Eukaryotic Microorganism Survey - Microbiology | BIOL 2230, Exams of Microbiology

Download Eukaryotic Microorganism Survey - Microbiology | BIOL 2230 and more Exams Microbiology in PDF only on Docsity! BIOL 2230 REEDER EUCARYOTIC MICROORGANISM SURVEY I. Eucaryotic Microorganisms: Algae, Fungi, Protozoa, Animal Helminths A. Algae 1. Representatives from both kingdoms: Protista and Monera 2. Contain one or more types of chlorophyll (a and b) plus additional pigmentation as carotenoids (yellow, orange, or red water insoluble hydrocarbons) and phycobilins (blue or red water-soluble protein-pigment structures) that may mask the chlorophylls a. algae group color dependent on their pigment ratio 3. Obtain energy via photosynthesis (same as that described for cyanobacteria and higher multicellular plants) 4. Lack vascular tissue (xylem and phloem) and airborne spores; lack multicellular reproductive structures 5. Widely distributed in nature: sufficient light, moisture, and nutrients required a. microscopic forms called phytoplankton float and/or swim on or near surface of both fresh and salt water; others may grow several hundred feet below b. most are aquatic, but some may be found terrestrially in damp soil 6. Vary in size and arrangement a. unicellular forms vary several micrometers to a centimeter in diameter b. multicellular colonial forms containing structurally identical cells or a complex of differentiated cells c. complex multicellular forms may grow greater than l00m in length possessing various specialized structures 7. Representative phyla: Nonpathogenic a. Chlorophyta (green algae): 1) possible ancestors of the first land plants (most similar to higher land plants) 2) unicellular, colonial, and filamentous (cells arranged end-to-end) forms 3) cell wall of cellulose and pectin storing reserve food as starch 4) most inhabit fresh water b. Euglenophyta (euglenids): 1) motile and unicellular; flagellated 2) Euglena: photosynthetic, but possessing many animal features a) no rigid cell wall b) inhabit soil and water c. Bacillariophyta (golden-brown algae): 1) storage of food as oil and contain large amounts of the carotene carotenoid 2) mostly unicellular 3) Diatoms: two portioned cell wall of silica with many intricate shapes a) abundant in both fresh and salt water comprising the phytoplankton d. Phaeophyta (brown algae): 1) predominant brown pigment (fucoxanthin) * 2) most complex of the algae a) kelps grow over l00m long e. Dinoflagellata: 1) contain a large representative group of unicellular, motile (two flagella) dinoflagellates a) armor-like appearance due to the interlocking plates of cellulose and pectin comprising their cell walls b) spins like a top through the water c) comprise the phytoplankton f. Rhodophyta (red algae): 1) unicellular to filamentous forms; some grow longer than lm 2) primarily marine 3) significant in the formation of reefs by the deposit of CaCO3 * 4) Gelidium provides for the production of agar 8. Algae's commercial and ecological significance: a. phytoplankton comprise the base of aquatic food chains b. production of atmospheric oxygen (02) c. used in fertilizers, food preparation, and agar production for use in microbiology B. Fungi 1. Lack chlorophyll and are generally nonmotile (except for some spore forms) 2. Unicellular (yeasts) to multicellular (long, branched, filamentous molds) forms 3. Some exhibit dimorphism (pathogenic forms: superficial and systemic mycoses); grow as unicellular yeasts under one set of conditions or as a filamentous mold under different circumstances a. Diphasic fungi: 1) yeast stage can grow in vivo (living tissue) or in vitro (glass tube) at 37o with filamentous form growing only in vitro at 25o C. *2) Most systemic mycoses are diphasic with the yeast stage found in living tissue a) Histoplasma capsulatum : Histoplasmosis b) Blastomyces dermatiditis: Blastomycosis 4. Most representatives are harmless saprophytes (decomposers of dead or decaying organic matter) requiring abundant moisture, organic matter supply and oxygen. 5. Yeasts: a. microscopically simple, independent cells usually round or ovoid b. are simpler cells than mold, but more complex and larger than bacteria c. all taxonomic fungal divisions contain yeasts d. most reproduce both sexually and asexually 1) usually asexually by budding 2) those yeasts able to reproduce sexually: two cells fuse forming a single, saclike ascus that will form one to eight spores e. widely distributed in nature, in water, soil, dust, and on many fruits and vegetables f. can grow facultatively using fermentation or utilize aerobic respiration; are a good source of nutrients being able to synthesize their own vitamins and proteins 6. Molds: a. Composed of long filaments of microscopic cells called hyphae (pl.), which may branch and intertwine to form a macroscopic filament mass called mycelium 1) each hypha may be divided into many different cells containing individual nuclei by septa (cross walls) resulting in septate hypha, or the hyphae may lack septa appearing as one long cell containing many nuclei referred to as coenocytic hypha b. hyphae cells vary in size with diameters of l0-20 um to as small as l um c. hyphal filament elongates by binary fission, but molds primarily reproduce by the formation of spores produced either sexually or asexually 1) spores are produced in large numbers and spread via wind currents or insects 2) spores will germinate if suitable conditions are found (source of organic matter, moisture, oxygen) and give rise to hyphal filaments typically forming a mycelia mass 7. Fungal Classification: a. Divisions: organized on the basis of the sexual reproductive structures (or lack of); *spore formation is primarily by asexual means 1) Zygomycota: fusion of opposite mating types of gametangia (n) result in a diploid zygote, which may form a resistant, black, thick walled zygospore (also 2n); forms a sporangium when it breaks dormancy to form spores; sporangia may be formed asexually as well; none are normal specific human pathogens, although Rhizopus and Mucor can be opportunistic causes of a serious, and often fatal pneumonia 2) Ascomycota (sac fungi): hyphae fusion of same or opposite mating types forms a fruiting body containing sexual spore producing sacs (asci); conidia are asexual spore-producing structures; large number of yeast representatives, as Saccharomyces; some species of Aspergillus and Penicillium; Peziza 3) Basidiomycota (club fungi): fruiting body (mushroom cap's) contains club-shaped sexual spore-producing structures; (basidium); asexual reproduction by fragmentation of conidia; few human diseases caused, but do result in several plant diseases (rusts and smuts of cereal grains); mushrooms, puffballs 4) Deuteromycota ("imperfect fungi"): no sexual stage has been observed in members of this class; many of the human fungal pathogens are represented: superficial infections of cosmetic concern, cutaneous infections of the nails, hair and stratum corneum of the skin, and sub-cutaneous and systemic infections resulting in debilitating and fatal diseases; Candida albicans, histoplasmosis, ringworm, dandruff, and athlete's foot; conidia for asexual spore production