Plant Biochemistry and Metabolism (U01276)

? Credit Points : 10 ? SCQF Level : 10 ? Acronym : BIO-4-PLbioc

We aim to introduce you to aspects of the synthesis and function of physiologically interesting components of plant cells. There is emphasis on questions which are not yet completely answered and are therefore the subject of active current research; there is also emphasis on aspects of biochemistry and physiology that are seen in plants but not animals or prokaryotes. The course is firmly based on a 'how to do it' approach, and you will learn basic methods for analysing important plant components (including sugars, polysaccharides, lipids, amino acids, secondary metabolites, lignin and inorganic nutrients). We deal with the mechanism of plant growth, including the synthesis, assembly and turnover of the polysaccharides and glycoproteins of primary cell walls. We consider how the different cell-wall polymers become cross-linked to each other and thus assembled into a coherent 'fabric' which is both physically strong and yet able to stretch in order to accommodate cell growth. We discuss evidence that plant cell walls are metabolically active, undergoing turnover to enable growth and fruit ripening, and also producing biologically active oligosaccharides that possess hormone-like activities. Additional topics include the biochemistry of boron (why is it an essential element for plants but not for most other organisms?), vitamin C (essential in the human diet, but how and why do plant produce it?), and the physiology of seed germination and its control. We discuss how photosynthesising leaves control the distribution of fixed carbon between competing interests (housekeeping functions within the leaf, sucrose production for export via the phloem to supply the non-photosynthetic roots and seeds, and the manufacture of starch grains for storage purposes).