Biology 213: Biology of Plants, Review for Exam I

1. Why study Plants?

• Energy flow, carbon input, nitrogen input, biomass conversion, mineral elements, O₂ generation, water cycle, erosion, medicine, aesthetics/recreation, etc.
• Edible vaccines
• Tobacco Pharming
• Ethnobotany
• Elevated CO₂, global warming, deforestation, fossil fuel emissions, NDVI, etc
• Nitrogen oxide pollution and seeds
• Plants & CO2 Rich world by Bazzaz and C4 plants by Rowan Sage
• Video "power of plant", ethnobotany and natural plant products (herbivory deterrents)
• Questions concerning Medicinal Plants
• PowerPoint: Primary Metabolites in Plants, Secondary Metabolites in Plants

2. Plant Cells

• Ultrastructure of plant cells, middle lamella, intracellular spaces, cell walls, apoplast/symplast system, plasmalemma, protoplast, cytosol, hyaloplasm, peroxisome, glyoxysome, sphaerosome, granuals, tonoplast, chloroplast, mitochondrian, dictyosome, vesicles, microtubules, microfilaments, desmotubules, plasmodesmata, pits, ER, polyribosomes, vacuole, etc.
• Cell types & tissue types, parenchyma, sclerenchyma, collenchyma, tracheids, fibers , vessels, sieve tube members, companion cells, transfer cells, fusiform initials, ray initials, xylem, phloem, vascular cambium, procambium, cork cambium, procambium, etc.
• Apical meristems, basal meristems, ground meristem, dermal meristem, vascular meristem,

3. Body plan of a plant

• Shoot, root, apical meristem, nodes, internodes, axillary bud, flower, petiole, blade, leaf, tap root, primary root, secondary root, root hairs, cotyledon, tillers, basal meristem, etc.
• Seed, monocot, dicot, endosperm, seed coat, allueurone layer, coleoptile, coleorhiza, raph, hilum, micropyle, bran, wheat germ, embryo, radicle, scutellum, pericarp, etc.
• Seed germination, plant hormones, seasonal growth, leaf arrangements, "growth" in plants, etc.
• Primay growth and secondary growth.

4. Plant Leaves

• External anatomy and morphology of leaves. Monocot and dicot and gymnosperm
• Internal anatomy of leaves, epidermis, guard cells, stomatal complex, vascular bundles, bundle sheath, kranz anatomy, bundle sheath cells, mesophyll cells, palisade mesophyll, spongy mesophyll, substomatal cavity, monocot vs dicot leaves, bulliform cells, cuticle, cutin, trichomes, glandular hairs, etc.

5. Evolution of C4 Photosynthesis in plants

• Article and Seminar by Rowan Sage on C4 photosynthesis: Carboxylating enzyme "RuBISCO" in photosynthesis orginated in a geological age when there was a "reducing atmosphere" (high CO2 very low 02). When O2 accumulated in ancient atmosphere and CO2 decreased (by product of photosynthsis) photorespiration became a limiting factor and favored the evolution of C4 plants (20 MYA). Teeth of fossil horses in North America and grazing animals in Africa and South America deposit carbon in their enamel that indicates the time of origin of C4 plants (Figure 13, Cerling 1999). Tooth enamel contains well preserved fossil carbon and since C4 plants with PEP carboxylase activity do not descriminate against the heavier forms of isotopic carbon (C13) but C3 plants with RuBISCO carboxylase activity do, it is fairly easy to determine when fossil horses and other grazers switched from a C3 diet to a C4 diet.(carbon isotope level goes up, less negative, in Figure 13).
• "Kranz Anatomy" in the mosophyll of leaves is an indicator of C4 photosynthesis. There is only one example thus far of "single cell C4 photosynthesis", ask Libby Brooks.