Microbiology Exam 1 Overview

Microbiology Exam 1 (Chapters 1, 3-5) Microbiology Specialized area of biology that deals with organisms ordinarily too small to be seen without magnification. Microorganisms A living thing ordinarily too small to be seen without magnification. Classification Orderly arrangement of organisms into groups. Nomenclature System of assigning names. Binomial nomenclature Two-name system of naming organisms (Latin, Greek). Two names: Genus, species. It's always underlined or italicized. Genus first letter always capitalized, species not capitalized. Once it's been mentioned, the genus name can be shortened. Acellular organisms Viruses. Exist without a cellular structure. Cellular organisms Prokaryotes and Eukaryotes. Prokaryotes Organisms whose genetic material is not enclosed in membrane and lack specific organelles including a nucleus (bacteria). Eukaryotes Organisms whose genetic material is enclosed in nucleus (fungi, protozoa, algae). Prokaryotes versus Eukaryotes Prokaryotic cells are smaller than eukaryotic cells, and in addition to lacking a nucleus, they lack other complex internal compartments called organelles. All prokaryotes are microorganisms while only some eukaryotes are microorganisms (including algae, protozoa, molds and yeasts- and even anthropods). Binary fission The way bacteria reproduce. Splitting of a parent cell into two equal parts. Mycology The study of fungi. Phycology The study of simple photosynthetic eukaryotes (algae) ranging from single celled forms to large seaweeds. Pathogen Disease causing agents. Genetic engineering Manipulates the genetics of microbes, plants, and animals for the purpose of creating new products and genetically modified organisms. Recombinant DNA Switch DNA from one organism to another to design new organisms. Lactic acid bacteria Dairy products, yogurt and cheese. Curds Solid chunks of day old milk, (fats and proteins etc. used in cheese) and whey (mostly water). A gallon of milk yields only about 1.25 pounds of cheese (weight lost is water). Whey Liquid part of day old milk, mostly water. Rennin Turn caseinogens to casein. Curdling Products cause milk to separate into curds (the milk solids, fats, proteins, etc. Scientific method Approach taken by scientists to explain a certain natural phenomenon. Hypothesis A tentative explanation or statement to account for what is observed or measured. Theory Hypothesis backed by growing data. Spontaneous generation Life can rise from nonliving material. Cell theory All things are made of cells. Biogenesis the production of living organisms from other living organisms Fermentation Organisms convert sugar into alcohol or acid (vinegar). Using bacterial/fungal enzymes, convert food substrate from one form to another. Aid in slow food spoilage. Foods use it for flavor and other 1 / 12 properties. Fermentation products include Lactic acid, acetic acid, yeast, etc. Pasteurization To kill organisms by heat, some spoiling agents still stay. Germ theory of disease Theory that microbes can invade other organisms and cause diseases. Koch's postulates Set of procedures to determine if a microbe causes a certain disease. Verified the germ theory of disease. Aseptic technique Aimed at reducing microbes in a medical setting and preventing wound infections. Lister proposed the idea of aspetic techniques and the importance of hand washing and equipment sterilization. Chemotherapy Treatment of disease by the use of chemical substances. Now problem with drug resistance. Synthetic drugs Chemical substances made in a lab. Antibiotics Chemical substance made by microbes. General sizes of macroscopic organisms? 1 mm Size of Microscopic organisms? 1 um to 100 um Size of Viruses? 