The thermodynamics of biological systems consists of two principal components: energetics and equilibrium; or in more scientific terms, enthalpy and free-energy changes of reactions in living matter. Biothermodynamics is a specialty within the discipline of chemical thermodynamics. Coverage in this chapter is restricted to mammals, with a special focus on the human body. Even with this limitation, biothermodynamics covers a vast array of chemical transformations. While the strictly thermodynamic aspects of this field are relatively simple, the molecular systems that are treated are extraordinarily complex. The species involved range from the proton to huge organic molecules (macromolecules) with molecular weights in the tens of thousands. The specialized nomenclature of biology is particularly difficult for non-biologists to cope with. Acronyms abound. To deal with these difficulties, this chapter defines all biological terms used in subsequent sections and where feasible, describes large molecules with structural diagrams. Rather than attempt to explain all mammalian systems for which a thermodynamic analysis is appropriate, the following sections select only a few applications and attempt to cover them thoroughly (from a thermodynamic viewpoint, not all of the biological implications).

Molecules of biological significance are mostly organic, consisting principally of carbon, hydrogen and nitrogen. Several inorganic species are important, as can be seen on the label of any multivitamin bottle. The organic species range in size from 3-carbon segments to the complex proteins, fats, and enzymes. However, the large molecules are combinations of simpler groups. Before turning to the thermodynamics of such systems, the molecular structure of several important biological species are displayed in the following section. The selection is by no means exhaustive, since the number and complexity of molecular species in mammals and plants is much too large to cover in a single chapter. Also, only a few species are singled out as examples of the application of thermodynamics, or more properly, thermochemistry, to living systems.

Solar Panel Basics

Solar Panel Basics

Global warming is a huge problem which will significantly affect every country in the world. Many people all over the world are trying to do whatever they can to help combat the effects of global warming. One of the ways that people can fight global warming is to reduce their dependence on non-renewable energy sources like oil and petroleum based products.

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