamental processes of microevolution, and discuss how they interact in the context of biological control. We discuss our current state of knowledge regarding the outstanding questions, highlight the types of experiments that can address them, and suggest ways to use microevolution to define risks, and enhance efficacy and safety of biological control.  相似文献   

15.
The triumph of Darwinism, together with the rise of Genetics, produced the virtual abandonment of the problem of form in Biology. The statement that any adaptive theory is tautological is however poor, the adaptation concept having an evident intuitive content. As in Geometrical Optics, a ray of light is, among the crowd of continuous curves uniting two points, the one requiring the minimum time for the light to go from one point to the other, so actual evolution, among the crowd of virtual evolutions between two forms, is the one best fitted to face 'selective pressure' in a given environment. The effect of selective pressure on the genome is unfortunately a merely theoretical not quantifiable concept. Most biological forms are forced by their internal stability to an essential fixity, so that the leap from one type-form to another should be abrupt-catastrophic. A good theory of evolution depends on a proper understanding of specific form stability. Biology must eventually return to the concept of ideal structure, the Goethian 'Urbild'.  相似文献   

16.
This work develops a model for thermally induced damage from high current flow through biological tissue. Using the first law of thermodynamics, the balance of energy produced by the current and the energy absorbed by the tissue are investigated. The tissue damage is correlated with an evolution law that is activated upon exceeding a temperature threshold. As an example, the Fung material model is used. For certain parameter choices, the Fung material law has the ability to absorb relatively significant amounts of energy, due to its inherent exponential response character, thus, to some extent, mitigating possible tissue damage. Numerical examples are provided to illustrate the model’s behavior.  相似文献   

17.
Practitioners of classical biological control of invasive weeds are confronted with a dual expectation: to achieve successful control of plant invaders and to avoid damage to nontarget plants and adverse indirect effects. In this paper we discuss key issues that we consider to be crucial for a safe, efficient, and successful classical biological control project, and that have also caused some recent controversy. These include selection of effective control agents, host specificity of the biological control agents, implications of the genetic population structure of the target populations, and potential impact on native food webs. With regard to improving the success rate of biological control of plant invaders, we first emphasize the importance of a clear a priori definition of success and a more ecosystem-based approach to better document both negative effects of the invasive plant as well as potential positive and negative effects of introducing biological control agents. Secondly, pre-release impact assessment could be improved by better focusing on how to reach high densities of the control agents and by including tolerance to and compensation of herbivory. Thirdly, we advocate a reinforced effort to integrate and combine biological control in combination with existing or potential management options. Finally, we propose various ecological and evolutionary hypotheses in the framework of our topic to document that biological control programmes against plant invaders also offer a great opportunity to gain new insights into basic processes in ecology and evolution.  相似文献   

18.
Summary Recently published amino acid sequences are compared to those of other cytochromesc. Molecular phylogenies constructed by using an ancestral sequence method are compared to the classical biological view of invertebrate evolution. Problems associated with the analysis of sequences of different chain lengths and of high variability are discussed, and the logistics of increasing the representation of key invertebrate phyla is assessed.  相似文献   

19.
20.
Problems with entropy in biology.   总被引:1,自引:0,他引:1  
C J Smith 《Bio Systems》1975,7(2):259-265
Entropy has been widely referred to as a measure of biological order. The validity of this notion is discussed in conjunction with it's relation to the spontaneous creation of order. Information theory offers a quantitative method for characterization of order, however, it is not fundamentally connected to formalisms of irreversible thermodynamics, and it is severely limited because the meaning and value of the information is neglected. A completely general notation is proposed for including measures of order of a biological system in the entropy balance equation of irreversible thermodynamics. Problems of assigning energetic equivalents to measures of order are indicated, with a final focus on the problem of meaning and value.  相似文献   

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