10 nm to 100 nm What are the 3 domains used in the Woese-Fox system of classification? Bacteria, Archaea, Eukarya. Which domain are fungi members of? Eukarya Which domain are Protozoa? Eukarya Which domain are Algae? Eukarya Which domain are E. coli? Bacteria Which domain are Viruses? Neither Viruses Neither prokaryote or eukaryote; acellular. Very small (nm). Need an electron microscope to see them. Parasite. Core/caspid contains nucleic acids and a protein coat. Some envelope around caspids. Bacteria Prokaryote. All are microbes. Has a cell wall made up of Eubacteria peptidoglycan. Absorb nutrition. Reproduce by binary fission. Unicellular. Commonly found in biofilms. Algae Unicellular, some are multicellular. Reproduce asexually and sexually. Nutrition by photosynthesis. Cell wall made of cellulose. Fungi Some are unicellular, some are multicellular. Nonmotile. Reproduce by asexual and sexual reproduction. Cell wall made of chitin. Fungi digest outside then ingest, absorb by release enzymes into environment. Cell membrane made of ergosterol instead of cholesterol. Protozoa Unicellular. Reproduce sexually and asexually. No cell wall. Absorb nutrition. Use pseudopods, cilia and flagella for motility. Name 3 cellular structures protozoa use for locomotion Pseudopods, flagella, cilia. Be familiar with the ways that microorganisms are beneficial Part of food chain. Beneficially interact with other organisms in nature. Normal flora- vitamins. Help initial digestion of nutrients in rumen of stomach (primarily cellulose). Production of oxygen. Antibiotics, vaccine, medical advances). Be familiar with the ways that microbes affect the world. Found everywhere, part of the ecosystem (make greenhouse gasses, soil formation, mineral extraction), Nutrient recycling (CO2 and Nitrogen fixation). Decomposition. Interactions with other organisms- pathogens or beneficial. Mycology Study of fungi. Protozoology Study of protozoa. 2 / 12 Virology Study of viruses. Phycology Study of simple photosynthetic eukaryotes. Morphology Study of detailed structure of microorganisms. Physiology Study of Microbial function. Taxonomy Classification/naming/ identification. Bacteriology Study of Bacteria. Microbial ecology Study of relationship between microbes and environment. What general metabolic process used by microbes aids in food production? Fermentation. Yeast A type of microscopic fungi that makes bread rise and ferments sugar to make alcoholic beverages. Why can cheeses have different tastes and properties even Different microbes give different flavors by different fermentation though they are all made from the lactic acid fermentation of milk? end products. What molecule found in yogurt makes it taste tart? Acetaldehyde. What causes holes to form in swiss cheese? Fermenting the remaining lactose & producing carbon dioxide bubbles in the cheese. How does wine become sour? Wine exposed to air and bacteria form acetic acid. Why did the study of microorganisms not officially begin until the 1500s? Microscope not developed until the 1500's. Hooke Coined the term "cell." Needham Spontaneous bacteria in heated broth with cover. Redi No flies from meat. Pasteur S-neck flask and aseptic technique. Vaccine for cholera and rabies. Schwann & Schleiden All living things are made of cells. Virchow Living cells come from preexisting cells. Lister Use carbolic acid sprayer (phenol) to sterilize surgical wounds and instruments to reduce infection. Semmelweis Hand washing during child birth by doctors. Jenner Vaccine for smallpox. Ehrlich Coined term "chemotherapy." Used the first synthetic chemo that did not damage tissue: Magic bullet. Flemming Penicillin from mold. Venter & Smith Complete sequence of bacterial genome. What are the three theories of how life emerged discussed in lecture? Cell theory, biogenesis, spontaneous generation. What were the major accomplishments of the Golden Age of Microbiology? Fermentation Pasteurization, Germ Theory, Vaccination. Why does milk spoil even if it is pasteurized? Some spoilage organisms stay. Name two foods that are pasteurized besides milk Eggs, Honey. What are the two types of chemotherapy? Synthetic drugs and antibiotics. Sterile Complete absence of viable microbes. Aseptic Prevent infection. Inoculation Cultivating (CULTURING) microorganisms by introducing a sample (INOCULUM) into a container of nutrient medium. Culture Observable growth that appears in or on the medium (cloudiness, colony) 3 / 12 Incubation The medium is placed in a temperature-controlled chamber (INCUBATOR) to allow for growth that is observed macroscopically as growth on the plate surface or cloudiness in a liquid medium. Important because this is where cells have a chance to duplicate. Isolation Separate individual microbes and achieve isolated colonies Inspection Colonies/broth observed macroscopically for growth characteristics (Color, texture, size) for analysis. Identification Determine the type of microbe. Inoculum