FOURTH SEMESTER BOTANY
Plant Physiology and Metabolism
Unit – 1: Plant-Water relations
1. Importance of water to plant life, physical properties of water, diffusion, imbibition, osmosis. water potential, osmotic potential, pressure potential.
2. Absorption and lateral transport of water; Ascent of sap
3. Transpiration: stomata structure and mechanism of stomatal movements (K+ ion flux).
4. Mechanism of phloem transport; source-sink relationships.
Unit – 2: Mineral nutrition, Enzymes and Respiration
1. Essential macro and micro mineral nutrients and their role in plants; symptoms of mineral deficiency
2. Absorption of mineral ions; passive and active processes.
3. Characteristics, nomenclature and classification of Enzymes. Mechanism of enzyme action, enzyme kinetics and Enzyme inhibition
4. Respiration: Aerobic and Anaerobic; Glycolysis, Krebs cycle; electron transport system, mechanism of oxidative phosphorylation, Pentose Phosphate Pathway (HMP shunt).
Unit – 3: Photosynthesis and Photo respiration
1. Photosynthesis: Photosynthetic pigments, absorption and action spectra; Red drop and Emerson enhancement effect
2. Concept of two photo systems; mechanism of photosynthetic electron transport and evolution of oxygen; photo phosphorylation
3. Carbon assimilation pathways (C3,C4 and CAM);
4. Photo respiration - C2 pathway
Unit – 4: Nitrogen and lipid metabolism
1. Nitrogen metabolism: Biological nitrogen fixation – asymbiotic and symbiotic nitrogen fixing organisms. Nitrogenase enzyme system.
2. Lipid metabolism: Classification of Plant lipids, saturated and unsaturated fatty acids.
3. Anabolism of triglycerides, β-oxidation of fatty acids, Glyoxylate cycle.
Unit – 5: Plant growth - development and stress physiology
1. Growth and Development: Definition, phases and kinetics of growth.
2. Physiological effects of Plant Growth Regulators (PGRs) - auxins, gibberellins, cytokinins, ABA, ethylene and brassinosteroids.
3. Physiology of flowering:Photoperiodism, role of phytochrome in flowering.
4. Seed germination and senescence; physiological changes.
5. Outlines of Stress Physiology (Temperature & Satiety)