Plant Biochemistry and Physiology

Principles of bioenergetics and thermodynamics. Thermodynamic systems and their environments. I and II thermodynamics laws. Enthropy and free energy. Exo- and endo-ergonic reactions; energetically coupled reactions. ATP and phosphor group transfer. Other high energy compounds. Carbon redox states in compounds of biological interest. Oxy-reduction potential. Relationship between delta E and delta G. Oxy-reduction coenzymes. Redox reactions of biological interest. Thermodynamic and kinetic aspects of enzymatic catalysis. Michaelis-Menten¿s equation. Inhibition and regulation of enzyme-catalyzed reactions. Metabolic reations: the concepts of catabolism and anabolism. Carbon metabolism: degradation of storage polysaccharides (starch). Glycolysis and lactic and alcoholic fermentation. Energy yield of anaerobic glucose degradation. The Krebs cycle. Electron flux and oxidative phosphorylation. Mitchell¿s chemiosmosis theory. Energy yield of glucose aerobic degradation. Other mechanisms of O2 consumption in plants. Other pathways of glucose degradation: the pentose-P pathway. Basic aspects of the metabolism of storage lipids: energy yield of fatty acids degradation. Basic aspects of storage lipid degradation in plants: the glyoxilate cycle. Photosynthesis. The electromagnetic spectrum. Energy content of different wavelength radiations. Photosynthetically Active Radiation. Absorption and action spectra. Photosynthetic pigments: excitation and de-excitation phenomena. Photosystems, light-harvesting complexes, reaction centers. Energy transfer from the light-harvesting complexes to the reaction center. Accessory pigments. Photosynthetic electron flow and phosphorylation: the Z scheme. Non-cyclic and cyclic photophosphorylation. Herbicides disrupting the photosynthetic electron transport. Photooxidative damage. Carbon organication: C3 and C4 cycles, CAM metabolism. Photorespiration. Responses to light and temperature: light compensation point, CO2 compensation point. Plants and water. Definition of water potential and factors contributing to it in the plant cell: pressure, temperature, presence of solutes. Components of water potential in the plant cell: solute potential, matric potential, pressure potential. Osmotic phenomena: Van't Hoff's law. Isotonic, hypotonic, hypertonic solutions. Plasmolysis, cell turgor. Expansion growth. The soil-plant-atmosphere continuum. Water absorption by roots: the apoplastic and symplastic pathways. Transpiration. The driving force for the lift of the xylem sap in the xylem. Loss of water through the stomata, regulation of stomata opening. Photosynthate translocation in the phloem. Osmotically generated pressure flow. Role of active transport of H+ in sucrose loading and unloading. "Sinks" and ¿sources". Mineral nutrition. Plant nutrient requirements: micro- and macronutrients. Nutrient availability and plant growth. Solute transport in plant cells. Cell membranes and the plasmalemma: their role in cell physiology. Selective permeability. Chemical and electrochemical potentials and their role in determination of the direction of solute flux. Diffusion, active and passive transport. The Nernst¿ equation. Carriers and ion channels. Role of the PM H+-ATPase in generating the transmembrane electrochemical proton gradient and its role in secondary active transport. Absorption and assimilation of N, S and P. Micronutrient absorption: the case of Fe. Heavy metal toxicity: the case of Al. Mechanism of resistance to heavy metals: exclusion and detoxification. Plant growth regulators. General description of their peculiar characteristics. Evaluation of biological activity: biological tests. Auxins, gibberellins, cytokinins, abscisic acid and ethylene: description of a few specifici physiological effects and of a few related agricultural practices. Stress physiology. The concepts of stress. Abiotic stresses: low temperature stress, water stress, soil acidity stress, oxydative and radiation stresses. Biochemical and