Sample. Liquefiable growth media Changes physical properties depend on temp (Agar, Gelatin.) Nonliquefiable media Does not melt (Potato slices.) Agar Growth medium that is flexible, holds nutrients and moisture. Solid at room temperature, not readily digested by organisms. Synthetic/defined growth media All chemicals known. Complex growth media Exact chemical makeup unknown. General purpose growth media Broad spectrum, usually nonsynthetic/complex, no specific growth requirements (nutrient agar or TSA). Grows a bunch of things at once. Just put a bunch on and see what grows. Enriched growth media Complex medium with added special nutrients (vitamins, serum), growth of fastidious organisms. Example: Blood agar. Selective growth media One or more agents that inhibit growth of certain organisms from a mixed sample. Kills one type and selects a different one. Differential growth media Allow for the growth of different microbes but permits ways of telling them apart. Doesn't kill one type. Fastidious organisms Organisms that require complex nutrients and special growth factors. Colony Mounds of cells, consists of one species. Pure culture Only one known species/type of microbe identified. Mixed culture Two or more easily identified species of microbes- the different types SHOULD be there. Contaminated culture Once pure/mixed culture with undesired organisms (CONTAMINANTS) added that ruins experiment. Magnification The ability of a microscope lens to make the image of an object to appear enlarged. Resolution Resolving power, the ability of a microscope lens to distinguish between two separate entities that sit near one another, ability to show detail. Virtual image Image observed by the eye. Formed by ocular lens. Real image Formed by objective lens, closest to the specimen. Total magnification Power of objective lens X power of ocular lens. Mount Specimen placed on glass slide. Smear Dead or fixed preps. Why are studying microbes a challenge for scientists? Microbes hard to see without help, Can have contamination from other undesirable organisms, Microbes found in complex associations so need to separate and identify different organisms, Need to grow organisms in artificial conditions. What are the 5 I's of culturing microbes? Inoculation, Incubation, Isolation, Isolation, Inspection, and Identification. What are examples of instruments used for inoculation? Loop, needles, pipettes, swabs. 4 / 12 Only 1% of all microorganisms are studied in the lab. Why do you Some microbes are nonculturable meaning we can't supply them think this is the case? with the proper growth medium. What are the advantages of the use of agar as the hardening agent in growth medium as compared to gelatin? Agar is solid at room temperature and not digestible by organisms. Also, agar is flexible and holds moisture and nutrients. Agar is what type of macromolecule and is made from what organism? Carbohydrate What are the differences between synthetic and complex media? We know all of the chemicals of synthetic media but complex media has one or more unknown chemicals. If blood or milk is added to a medium, is it complex or synthetic? Complex. Liquefiable or reversible solid media example Agar, Gelatin. Nonliquefiable media example Potato slices. General Purpose Medium Nutrient agar/ Trypticase soy agar (TSA). Complex media example Nutrient agar/blood agar/ EMB/ MacConkey agar. Enriched media example Blood agar. Selective media example EMB/MacConkey agar/ Sabourauds/Salmonella Shigella. Differential media example Hektoen/EMB/ Blood Agar/Bird Seed. examples of growth media that have multiple functions MacConkey and Blood Agar and Mannitol Salt Agar. Name the agents that are used to select for microbes Antimicrobial drugs and acid. Why are pH indicators used to differentiate microbes? pH indicators to indicate presence of acid/base (Neutral red, bromothymol blue). MacConkey: Neutral red, yellow neutral, pink/red acid. E. coli: Acid when use lactose (red/pink). Salmonella: None. What are the different methods of microbe isolation? Streak plate, pour plate and spread plate methods. Which lens of a compound microscope is used to form the virtual image? Ocular lens. Which lens is used to form the Real image? Objective lens. Why does an oil immersion lens require oil for better resolution? Increasing the efficiency