Chapter 27, 28, 31 Topic Coverage - Biology PDF

**Chapter 27 Bacteria and Archaea** defining **Gram Stain** - Gram Positive = Thick peptidoglycan - Stain blue or purple - Gram Negative = Thin peptidoglycan but contains a toxic outer membrane - Stain red or pink - More antibiotic resistance **Motility and Irreducible complexi...

**Chapter 27 Bacteria and Archaea** defining **Gram Stain** - Gram Positive = Thick peptidoglycan - Stain blue or purple - Gram Negative = Thin peptidoglycan but contains a toxic outer membrane - Stain red or pink - More antibiotic resistance **Motility and Irreducible complexity** - **Motility** - Taxis = the ability to move toward or way from stimulus - Chemotaxis = movement toward or away from chemical stimulus - **Irreducible complexity** - System with multiple interacting parts would not function if one of the parts were removed (flagella) **F-Factor (should be review) - gaining new genetic information** - **Rapid Reproduction and Mutation** - Prokaryotes reproduce by binary fission - Mutation rates during binary fission are low - Short generation time allows prokaryotes to evolve quickly - **Genetic Recombination (Horizontal Gene Transfer)** - Transformation = Takes DNA from environment - Transduction = Bacteriophage transfers DNA from one bacterium to another - Conjugation = Cell to Cell contact transfer of DNA **Nutritional modes and role of oxygen** - **Nutritional Modes** - Phototrophs = energy from light - Chemotrophs = energy from chemicals - Autotrophs = Require CO2 as carbon source - Heterotrophs = Organic nutrients to make organic compounds - **Role of Oxygen** - Obligate Aerobes requires O2 for cellular respiration - Obligate anaerobes use fermentation or anaerobic respiration, poisoned by O2 - Facultative anaerobes can survive w/ or w/o O2 - x **Metabolic Cooperation** - **Nitrogen Metabolism** - Convert atmospheric nitrogen (N2) to ammonia (NH3) - **Metabolic Cooperation** - Heterocyst's exchange metabolic products - Photosynthetic cells and nitrogen fixing cells exchange goods - Biofilms = surface coating colonies - Corrosion, Tooth decay, antibiotic resistant infection - Sulfate and Methane consuming bacteria on the ocean floor use each other's waste products x x **Prokaryotic diversity** **Proteobacteria - 5 groups =** Gram (-) - Alpha Proteobacteria = Nitrogen fixation - Ex) Rhizobium inside a root cell - Beta Proteobacteria = nitrogen cycling - Ex) Neisseria, Nitrosomonas - Gamma Proteobacteria = Largest and most diverse class including many human pathogens - Ex) Thiomargarita containing sulfur waste, E. Coli, Salmonella - Delta Proteobacteria = Sulfate Reduction and unique predatory behavior - Ex) Fruiting bodies Chondromyces, Myxobacteria - Epsilon Proteobacteria = Animal hosts, often GI tract - Ex) Helicobacter x **Bacteria - 4 groups** - Chlamydia's = survive only within animal cells for ATP. - Ex) Chlamydia trachomatis -- cause of blindness - Spirochetes = rotating, internal, flagellum. Free living - Ex) Treponema pallidum - Cyanobacteria = Only plantlike, oxygen generating photosynthesis - Ex) Phytoplankton - Gram (+) (Actinomycetes) = High G+C in DNA, produce antibiotics x **Extremophiles - Archaea - and comparison chart** - Extreme Halophiles = highly saline environment - Extreme Thermophiles = Very hot environments - Methanogens = live in swamps and marshes, produce methane as waste product - x **Ecological interactions** - Symbiosis = larger host and smaller symbiont - Mutualism = Both symbiotic organism benefit - Commensalism = One benefit while neither harming nor helping the other - Parasitism = Parasite arms but does not kill its host - Exotoxins = Secreted and cause disease - Endotoxins = Release only when bacteria die and cell wall break down - Bioremediation = Use of organism to remove pollutants from environment x **Chapter 28 Protists** Definition Notes\ - Protists = Eukaryotes\ - Most protists are unicellular Four supergroups **Excavates** (Cytoskeleton) x **Diplomonads** -- Reduced mitochondria (Mitosomes) - Anaerobic pathway - Two equal sized nuclei and multiple flagella **Parabasalids** -- Reduced mitochondria (Hydrogenosomes) - Generate some energy anaerobically **Euglenozoans** (kinetoplastids, euglenids) -- Spiral or Crystalline rod inside flagella - Kinetoplastids = single mitochondrion w/ ass of DNA (Kinetoplast) - Euglenids = one or two flagella that emerge from a pocket at one end of the cell - Both autotrophic and heterotrophic x **SAR** x **Stramenopiles --** Most have hairy flagellum with smooth flagellum x **Diatoms --** Unicellular algae with a unique two-part, glass like wall of silicon dioxide - Removes CO2 from atmosphere and pumps it to the ocean floor x **Golden Algae -** Biflagellated each at one end - Photosynthetic and mixotrophs - Unicellular x **Brown algae --** Largest and most complex - Multicellular and commonly called seaweeds - Holdfast (Anchor), Stipe (Stem), Blades (Leaflike) x **Alternation of generations --** Alteration of multicellular haploid and diploid forms - Heteromorphic -- structurally different - Isomorphic -- look similar x **Alveolates --** Membrane enclosed sacs under plasma membrane x **Dinoflagellates --** Two flagella, each cell reinforced