Energy metabolism basic concepts

PART II TRANSDUCING AND STORING ENERGY Chapter 14 Metabolism Basic Concepts and Design 229... 

Explain the basic concepts of metabolism, and understand the energy relationships of biochemical reactions. 

The essence of these interactions, like that of all interactions in biochemistry, is energy. To understand much of biochemistry—bond formation, molecular structure, enzyme catalysis—we need to understand energy. Thermodynamics provides a valuable tool for approaching this topic. We will revisit this topic in more detail when we consider enzymes (Chapter 8) and the basic concepts of metabolism (Chapter 14). 

A review of the basic concepts of metabolism in Chapter 14 and mitochondrial structure, redox potentials, the proton-motive force, and free-energy changes in Chapter 18 will help you to understand this chapter. 

The increase by 1/3 found in the value of unassimilated food energy in predatory fish is so substantial that it was proposed to introduce a special term (U) into the balance equation, to denote liquid excretion. In the literature, a concept of metabolized energy was adopted, implying assimilated energy (A) minus the liquid excretion energy (U) (Brody, 1945 Brett and Groves, 1979 Jobling, 1983). The basic equation would then be ... 

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