Exam 4 Flashcards
Phylogeny
Establish an evolutionary history
Carlaus Linnaeus
2 kingdom system: plantae and animalia
Carl Woese
3 domain system (eukarya, bacteria, archaea) based on variation in cellular composition and rRNA sequences
Prokaryote, no peptidoglycan, branched carbon chains, lacking rRNA loop and Arm of tRNA
Archaea
Prokaryotic, peptidoglycan, straight carbon chains ESTER linked, rRNA loop and arm of tRNA present
Bacteria
Eukaryotic, straight carbon chains Ester linked, no rRNA loop, Arm of tRNA present
Eukarya
16 rRNA gene
Molecular tool to determine phylogeny and group organisms into taxa
Protoebacteria
Largest and most diverse phylum of GRAM-NEGATIVES, includes purple a oxygen Uc phototrophs
Proteobacteria classes
Alpha, beta, gamma, delta, epsilon
Proteobacteria class: alpha
Unusual morphologies
Human pathogens genus: Rickettsia
Ecologically significant genus: bradyrhizobium, rhizobium, nitrobacter, agrobacterium
Distinctive features genus: caulobacter & hyphomicrobium
Proteobacteria class: Beta
Utilize nutrients diffusing from areas of decomposition
Human pathogens genus: bordetella, neisseria
Ecologically significant genus: thiobacillus
Distinctive features genus: Shaerotillus
Proteobacteria class: Gamma
Largest class; greatest variety of physiology; includes enteric bacteria
Non enteric bacteria (gamma class)
Human pathogens genus: francisella, pseudomonas, vibrio
Ecologically significant genus: Beggiatoa, azotobacter & azomonas, thiomargarita, pseudomonas
Distinctive features: pseudomonas
Enterobacteriales or Entrics (gamma class)
Facultative anaerobic bacilli; peritrichous flagella possible; common in animal microbiota
Protoebacteria class: delta
Some predatory to other bacteria
Ecologically significant: desulfovibrio
Distinctive features: Bdelovibrio, myxococcus
Preteobacteria class: epsilon
Microaerophilic flagellated helical or vibrio cells
Human pathogens: campylobacter, helicobacter
Cyanobacteria
Gram negatives, large, diverse phylum unicellular or filamentous morphology; gliding motility or gas vacuoles; fix nitrogen and photosynthetic
Spirochetes
Gram negative, coiled morphology; axial filaments
Chlamydiae
Gram negatives, no PTG in cell wall; intracellular with very complex life cycle
Human pathogen: chlamydia, chlamydophila
Gram positive bacteria phyla
Firmicutes (low C + G) - bacteria w/o cell walls and endospore formers
Actinobacteria (high C + G) - acid fast bacteria and actinomycetes
Archaea
Most ecologically diverse of the three domains. Psychrophiles and hyperthermophiles, halophiles, acidophiles, methanogens. Most abundant in moderate habitats
Crenarchaeota
Widest range of temperature, hyperthermophiles, mesopholes, psychrophiles
Thaumarchaeota
Mesophillic heterotrophs and sulfur oxidizers; ammonia oxidizers
Euryarchaeota
Shows the greatest range of metabolism; methanogens, halophiles, some thermophiles
Protista (eukaryotic kingdom)
Photosynthetic protists - algae
Flagellates, ciliates, amoeboids, sporozoans - Protozoa
Water molds and slime molds - funguslike
Paramecium
Ciliates
Giardia
Flagellates
Entamoeba
Amoebids
Plasmodium
Sporozoans (non-motile)
Animalia (eukaryotic kingdom)
Multicellular, heterotrophic eukaryotes
Helminths (parasitic worms) - complex life cycle involving hosts
Helminths (parasitic worms)
Many are Intestinal parasites
Platyhelminths (flatworms)
Nematodes (round worms)
Example of Platyhelminthes (flatworms)
Trematodes (flukes)
Cestodes (tapeworms)
Example of Nematodes (round worms)
Hookworms: ancylostoma & necator Ascaris lumbricoides
Pinworms (Enterobius vermicularis)
Trichinella spiralis
Whipworm (Trichuris trichiura)
Fungi (eukaryotic kingdom)
Mycology
Avascular, typically non-motile, unicellular (nonmycelial) or multicellular, aerobes, anaerobes, or facultative anaerobes, chemoorganoheterotrophs
Chemoorganoheterotrophs
Saprophytes and parasites
Yeasts
Unicellular
Budding and Saccharomyces (bakers yeast)
Opportunistic pathogens
Benefits of Fungi
Decomposers, plant associated with mycorrhizae, food, pharmaceutical
Pathogenic fungi (mycoses)
Stachybotrys - hemorrhagic pneumonia & mycotoxins
Aspergillus - mildew & aspergillosis
Pneumocystis - “red flag” in AIDS
Candida - thrush, diaper rash, yeast infection
Cryptococcus - cryptococcosis & meníngoencephalitis
Edible Fungi
Saccharomyces - fermentation of bread and alcohol
Torulopsis - protein supplements
Aspergillus - citric acid
Trichoderma - fruit juice production
Pharmaceutical fungi
Penicillium and Cephalosporium - antibiotics
Tolypocladium - cyclosporine
Penicillium and Aspergillus - statins
Genetically engineered yeast - Vaccines
Multicellular fungi
Absorptive nutrition
Hyphae generate mycelium
Cell walls contain chitin
Membranes contain sterol ergosterol
Vegetative hyphae
Functions to obtain nutrients
Ariel hyphae
Functions to produce reproductive spores sexually and asexually
Zygomycota
Zugospores
Black bread molds (aseptate)
Ascomycota
Ascus
Sac fungi
Basidiomycota
Basidia
Club fungi
Ecological roles of fungi
1) Formation of mycorrhizae that extend the root systems of plants
2) recycling biomass of wood and leaves
3) digestion of lignin, a component of wood
Common traits shared by most multicellular fungi
1) absorptive nutrition
2) hyphae production
3) classified by sexual reproductive strategy
4) chitinous cell walls
Asexual fungal spores produced inside a sac at the end of reproductive (aerial) hyphae
Sporangiospore
Mycelium (quiz question)
Visible mass of hyphae
Hyphae (quiz question)
Multinucleate cell filaments
Sexual reproductive process of fungi
Used to classify fungi into phyla
Polysaccharide found in the cell wall of many fungi
Chitin
Asexual reproduction (spore production) of fungi
Used to identify fungi
T/F Members of the Zygomycota fungal phylum (division) commonly form mycorrhizal associations with the roots of many plants
False
The term “protist” includes all these single cell eukaryotic organisms
1) ciliates
2) algae
3) flagellates
4) amebas
NOT YEAST
Pinworms, which are common human parasites, are a round worms and are considered a
Nematode
T/F Protozoans were once classified based on their mode of motility but are currently placed into taxa based on SSU rRNA sequences
True
T/F Fungi can cause some very serious diseases in humans but most fungi are actually opportunistic pathogens
True
The group of microbes that includes ciliates, flagellates, and non-motile sporozoans is known as
Protozoan