of the lens to gather light. Keeps light from bending away from lens. What factors affect the resolution of a microscope? Wavelength How can the wavelength of a light microscope be shorten to improve resolution? Decrease wavelength= better resolution. Lower resolution of light microscope using the blue-green filter. Why are electron microscopes "better" microscopes than light microscopes? Better resolution, better magnification. Shows fine details of cell and virus structure. What are the basic differences between light and electron micro- Dead specimens and magnet lenses. Stained with metal for conscopes? trast. What are the different mounts that can be prepared? living or dead preps. Basic dyes (cationic) + charged chromophore. Attract - charged cell parts. Stain most bacteria (Positive Stain). Example: Methylene blue, crystal violet, fuchsin, safranin, malachite green. Acidic dyes (anionic) - charged chromophore. Attract + charged cell parts, stain eukaryotes, bacteria repel so stain remains outside (negative stain). Example: Eosin (red), India ink, Nigrosin. Positive staining Dye sticks to cells to color, Background not stained. Uses basic dyes: Crystal violet, methylene blue. Subtypes: Simple, Differential, Special stains. Negative staining Dye settles outside cells, Background stained dark. Acidic dyes: India ink, Nigrosin. Subtypes: Capsule, Endospore stains. Which type of stain (basic acidic) is better for staining bacteria and Basic because bacteria contain a lot of acid so they repel the acidic why? dye and the acidic stain would remain outside. Simple stain a single stain. Ex- Malachite Green, crystal violet, safarrin. 5 / 12 Differential stain Complex, two different colored dyes to tell two types of cells apart (Primary stain then Counter Stain used once primary stain is removed). Ex- Acid Fast, Gram stain, Endospore stain. Which stain can be used to view Mycobacterium? Acid Fast Stain. Gram Staining Procedure 1. Crystal violet is the primary stain of the Gram stain. All cells become purple. 2. Alcohol, the decolorizer, is added. During a Gram stain, after this reagent is added to gram-positive organisms, they appear purple. During a Gram stain, after this reagent is added to gram-negative organisms, they appear as clear. 3. Iodine, the mordant of the Gram stain, is added. All cells are purple. 4. Safranin is the counterstain of the Gram stain. After safranin is added to gram-positive organisms, they appear purple and the gram negative organisms appear pink. Gram stain is used to differentiate between cells based on what structure? Differences in cell walls What is the primary stain of the acid-fast stain? Carbol fuchsin. What is the Counterstain of the acid fast stain? Brilliant Green. What is the Decolorizer of the acid fast stain? Acid alcohol. Chemotaxis Organisms move toward or away from a chemical stimulus. Axial filaments Periplasmic, internal flagella, enclosed between cell wall and cell membrane of spirochetes (Borrelia). Produce cellular motility by contracting and imparting twisting or flexing motion. Fimbriae Fine, proteinaceous, hairlike bristles from the cell surface. Function in adhesion to other cells and surfaces. Slime layer Loosely organized and attached layer of the Glycocalyx. A loose shield that evidently protects bacteria from dehydration and loss of nutrients. Capsule Highly organized and tightly attached layer of the Glycocalyx. Composed of repeating polysaccharide units, protein or both. Biofilm Microcolonies of microbes encased in EPS matrix & separated from others by water channels. Consists of exopolysaccharides (EPS) and microbes. EPS Primary matrix material made of polysaccharides. Peptidoglycan Unique macromolecule composed of a repeating framework of long glycan chains cross-linked by short peptide fragments. Primary part of the cell walls. Acid polysaccharides Functions in cell wall maintenance, enlargement during cell division, more permeable: move cations across the cell envelope, stimulate a specific immune response. Teichoic acid Acid polysaccharide attached to peptidoglycan. Lipopolysaccharides Endotoxin that may become toxic when released during infections. May function as receptors and blocking immune response. Nucleoid Dense area containing tightly coiled DNA around a protein. Plasmid Small circular, double-stranded DNA. Free or