Transcript Jan 20
Plan C We will pick a problem in plant biology and see where it takes us. 1. Phytoremediation 2. Plant products 3. Biofuels 4. Effects of seed spacing on seed germination 5. Climate/CO2 change 6. Stress responses/stress avoidance 7. Improving food production 8. Biotechnology 9. Plant movements 10. Plant signaling (including neurobiology) 11. Flowering? 12. Something else? Plan C 1.Pick a problem 2.Pick some plants to study 3.Design some experiments 4.See where they lead us Plan C Grading? Combination of papers and presentations •First presentation: 5 points •Research presentation: 10 points •Final presentation: 15 points •Assignments: 5 points each •Poster: 10 points •Intermediate report 10 points •Final report: 30 points ALTERNATIVES •Paper(s) instead of 1 or two presentations •Research proposal instead of a presentation •One or two exams? BIO 369 - Resource and Policy Information Instructor: Dr. William Terzaghi Office: SLC 363/CSC228 Office hours: MW 11-12 and T 1-2 in SLC 363, R 1-2 & F 11-12 in CSC228, or by appointment Phone: (570) 408-4762 Email: [email protected] Course webpage: http://staffweb.wilkes.edu/william.terzaghi/bio369.html Vegetative Plants 3 Parts 1. Leaf 2. Stem 3. Root Vegetative Plants 3 tissue types 1. Dermal 2. Ground 3. Vascular • Plant Development Cell division = growth • • Plant Development Cell division = growth Determination = what cell can become • • • Plant Development Cell division = growth Determination = what cell can become Differentiation = cells become specific types • • • • Plant Development Cell division = growth Determination = what cell can become Differentiation = cells become specific types Pattern formation: developing specific structures in specific locations • • • • • Plant Development Cell division = growth Determination = what cell can become Differentiation = cells become specific types Pattern formation Morphogenesis: organization into tissues & organs Plant Development umbrella term for many processes • embryogenesis Plant Development umbrella term for many processes • Embryogenesis • Seed dormancy and germination Plant Development umbrella term for many processes • Embryogenesis • Seed dormancy and germination • Seedling Morphogenesis Plant Development umbrella term for many processes • Embryogenesis • Seed dormancy and germination • Seedling Morphogenesis • Transition to flowering, fruit and seed formation Plant Development umbrella term for many processes • Embryogenesis • Seed dormancy and germination • Seedling Morphogenesis • Transition to flowering, fruit and seed formation Many responses to environment Plant Development Umbrella term for many processes Unique features of plant development • Cell walls: cells can’t move: Must grow towards/away from signals Plant Development Umbrella term for many processes Unique features of plant development • Cell walls: cells can’t move: must grow instead • Plasticity: plants develop in response to environment Unique features of plant development • Cell walls: cells can’t move • Plasticity: plants develop in response to environment • Totipotency: most plant cells can form an entire new plant given the correct signals • • • • Unique features of plant development Cell walls: cells can’t move Plasticity: plants develop in response to environment Totipotency: most plant cells can form an entire new plant given the correct signals Meristems: plants have perpetually embryonic regions, and can form new ones • • • • Unique features of plant development Cell walls: cells can’t move Plasticity: plants develop in response to environment Totipotency: most plant cells can form an entire new plant given the correct signals Meristems: plants have perpetually embryonic regions, and can form new ones • No germ line! Unique features of plant development • Meristems: plants have perpetually embryonic regions, and can form new ones • No germ line! Cells at apical meristem become flowers: allows Lamarckian evolution! Unique features of plant development • Meristems: plants have perpetually embryonic regions, and can form new ones • No germ line! Cells at apical meristem become flowers: allows Lamarckian evolution! • Different parts of the same 2000 year old tree have different DNA & form different gametes Endomembrane system Common features • derived from ER Endomembrane system Common features • derived from ER • transport is in vesicles Endomembrane system Common features • derived from ER • transport is in vesicles • proteins & lipids are glycosylated Endomembrane system Organelles derived from the ER 1) ER 2) Golgi 3) Vacuoles 4) Plasma Membrane 5) Nuclear Envelope 6) Endosome 7) Oleosomes ER Network of membranes t/out cell 2 types: SER & RER SER tubules that lack ribosomes fns: 1) Lipid syn 2) Steroid syn 3) drug detox 4) storing Ca2+ 5) Glycogen catabolism RER Flattened membranes studded with ribosomes 1˚ fn = protein synthesis -> ribosomes are making proteins ER SER & RER make new membrane! GOLGI COMPLEX Flattened stacks of membranes made from ER GOLGI COMPLEX Individual, flattened stacks of membranes made from ER Fn: “post office”: collect ER products, process & deliver them Altered in each stack GOLGI COMPLEX Individual, flattened stacks of membranes made from ER Fn: “post office”: collect ER products, process & deliver them Altered in each stack Makes most cell wall carbohydrates! GOLGI COMPLEX Individual, flattened stacks of membranes made from ER Fn: “post office”: collect ER products, process & deliver them Altered in each stack Makes most cell wall carbohydrates! Protein’s address is built in VACUOLES Derived from Golgi Fns: 1) digestion a) Organelles b) food particles VACUOLES Fns: 1) digestion