by cellulose plate - Cause toxic red tides called dinoflagellate blooms - Aquatic phototrophs, mixotrophs, heterotrophs x **Apicomplexans --** Parasites of animals, spread through their host as infectious cells (sporozoites) - One end of apex contains organelles specialized for penetrating host cells and tissues - Sexual and Asexual stages that require two or more different host species for completion x **Ciliates --** Use of cilia to move and feed, large macronuclei and small micronuclei - Conjugation x **Rhizarians --** Mostly ameobas, move and feed by pseudopodia x **Radiolarians --** Symmetrical internal skeletons, made of silica - Use pseudopodia to engulf microorganism through phagocytosis x **Forams --** Calcium carbonate, multichambered shells (test) - Endosymbiotic algae (two organism live together with one inside the other) x **Cercozoans --** Amoeboid and flagellated protists w/ threadlike pseudopodia, mostly heterotrophs x Nutrient acquisition A. Apicomplexans B. euglenozoans - Predation, parasitism, photoautotroph, also dead/decaying organic matter C. Dinoflagellates - Ingesting prey, transporters D. Entamoebas - Parasitic Structural/Anatomical components A. diatoms B. foraminiferans C. ciliates D. dinoflagellata E. brown algae x Red algae and green algae - transitional to plants - Similar between algae and plants (analogous structures) **Red Algae (Archaeplastida) --** Red color from pigment called phycoerythrin mask the green of chlorophyll - Multicellular - Most abundant, found in sushi (seaweed) **Green Algae** **(Archaeplastida) --** Plants descended from green algae - Paraphyletic group - Charophytes = land plants - Chlorophytes = fresh water x **Unikonts - transitional to fungi and animals** - Protist that are closely related to fungi and animals x **Amoebozoans --** Amoeba that have lobe or tube shaped, rather than threadlike pseudopodia **Slime Molds --** Slime molds and fungi result of convergent evolution **Plasmodial Slime Molds --** single cell organism - Sexual and Asexual reproduction **Cellular Slime Molds --** Form Multicellular aggregates - Asexual reproduction **Tubulinids --** lobe or tube-shaped pseudopodia - Unicellular protist - Heterotrophic & actively seek and consume bacteria and other protists **Entamoebas --** Parasites of vertebrates and some invertebrates x **Opisthokonts --** include animals, fungi, and several groups of protists x **Symbiosis and Photosynthesis** - **Symbiosis** - Dinoflagellates nourish coral polyps that build reefs - Wood digesting protists inhabit the gut of termites - **Photosynthesis** - Producers that obtain energy from the sun - Biomass of photsynthetic protist have declined as sea surface temperature increase - Warm surface water acts as barrier to upwelling - Can lead to effects in Marine ecosystem, fishery yields, global CO cycle **Chapter 31 Fungi** **Nutrition** - Fungi are heterotrophs (takes food from other organism) - Decomposers, Parasites, Mutualists (Lifestyles) **Body Structure** - Multicellular filaments and single cells (Yeasts) - Can grow either filaments or yeasts; or both - Consist of mycelia - Hyphae, network of branches for absorption - Divide into cells by septa, with pores allowing cell to cell movement - Coenocytic fungi lack septa, continuous cytoplasmic - Haustoria (specialized hyphae) = penetrate the tissues of their host - Fungal cell wall has chitin - Mycorrhizae = mutually beneficial relationship between fungi and plant roots - Ectomycorrhizal fungi = sheaths of hyphae over a root and grow into extracellular spaces of root cortex - Arbuscular mycorrhizal fungi - Hyphae through cell wall of root and into tubes - Mycorrhizal fungi deliver phosphate ions and minerals to plants - Colonize soil by dispersal of haploid cell (spores) **Reproduction - sexual (plasmogamy and karyogamy) and asexual** **Phyla** x **Chytrids --** Freshwater, Terrestrial, Marine - Decomposers, Parasites or mutualist - Diverged early in fungal evolution - Unique in having flagellated spores (zoospores) x **Zygomycetes --** Parasites or commensal symbionts of animals - Form filamentous hyphae and reproduce asexually via nonflagellated spores - Metabolically inactive and resistant to freezing and drying - Site of karyogamy and then meiosis x **Glomeromycetes --** Form arbuscular mycorrhizae - Were considered zygomycetes x **Ascomycetes --** Marine, Freshwater, Terrestrial - Produce sexual spores in asci, contained in fruiting bodies (ascocarps) - Plant pathogens, decomposers and symbionts - Reproduce asexually spores (conidia) - Produce at the tip of specialized hyphae (conidiophores) x **Basidiomycetes --** Mushrooms, puffballs, and shelf fungi - Basidium, clublike structure - Decomposer of wood - Can produce mushrooms quickly - Produce fairy rings x **Ecological roles (Fungi)** - Decomposers - Efficient decomposers of organic material such as cellulose and lignin - Mutualist - Relationships w/ plants, algae, cyanobacteria, and animals - Fungus-Plant Mutualism - Endophytes make toxins that deter herbivores and defend against pathogens - Fungus-Animal Mutualism - Help break down plant material in guts - Lichens - Symbiotic association between photosynthetic microorganism and fungus x