integrated into the chromosome, duplicated and passed on to offspring. Not essential to bacterial growth and metabolism. May encode antibiotic resistance, tolerance to toxic metals, enzymes and toxins. Used in genetic engineering: Readily manipulated and transferred from cell to cell. Magnetosomes Iron oxide. Endospore Not reproductive, different form when exposed to adverse environmental conditions; high resistance and very long-term survival. Vegetative cell Metabolically active & growing phase of a bacterial cell. 6 / 12 Sporangium Once this stimulus has been received by the vegetative cell, it converts to a committed sporulating cell called a sporangium. Coccus Spherical. Bacillus Rod. Spirillum Helical, comma, twisted rod. Bergey's Manual Five volume resource covering all known prokaryotes. Classification based on genetic information. Phylogenic. 2 domains: Archaea and Bacteria and 5 major subgroups with 25 different phyla) Firmicutes Mainly Gram-positive with low G + C content (Clostridium, Bacillus, Staphylococcus, Streptococcus) Proteobacteria Gram-negative cell walls (Rickettsias, enterics, Helicobacter). Actinobacteria Gram-positive with high G + C content (Mycobacterium, Micrococcus). Heterocyst Fix Nitrogen gas (important in forming an oxygen atom). Bacteriochlorophyll Not give off oxygen. Anaerobic, in sulfur springs, swamps. Use sulfur compounds metabolically. Gliding motility Rotation of filaments under the OM (no flagella). Extremophile Live in the most extreme habitats in nature (heat, salt, acid pH, pressure & atmosphere). Basic shape: Spherical,cubical, cylindrical. Internal content: CyWhat are the general characteristics of cells that were discussed toplasm, surrounded by a membrane. Genetic material: DNA in lecture? chromosome(s). Protein synthesis: Ribosomes. Perform complex chemical reactions (METABOLISM). What are the two types of appendages found on the outside of bacterial cells? Locomotor and Glycocalyx Atrichous No flagellar attachment Monotrichous Single flagellum. Lophotrichous Small bunches arising from one end of cell. Amphitrichous Flagella at both ends of cell. Peritrichous Flagella dispersed over surface of cell; slowest. Pili Rigid tubular structure made of pilin protein. Mostly in Gram negative cells, some Gram +. Function to join bacterial cells for partial DNA transfer called conjugation. Fimbriae Fine, proteinaceous, hairlike bristles from the cell surface.Function in adhesion to other cells and surfaces. What are the two types of glycocalyx? Slime layer-Loosely organized & attached and Capsule layer which is Highly organized tightly attached. Glycocalyx A network of fibers made of polysaccharides that come in direct contact with environment. Has a slime layer, capsule and extracellular matrix. Functions: Adherence, biofilms, protection, signal reception. Below the glycocalyx: In fungi and algae- thick rigid cell wall. In protozoa and all animal cells- no cell wall, only a membrane. Septated Cytoplasm & nuclei of hyphae divided by cross walls. Microcolonies of microbes encased in EPS matrix & separated from others by water channels. Consists of exopolysaccharides What is the function of biofilms and name an example of where to (EPS) and microbes. EPS: Primary matrix material made of polyfind these structures saccharides. Benefits: Protect against antibodies and antibiotics; phagocytosis. Important for infections: Dental plaque, in dwelling devices, UTIs. Maintains cell integrity-Determines cell shape prevents lysis (bursting) or collapsing due to changing osmotic pressures. What is the importance of the cell envelope in bacteria? 7 / 12 What two components make up the cell envelope? Peptidoglycan and Acid polysaccharides. Gram-positive bacteria Thick cell wall composed primarily of peptidoglycan and cell membrane. One layer. Gram-negative bacteria Outer cell membrane, thin peptidoglycan layer, and cell membrane. Two layers. Less peptidoglycan than Gram positive. What color are Gram-positive bacteria? Purple. Gram-negative bacteria? Red. What organisms are stained with the acid-fast stain? Mycobacterium. What the two cell types involved in the endospore life cycle? Endospore and Vegetative Cell. Which cell is dormant? Endospore. Which endospore cell is viable or active? Vegetative Cell. What is the advantage if a bacterium being able to form