Introduction to Unit 6 - Important Topics To Study
Unit 6 – A scoring unit in disguise! Having a weight age of almost 30 marks or more, most non-botany background students may feel this unit is not their cup of tea. But these are not so difficult concepts to grasp. In fact, the first 3 subunits actually have some repeated topics from Unit 1 like Electron Transport Chain, nitrogen metabolism etc. The topics listed below are definitely not to be missed.
6. SYSTEM PHYSIOLOGY - PLANT
A. Photosynthesis - Light harvesting complexes; mechanisms of electron transport; photoprotective mechanisms; CO2 fixation-C3, C4 and CAM pathways.
B. Respiration and photorespiration – Citric acid cycle; plant mitochondrial electron transport and ATP synthesis; alternate oxidase; photorespiratory pathway.
C. Nitrogen metabolism - Nitrate and ammonium assimilation; amino acid biosynthesis.
D. Plant hormones – Biosynthesis, storage, breakdown and transport; physiological effects and mechanisms of action.
E. Sensory photobiology - Structure, function and mechanisms of action of phytochromes, cryptochromes and phototropins; stomatal movement; photoperiodism and biological clocks.
F. Solute transport and photoassimilate translocation – uptake, transport and translocation of water, ions, solutes and macromolecules from soil, through cells, across membranes, through xylem and phloem; transpiration; mechanisms of loading and unloading of photoassimilates.
G. Secondary metabolites - Biosynthesis of terpenes, phenols and nitrogenous compounds and their roles.
H. Stress physiology – Responses of plants to biotic (pathogen and insects) and abiotic (water, temperature and salt) stresses.
Important Topics to be studied From CSIR NET Unit 6
- Phytohormones- All the plant hormones’ precursors, biosynthesis and function, special attention to signaling pathways should be given.
- Stomatal opening and closure by various triggers.
- Solute transport throughout the plant body is relatively an easy topic. Water potential concept.
- Photosynthesis – C2, C3, C4, CAM pathway, TCA, photorespiration, oxidative phosphorylation, cyclic and noncyclic photophosphorylation,
- Biotic and abiotic stress – Plant’s detailed mechanisms for adapting to different stress conditions.
- ABC model of the flowering plant, flowering genes in plants, repeated topic of Unit 5
- Nitrogen cycle and nodule formation: nod genes, bacteria in nitrogen fixation
- Secondary metabolites and their synthesis pathway, terpenes, isoprene derived molecules
- Sensory photobiology – phytochrome, cryptochrome, phototropin, photoperiodism, short day plants, long day plants, behavior and response of a plant to different colored lights.
REFERENCE BOOKS For CSIR NET UNIT 6
- Plant Physiology, by Lincoln Taiz and Eduardo Zeiger