Biological thermodynamics

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This article is about the biological study of energy transformation. For the body-oriented psychotherapy, see Bioenergetic analysis.

In thermodynamics, biological thermodynamics (Greek: bios = life and logikos = reason + Greek: thermos = heat and dynamics = power) or bioenergetics^[1] is the study of energy transformation in the biological sciences. More definitively, biological thermodynamics may be defined as the quantitative study of the energy transductions that occur in and between living organisms, structures, and cells and of the nature and function of the chemical processes underlying these transductions. Biological thermodynamics may address the question of whether the benefit associated with any particular phenotypic trait is worth the energy investment it requires.

1 History
2 Overview
3 References
4 External links

[edit] History

German-British medical doctor and biochemist Hans Krebs' 1957 book Energy Transformations in Living Matter (written with Hans Kornberg)^[2] was the first major publication on the thermodynamics of biochemical reactions. In addition, the appendix contained the first-ever published thermodynamic tables, written by K. Burton, to contain equilibrium constants and Gibbs free energy of formations for chemical species, able to calculate biochemical reactions that had not yet occurred.^[3]

[edit] Overview

Living cells and organisms must perform work to stay alive, to grow, and to reproduce themselves. The ability to harness energy from a variety of metabolic pathways so to channel it into biological work is a fundamental property of all living organisms. Thermodynamically, the amount of energy capable of doing work during a chemical reaction is measured quantitatively by the change in the Gibbs free energy.

Typical emphasis is on thermodynamic applications in biology and biochemistry. Principles covered include the first law of thermodynamics, the second law of thermodynamics, Gibbs free energy, statistical thermodynamics, binding equilibria, reaction kinetics, and on hypotheses of the origin of life. Presently, biological thermodynamics concerns itself with the study of internal biochemical dynamics as: ATP hydrolysis, protein stability, DNA binding, membrane diffusion, enzyme kinetics,^[4] and other such essential energy controlled pathways.

[edit] References

^ MeSH Bioenergetics
^ Alberty R (2004). "A short history of the thermodynamics of enzyme-catalyzed reactions". J Biol Chem 279 (27): 27831-6. PMID 15073189.
^ [ http://www.squaldrina.com/blog/medicine/krebss.htm Hans Krebs] - 1935
^ Reactions and Enzymes Chapter 10 of On-Line Biology Book at Estrella Mountain Community College.

Haynie, D. (2001). Biological Thermodynamics (textbook). Cambridge: Cambridge University Press.
Lehninger, A., Nelson, D., & Cox, M. (1993). Principles of Biochemistry, 2nd Ed (textbook). New York: Worth Publishers.