endospores? Hardiest of all life forms: 250 million yrs. Resistant to ordinary cleaning methods & boiling. Withstands extremes: Heat, drying, freezing, radiation and chemicals. Resistance linked to a thick coat that has high levels of calcium and dipicolinic acid. Name two examples of organisms that can make endospores (Genus name) Clostridium and Bacillus. Bergey's manual classifies bacteria based on what? Genetic information: Phylogenetic. Be familiar with the phyla of the domain Bacteria Spirochaetes, Deinococcus-Thermus, Aquificae, Cyanobacteria, Chloroflexi, Thermotogae, Proteobacteria, Firmicutes Know examples of bacteria that are photosynthetic. Cyanobacteria (blue-green algae); Gliding or fruiting bacteria and green and purple sulfur. What structures are found in cyanobacteria and not in many other bacteria? Chlorophyll, heterocysts. What important process do cyanobacteria perform? Fix nitrogen gas. Name examples of cyanobacteria discussed in class. Anabaena, Arthrospira. What are the main differences between cyanobacteria and green Green and Purple sulfur also perform photosynthesis but they use & purple sulfur bacteria? bacteriochlorophyll and are anaerobic. Example: Chlorobium. Name one example of myxobacteria Myxococcus. Fruiting bodies are produced when myxobacteria are starving. Know examples of intracellular obligate parasites that are pathogens Rickettsia and Chlamydia. How are archaea different from other bacteria? Unique genetic sequences in their rRNA; Unique membrane lipids & cell wall construction; no peptidoglycan. No spores. Asexual reproduction: Binary fission, fragment, budding. Endosymbiosis Eukaryotes evolved from larger prokaryotes that engulfed smaller prokaryotes. Cristae Outer membrane & inner membrane with folds. Hold the enzymes & electron carriers of aerobic respiration. Matrix Space inside inner membrane. Thylakoid Inner membrane folded into sacs. Hyphae Multicellular, Basic units, A slender filaments of cytoplasm & nuclei enclosed by a cell wall (Molds or long filamentous fungi). Yeast Single cell, round ovoid shape, asexual reproduction by budding. Saprobe Harmless, live off of dead plants and animals; waste. Mycoses fungal infections. Mycelium Interwoven mass of hyphae. Sporangiospores 8 / 12 Asexual Spores. Successive cleavages in a sac-like head (Sporangium) attached to a stalk (Sporangiophore). Release thru rupture. Conidia Asexual Spores. Common. Free spores not enclosed in a sac. Pinching off of special hyphae or segmentation of vegetative hyphae. Zygospores Sexual spore. Two mycelia fuse to form zygote/zygospore. Zygospore germinate and form mycelia then sporangium. Ascospores Spores in sac (Ascus), Ascospore germinate then form conidia. Ascus Spores in a sac. Basidiospores Spores in club shaped cell (Basidium). Basidiospore germinate to form conidia. Basidium Spores in a club shaped cell. Heterotroph Not make own food: Feed by engulfing other microbes (algae, bacteria), scavenge dead organisms and organic matter, food to grooves into gullet for packaging food in vacuoles. Autotroph Make own food by photosynthesis. Dinoflagellates Red tide. Unicellular, Ceratium, cellulose cell walls, chlorophyll (red tides) give off toxins that cause food poisoning with neurological symptoms. Diatoms (Golden brown algae): Unicellular, silicate cell walls, chlorophyll, plankton. Spirogyra Pond scum. Pseudopod How protozoa move. Trophozoite Motile feeding stage of a protozoan life cycle; all. Cyst Dormant resting stage of a protozoan life cycle when conditions are unfavorable; some. Conjugation Sexual reproduction that occurs in some protozoa. Transverse fission Asexual reproduction in protozoa. Sporozoite Type of cyst. Basic parts of a eukaryotic cell Organelles- structures that specialize function- compartmentalize. Flagella, cilia, glycocalyx, capsule, cell membrane, nucleus, ER, Golgi. What are the basic differences between flagella and cilia? Flagella: Cylinder with regularly spaced microtubules in a 9+2 arrangement (9 pairs around one pair). More complex and 10X thicker than prokaryotic flagella. Function: Motility. Cilia: Similar 9+2 microtubular arrangement. Shorter & more numerous. Only on certain protozoa & certain animal cells. Function: Motility- feeding and filtering Which microbes have cell walls? Fungi and Algae. What molecules are in their cell