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BIL 226, General Botany – Krempels Study Guide for Exam II the Root

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BIL 226, General Botany – Krempels Study Guide for Exam II the Root BIL 226, General Botany – Krempels Study Guide for Exam II The Root Know the various functions of the root. Know the meaning/significance of: primary root, taproot, lateral roots, fibrous roots. Know the general characteristics of roots and how root morphology and function can vary with environmental conditions and species. Know the basic structure of a growing root tip, and be able to identify and know the significance and function(s) of: root cap, apical meristem, ground meristem, procambium, protoderm, zone of cell division, zone of cell elongation, zone of maturation, endodermis, pericycle, Casparian strip, pith, cortex, epidermis, trichome, root hair, quiescent center, mucilage/mucigel, columella, promeristem Know the anatomy of a root in cross section, and be able to identify the layers and their function. Know the general characteristics and morphology of both V.A.M. and ectomycorrhizae. What is their relationship to the plant symbiont? Know the meaning/structure/significance of: vesicle, arbuscule, hyphae, Hartig net, cortex cell Know the three general routes of water movement across plant cells: apoplastic, symplastic, and tonoplastic. Know the general anatomy of the stele, and the different forms it can take. Know the different types of root specializations, and be able to recognize examples of them, even if you haven't heard the specific examples before. Understand the process of root colonization by nitrogen-fixing bacteria, and know the meaning/significance of: nodules, leghemoglobin, infection thread, Rhizobium, crop rotation, and refer to the diagram of the Nitrogen Cycle in Lecture Six (a new link) to review the Nitrogen Cycle and its steps. Know the meaning of nitrogen fixer, denitrifyer, nitrate, nitrite, ammonia. The Stem Know the general anatomy of the stem and its parts. Recognize the node, internode, apical bud, axillary bud, leaf axil, leaf scar. Know the locations and significance of the apical meristems, and the three primary meristems, as well as what tissues arise from each primary meristem. Recognize the anatomical structures of the monocot and dicot stems in cross sections, and their significance. What structures are different between root and stem? Know the meaning/significance/function of: lateral meristem, vascular cambium, cork cambium, secondary growth, annual growth rings, springwood, summerwood, heartwood, sapwood, determinate vs. indeterminate growth, annual versus perennial plants, true wood, herbaceous, lenticel Know the components of the bark, and be able to differentiate between bark, periderm, phloem, cork, cork cambium (and know which of these is a part of which). Know the various types of stem specializations, and be able to recognize even unfamiliar examples, if they are described. The Leaf Know the structure and significance of the following leaf parts and leaf-related structures: petiole, base, midrib, veins, margins, blade, apex, axil, axillary bud, stipule Know the basic forms of phyllotaxy, and be able to recognize illustrations of them, including: helical, distichous (alternate), opposite, opposite and dicussate, and whorled leaf arrangements Recognize the most common leaf shapes and the names of those shapes (in both simple and compound form, as applicable): pinnate, palmate, orbicular, ovate, obovate, cordate, reniform, acuminate, peltate, lobed Recognize the following vein morphologies: palmate, pinnate, reticulate, parallel Know the layers and locations of the various structures and internal layers of the leaf, including: cuticle, epidermis, pallisade parenchyma, spongy parenchyma, stomates, guard cells, trichomes, leaf gap adn leaf trace (on the stem), and the vascular tissue locations in the veins. Know the meaning/significance of hydrophyte, mesophyte, xerophyte Know the meaning/significance/function of minor veins, major veins, bundle sheath, bundle sheath extensions Know the general course of new leaf formation from the apical meristem, and the morphology, location, and function of: founder cells, leaf buttress, leaf primordia Recognize the various types of leaf specializations and their functions. Water Movement Know the meaning/significance of: bulk flow, water potential, solvent, solute, hydration shell, hypertonic, hypotonic, isotonic (=osmotic) solutions, diffusion, osmosis, dialysis Know what is meant by the cohesive and adhesive properties of water. Understand what may make a plant cell turgid or plasmoyze it. Know the general processes involved in transpiration. Know the meaning/significance of: shoot tension, root pressure, guttation, xylem sap, phloem sap. Know the roles played by each of the following in water movement through plants: Root hair, tonoplast, symplast, apoplast, plasmodesmata, endodermis, Casparian strips, stele, xylem, phloem, stomate, spongy mesophyll Know the meanings of embolism and cavitation. Know the meaning/significance of active transport, facilitated diffusion, proton pump, cotransport, source, sink Photosynthesis Understand how the Laws of Thermodynamics apply to photosynthesis, and the energy transductions that take place during carbon fixation. Know the meaning/significance (in terms of photosynthesis) of: enzyme, catalyst, substrate, active site, endergonic vs. exergonic reactions, catabolic vs. anabolic reactions, oxidation/reduction reactions. Know the characteristics of the electromagnetic spectrum, and particularly the wavelengths that drive photosynthesis. Know the meaning/significance of: pigment, chlorophylls, caroteinoids, accessory pigments, antenna pigments, primary electron acceptor, cytochromes, ATP, NADP+, NADP-H, transmission/absorption/reflection of photons Understand the general workings of photosystems I and II and their associated pigments, cyclic and non-cyclic electron flow and their products. Recall the general overall reactions of photosynthesis and cellular respiration. Know the general process of photorespiration and its significance. Know the general workings of both C4 and CAM metabolism, and what type of plants you'd expect to see doing this. Evolution Know the meaning/significance of hypothesis, theory, law, and what differentiates science from non-science. Know what is meant by adaptive, maladaptive, and neutral traits Know the meaning/significance of: microevolution, macroevolution, and know the five factors that can cause a population to evolve. Understand what is meant by Hardy- Weinberg equilibrium. Know the meaning/significance of: species, population, deme, gene pool Know Darwin's four tenets of evolution by natural selection, how to apply them, and how to recognize examples in nature of the "tenets in action." Understand the mechanisms of speciation, such as: allopatric, sympatric, peripatric, parapatric, as well as sympatric speciation via autopolyploidy and allopolyploidy. What is the significance of hybridization across Tragopogon species? Know the various types of prezygotic (temporal, ecological, geographic, mechanical, behavioral and gametic) and postzygotic (hybrid inviability, hybrid sterility and hybrid breakdown) isolating mechanisms and be able to recognize examples. Know what is meant by coevolution, the various types of symbiosis, adaptation, developmental plasticity, clines, ecotypes, the biological and morphological species concepts. Systematics and Taxonomy Know the meaning/significance of systematics, taxonomy, Systema naturae, Linnaeus, taxon. Know the levels of taxonomic hierarchy, from most to least inclusive. Know the meaning and significance of a taxon's name, rank, and content. Know the tools, data, and lines of evidence used by systematists to determine evolutionary relationships. Know the meaning/significance of monophyletic, polyphyletic, paraphyletic taxa, and be able to recognize descriptions of each. Know how to read a cladogram, and recognize the nodes representing common ancestors, extant taxa, and the features indicating characters unique to taxa on the tree. Don't miss the review session at 2:30pm on Wednesday, October 22 in room 166. Come prepared with questions. .
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