a) Organelles b) food particles 2) storage VACUOLES Fns: 1) digestion a) Organelles b) food particles 2) storage 3) turgor: push plasma membrane against cell wall VACUOLES Vacuoles are subdivided: lytic vacuoles are distinct from storage vacuoles! Endomembrane system Organelles derived from the ER 1) ER 2) Golgi 3) Vacuoles 4) Plasma Membrane Regulates transport in/out of cell Endomembrane system Organelles derived from the ER 1) ER 2) Golgi 3) Vacuoles 4) Plasma Membrane Regulates transport in/out of cell Lipids form barrier Proteins transport objects & info Endomembrane System 5) Nuclear envelope: regulates transport in/out of nucleus Continuous with ER Endomembrane System 5) Nuclear envelope:regulates transport in/out of nucleus Continuous with ER Transport is only through nuclear pores Endomembrane System 5) Nuclear envelope:regulates transport in/out of nucleus Continuous with ER Transport is only through nuclear pores Need correct signal & receptor for import Endomembrane System 5) Nuclear envelope: regulates transport in/out of nucleus Continuous with ER Transport is only through nuclear pores Need correct signal & receptor for import new one for export Endomembrane System Nucleus: spherical organelle bounded by 2 membranes and filled with chromatin = mix of DNA and protein Endomembrane System Nucleus: spherical organelle bounded by 2 membranes and filled with chromatin fns = information storage & retrieval Ribosome assembly (in nucleolus) Endomembrane System Endosomes: vesicles derived from Golgi or Plasma membrane Fn: sorting materials & recycling receptors Endomembrane System Oleosomes: oil storage bodies derived from SER Surrounded by lipid monolayer! Endomembrane System Oleosomes: oil storage bodies derived from SER Surrounded by lipid monolayer! • filled with lipids: no internal hydrophobic effect! endosymbionts • derived by division of preexisting organelles • no vesicle transport •Proteins & lipids are not glycosylated endosymbionts •derived by division of preexisting organelles • little exchange of membranes with other organelles 1) Peroxisomes (microbodies) Peroxisomes (microbodies) 1 membrane Peroxisomes (microbodies) found in (nearly) all eukaryotes 1 membrane Fn: 1) destroy H2O2, other O2-related poisons Peroxisomes Fn: 1. destroy H2O2, other O2-related poisons 2. change fat to CH2O (glyoxysomes) Peroxisomes Fns: 1. destroy H2O2, other O2-related poisons 2. change fat to CH2O (glyoxysomes) 3. Detoxify & recycle photorespiration products Peroxisomes Fn: 1. 2. 3. 4. destroy H2O2, other O2-related poisons change fat to CH2O (glyoxysomes) Detoxify & recycle photorespiration products Destroy EtOH (made in anaerobic roots) Peroxisomes ER can make peroxisomes under special circumstances! e.g. peroxisome-less mutants can restore peroxisomes when the wild-type gene is restored endosymbionts 1) Peroxisomes (microbodies) 2) Mitochondria Mitochondria Bounded by 2 membranes Mitochondria 2 membranes Smooth OM Mitochondria 2 membranes Smooth OM IM folds into cristae Mitochondria -> 4 compartments 1) OM 2) intermembrane space 3) IM 4) matrix Mitochondria matrix contains DNA, RNA and ribosomes Mitochondria matrix contains DNA, RNA and ribosomes Genomes vary from 100,000 to 2,500,000 bp, but only 40-43 genes Mitochondria matrix contains DNA, RNA and ribosomes Genomes vary from 100,000 to 2,500,000 bp, but only 40-43 genes Reproduce by fission Mitochondria matrix contains DNA, RNA and ribosomes Genomes vary from 100,000 to 2,500,000 bp, but only 40-43 genes Reproduce by fission IM is 25% cardiolipin, a bacterial phospholipid Mitochondria Genomes vary from 100,000 to 2,500,000 bp, but only 40-43 genes Reproduce by fission IM is 25% cardiolipin, a bacterial phospholipid Genes most related to Rhodobacteria Mitochondria Fn : cellular respiration -> oxidizing food & supplying energy to cell Also make many important biochemicals Mitochondria Fn : cellular respiration -> oxidizing food & supplying energy to cell Also make important biochemicals & help recycle PR products Mitochondria Fn : cellular respiration -> oxidizing food & supplying energy to cell Also make important biochems & help recycle PR prods • Have extra oxidases: burn off excess NADH or NADPH? endosymbionts 1) Peroxisomes 2) Mitochondria 3) Plastids Plastids Chloroplasts do photosynthesis Amyloplasts store starch Chromoplasts store pigments Leucoplasts are found in roots Chloroplasts Bounded by 2 membranes 1) outer envelope 2) inner envelope Chloroplasts Interior = stroma Contains thylakoids • membranes where light rxns of photosynthesis occur •mainly galactolipids Chloroplasts Interior = stroma Contains thylakoids • membranes where light rxns of photosynthesis occur •mainly galactolipids Contain DNA, RNA, ribosomes Chloroplasts Contain DNA, RNA, ribosomes 120,000-160,000 bp, ~ 100 genes Chloroplasts Contain DNA, RNA, ribosomes 120,000-160,000 bp, ~ 100 genes Closest relatives = cyanobacteria Chloroplasts Contain DNA, RNA, ribosomes 120,000-160,000 bp, ~ 100 genes Closest relatives = cyanobacteria Divide by fission Chloroplasts Contain DNA, RNA, ribosomes 120,000-160,000 bp, ~ 100 genes Closest relatives = cyanobacteria Divide by fission Fns: Photosynthesis Chloroplasts Fns: Photosynthesis & starch synth Photoassimilation of N & S Chloroplasts Fns: Photosynthesis & starch synth Photoassimilation of N & S Fatty acid & some lipid synth Chloroplasts Fns: Photosynthesis & starch synth Photoassimilation of N & S Fatty acid & some lipid synth Synth of ABA, GA, many other biochem Chloroplasts & Mitochondria Contain eubacterial DNA, RNA, ribosomes Inner membranes have bacterial lipids Divide by fission Provide best support for endosymbiosis