walls (chitin etc)? Fungi- chitin. Alage- cellulose. What is the difference between eukaryotic and prokaryotic ribosomes? Eukaryotes are Larger. Know examples of vacuoles Cyst and contractile vacuole. If a cell does not have chloroplasts what function can it not do? Photosynthesis. Why are mitochondria and chloroplasts thought to be ancient bacteria? They Divide independently of cell, Contain DNA & prokaryotic 70S ribosomes, double membrane. Fungi 2 groups: Macroscopic and microscopic fungi. Exist as either vegetative cells or spores. Some exist in either form. Most fungi grow in loose associations (colonies). Either yeast colonies or filamentous fungi. All fungi are heterotrophic. Most fungi are harm9 / 12 less saprobes (decomposers) but some are parasites. Extremely widespread. Grow best between 20 and 40 degrees. What cholesterol-like compound is found in fungal cell membranes to aid in stability? Ergosterol What are the two vegetative forms of fungi? Yeast form and hyphae. How can hyphae be classified? Based on presence of division between cells or on function. Nonseptated Hyphae not divided, multinucleated. Aerial vs. vegetative? Aerial produce spores for reproduction. Vegetative absorb nutrients. What are the asexual ways fungi can reproduce? Mitotic, fragmentation, budding. Sexual ways fungi can reproduce? Meiosis. What are the basic types of asexual spores made by fungi? More common? Conidia and sporangiospores. Conidia more common. With sporangiospores, there are successive cleavages in a sac What are the fundamental differences? between conidia and spo- like head but conidia don't have any sacs; they are formed by rangiospores? pinching. Examples of Conidida- Chlamydospores, Blastospores, Phialospores, Microconidium, macroconidium, Porospore. Which type of asexual spore is located in a sac-like head? Sporangiospore. What are the three sexual spores of fungi? Zygospore, Ascospore, Basidiospore. Using your basic knowledge from lab and lecture how would you know if a sample on an agar plate is a potential fungus? Large and fuzzy. What type of medium could you use to help isolate fungi? Saboroud or PDA How are fungi beneficial? Decomposer, produce antibiotics and hormones, make food. How are fungi Harmful? Allergies, crop destruction, mold, release enzymes to break down material then digest, mycoses- fungal infections. Algae nutrition- autotroph cell wall- cellulose reproduction, sexual (conjugation) and asexual, uses of algae cosmetics, food and medical products. Basis of food chain. What causes red tide? Dinoflagellates. Be familiar with examples of pathogenic algae. Pfiesteria, Dinoflagellates. What pigment do algae possess? Chlorophyll Protozoa nutrition- Heterotroph. cell wall- no cell wall. reproduction- Complex, sexual and asexual. Name three cellular structures protozoa use for locomotion. Flagella, cilia, pseudopods. Mastigophora Motility: Flagellar, some flagellar & amoeboid. Single nucleus. Asexual: Binary Fission, Some sexual reproduction. Cysts & trophozoite. Parasites, free-living. Examples: Euglena, Trypanosoma, Leishmania, Trichomonas, Giardia. Sarcodina Motility: Pseudopodia. Single nucleus. Asexual reproduction (Binary fission). Cysts & trophozoites. Parasites, most freeliving. Example: Entamoeba, Radiolaria(Silicon), Foraminifera. Apicomplexa (Sporozoa) Motility : Only male gametes. Single nucleus. Asexual & sexual reproduction, complex. Most cysts (oocysts), sporozoites, trophozoites. Parasites . Examples: Plasmodium, Toxoplasma, Cryptosporidium. Ciliophora Ciliates Common in water. Cilia on trophozoites. Macronuclei & micronuclei. Asexual reproduction (transverse fission). Most cysts, trophozoites. Most free-living, harmless. Examples: Balantidium coli, paramecium, tetrahymena. Trypanosomes- T. Brucei (African sleeping sickness) T Cruzi- Chaga's disease. 