Assessment of the contributions of metabolic pathways to plant respiration. Respiration of protein. Respiration of lipid. Respirantion of carbohydrate. Enzyme flexibility as a molecular basis for metabolic control. Feedback regulation of metabolic pathways. Phenomenology of the regulatory behavior of enzymes. Molecular devices that command the regulatory behavior. Models and theoretical predictions of enzyme flexibility. The evolution of catalytic function and cooperativity. Direct oxidases and related enzymes. The activities of direct oxidases and related enzymes in plants. Ascorbate oxidase. Polyphenol oxidase. Laccase. Utilization of peroxide and oxygen radicals in plants. Electron transport and energy coupling in plant mitochondria. Mitochondrial preparations. Components of the respiratory chain. Carrier sequence in the plant respiratory chain. Energy coupling in plant mitochondria. Nature and control of respiratory pathways in plants: the interaction of cyanide-resistant respiration with the cyanide-sensitive pathway. Mitochondrial and biochemical aspects. Tissue, organ, and physiological aspects. Control of the krebs cycle. Regulation by ADP turnover. Regulation by enzyme turnover. Regulation by metabolite transport. Regulation by other methods. Some special cases. Enzyme nomenclature. The regulation of glycolysis and the pentose phosphate pathway. Regulation of glycolysis. Regulation of gluconeogenesis. Regulation of the pentose phosphate pathway. Hydroxylases, monooxygenases, and cytochrome P-450. General aspects of metabolic hydroxylations. Cytochrome P-450-dependent mixed-function oxygenases. Hydroxylase functions of phenolases. Prolyl hydroxylase. Peroxygenase. Hydroxylations catalyzed by peroxidases. Fatty acid hydroxylations. Hydroxylation reactions in metabolic pathways. One-carbon metabolism. The occurrence of folate derivatives in plants. The generation of C1 units. Interconversion of C1 units within the folate pool. Utilization of C1 units. The regulation of C1 metabolism. Respiration and senescense of plant organs. Patterns of respiratory behavior during senescence of plant organs. The significance of changes in respiratory activity in relation to ripening and senescence in fruit. Respiration and related metabolic activity in wounded and infected tissues. Increased respiration in response to wounding or infection. Biochemical events related to increased respiration. Relationship between increased respiration and metabolism activated by wounding or infection. Physiological roles for enhanced respiration and its related metabolism. Use of wounded and infected tissues for analyzing metabolic principles. Photorespiration. Metabolic pathways for glycolate biosynthesis and metabolism. The glycerate pathway. CO2 and O2 and energy loss during photorespiration. Relationship of photorespiration to sucrose and starch synthesis. Photorespiration in algae. Photorespiration in C4 plants. O2 uptake during electron transport in chloroplasts. Regulation of cellular synthesis by photorespiration. Regulation of photorespiration. Speculation on the function of photorespiration. Effects of light on "Dark" respiration. Physiological aspects. Biochemical aspects of respiration in the light. Anaerobic metabolism and the production of organic acids. The diffusion of oxygen. Growth in the absence of oxygen. End products of anaerobic metabolism. Control of pH. Theories of flood tolerance. Effect of low temperature on respiration. The effect of temperature on the rate of enzyme reactions. Temperature-induced changes in the Ea of enzyme reactions. The effect of increasing the Ea of respiratory activity on metabolic balance. Metabolic imbalances in the tissues of chilling-sensitive plants at low temperature. The use of tissue cultures in studies of metabolism. Available types of systems. Studies with established cultures. Studies of metabolism in cell cultures.