Figure 14-12. A comparison of biological oxidations with combustion.

Figure 14-12A comparison of biological oxidations with combustion

(A) Most of the energy would be released as heat if hydrogen were simply burned. (B) In biological oxidation by contrast, most of the released energy is stored in a form useful to the cell by means of the electron-transport chain in the inner mitochondrial membrane (the respiratory chain). The rest of the oxidation energy is released as heat by the mitochondrion. In reality, the protons and electrons shown are removed from hydrogen atoms that are covalently linked to NADH or FADH2 molecules.

From: The Mitochondrion

Cover of Molecular Biology of the Cell
Molecular Biology of the Cell. 4th edition.
Alberts B, Johnson A, Lewis J, et al.
New York: Garland Science; 2002.
Copyright © 2002, Bruce Alberts, Alexander Johnson, Julian Lewis, Martin Raff, Keith Roberts, and Peter Walter; Copyright © 1983, 1989, 1994, Bruce Alberts, Dennis Bray, Julian Lewis, Martin Raff, Keith Roberts, and James D. Watson .

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