10 / 12 Be familiar with the examples of parasitic protozoa and the infections they cause Leishmania- Sandfly skin. Trichomonas- STDs Giardia- Intestines Yeast, algae, protozoa and molds are all Eukaryotes. Robert Koch Clearly linked a microscopic organism with a specific disease.Established Koch's postulates. Louis Pasteur Invented pasteurization and completed some of the first studies showing that human disease can rise from infection. Invented the germ theory of disease. Domain Giant, all inclusive category based on a unique cell type (Eukarya, Bacteria, Archaea) 5 I's of Microbal investigation. Inoculation, Incubation, Isolation, Inspection, Identification. Electron: Much higher magnification and resolution ability. It scans and magnifies external surface of specimen; produces striking 3D image. Image Scanning electron microscope versus bright field light microscope Light: Common multipurpose microscope for live and preserved stained specimens, specimen will be dark, field is white; provides fair detail. Lactic Acid bacteria Produce Dairy products (yogurt/cheese) by the lactic acid fermentation of milk. Yeast makes Beer, wine, bread. Cheese fermented by Lactic acid bacteria Leavening of bread Caused by alcohol fermentation of yeast. Use starch converted sugars in dough to make CO2 and ethanol. Different microbes give different flavors. Alcohol production Caused by alcohol fermentation of yeast. Converted starch in barley or grapes into sugars. Ferment to CO2 and ethanol. What makes blue cheese blue? Fungi- penicillium mold. Medium Food source. Examples of nutrient medium Broth/agar plate. Blood. Living organisms. Nutrient media categorized by... Physical state/consistency. Chemical composition. Functional type. Solid/ firm surface. Agar plate- needed to isolate individual colonies. Agents used to inhibit growth on a selective media Bile salts, dyes, antimicrobal drugs and acid. Streak plate method Most common, small droplet of culture spread over medium surface to think out/ dilute. Pour plate method Loop dilution, inoculate into tubes of cooled liquid agar to dilute cells. Spread plate method Small volume using hockey stick Living preps Wet mounts: Drop culture on slide, cover, damage cells and drying (negative stain). Hanging drop mounts: Depression, sealant. Advantages: See true size and shape, motility Smears Dead/ fixed preps. Need to kill the stain on a bright field microscope to provide contrast but it also kills the cells which changes cell structure and prepares a smears. Purpose of smear: To kill cells, adhere specimen, coagulate proteins to aid in keeping stain. Spread thin film of cells in liquid on slide, air dry, heat fix. Chromophore Ion form of the dye and attracts cell parts with the opposite charge. Cell wall Functions: Rigidity and provides structural support and shape. Fungi have a thick inner layer of polysaccharide fibers (chitin) and 11 / 12 a think layer of mixed glycans. Algae cell walls vary in chemical composition- most often have cellulose. Cell membrane Bilayer of phospholipids and proteins. Selective permeability barrier in transport. Eukaryotic cells: membrane bound organelles (account for 60-80% of volume). Nucleus Compact sphere, most prominent organelle. Nuclear envelope: 2 parallel membranes separated by a narrow space, perforated with pores. Nucleoplasm: Chromosomes, mitosis. Nucleolus: Dark area for rRNA synthesis and ribosome assembly. Function: Genome storage, ribosome made. Smooth Endoplasmic Reticulum Functions: nutrient processing. Storage and production of lipids and phospholipids etc. Golgi Apparatus Stack of flattened sacs called cisternae. Associated with ER. Function: Modify and mature proteins from the ER (vesicles). Condensing vesicles transport proteins to organelles or secretory proteins to the outside. Lysosomes Vesicles containing enzymes that originate from Golgi. Function: Involved in intracellular digestion of food particles, protect against invading microbes. Mitochondria Outer membrane and inner membrane with folds (cristae). Matrix: Space inside IM. Cristae hold the enzymes and electron carriers of aerobic respiration. Dna and ribosomes. Function: Energy production. Chloroplast In algae and plant cells. Outer membrane covers inner membrane folded into sacs (thylakoids) stacked into granum. Larger than mitochondria. Has photosynthetic pigments. Function: Convert the energy of sunlight into chemical energy through photosynthesis. Primary producers of organic nutrients for other organisms. Cytoskeleton Flexible framework of proteins, microfilaments and microtubules form network throughout cytoplasm. Function: Involved in movement of cytoplasm, amoeboid movement, transport and structural support. Why is heat fixation important? Because it preserves various cellular components in a natural state with minimal distortion. 12 / 12