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Microbiology Exam 1 (Chapters 1, 3-5)
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Microbiology - correct answer::Specialized area of biology that deals with organisms ordinarily too small to be seen without magnification. Microorganisms - correct answer::A living thing ordinarily too small to be seen without magnification. Classification - correct answer::Orderly arrangement of organisms into groups. Nomenclature - correct answer::System of assigning names. Binomial nomenclature - correct answer::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 - correct answer::Viruses. Exist without a cellular structure. Cellular organisms - correct answer::Prokaryotes and Eukaryotes. Prokaryotes - correct answer::Organisms whose genetic material is not enclosed in membrane and lack specific organelles including a nucleus (bacteria). Eukaryotes - correct answer::Organisms whose genetic material is enclosed in nucleus (fungi, protozoa, algae). Prokaryotes versus Eukaryotes - correct answer::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 - correct answer::The way bacteria reproduce. Splitting of a parent cell into two equal parts. Mycology - correct answer::The study of fungi. Phycology - correct answer::The study of simple photosynthetic eukaryotes (algae) ranging from single celled forms to large seaweeds. Pathogen - correct answer::Disease causing agents. Genetic engineering - correct answer::Manipulates the genetics of microbes, plants, and animals for the purpose of creating new products and genetically modified organisms. Recombinant DNA - correct answer::Switch DNA from one organism to another to design new organisms. Lactic acid bacteria - correct answer::Dairy products, yogurt and cheese. Curds - correct answer::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 - correct answer::Liquid part of day old milk, mostly water. Rennin - correct answer::Turn caseinogens to casein. Curdling - correct answer::Products cause milk to separate into curds (the milk solids, fats, proteins, etc. Scientific method - correct answer::Approach taken by scientists to explain a certain natural phenomenon.
Antibiotics - correct answer::Chemical substance made by microbes. General sizes of macroscopic organisms? - correct answer::1 mm Size of Microscopic organisms? - correct answer::1 um to 100 um Size of Viruses? - correct answer::10 nm to 100 nm What are the 3 domains used in the Woese-Fox system of classification? - correct answer::Bacteria, Archaea, Eukarya. Which domain are fungi members of? - correct answer::Eukarya Which domain are Protozoa? - correct answer::Eukarya Which domain are Algae? - correct answer::Eukarya Which domain are E. coli? - correct answer::Bacteria Which domain are Viruses? - correct answer::Neither Viruses - correct answer::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 - correct answer::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 - correct answer::Unicellular, some are multicellular. Reproduce asexually and sexually. Nutrition by photosynthesis. Cell wall made of cellulose. Fungi - correct answer::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 - correct answer::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 - correct answer::Pseudopods, flagella, cilia. Be familiar with the ways that microorganisms are beneficial - correct answer::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. - correct answer::Found everywhere, part of the ecosystem (make greenhouse gasses, soil formation, mineral extraction), Nutrient recycling (CO and Nitrogen fixation). Decomposition. Interactions with other organisms- pathogens or beneficial. Mycology - correct answer::Study of fungi. Protozoology - correct answer::Study of protozoa. Virology - correct answer::Study of viruses. Phycology - correct answer::Study of simple photosynthetic eukaryotes. Morphology - correct answer::Study of detailed structure of microorganisms. Physiology - correct answer::Study of Microbial function.
Redi - correct answer::No flies from meat. Pasteur - correct answer::S-neck flask and aseptic technique. Vaccine for cholera and rabies. Schwann & Schleiden - correct answer::All living things are made of cells. Virchow - correct answer::Living cells come from preexisting cells. Lister - correct answer::Use carbolic acid sprayer (phenol) to sterilize surgical wounds and instruments to reduce infection. Semmelweis - correct answer::Hand washing during child birth by doctors. Jenner - correct answer::Vaccine for smallpox. Ehrlich - correct answer::Coined term "chemotherapy." Used the first synthetic chemo that did not damage tissue: Magic bullet. Flemming - correct answer::Penicillin from mold. Venter & Smith - correct answer::Complete sequence of bacterial genome. What are the three theories of how life emerged discussed in lecture? - correct answer::Cell theory, biogenesis, spontaneous generation. What were the major accomplishments of the Golden Age of Microbiology? - correct answer::Fermentation Pasteurization, Germ Theory, Vaccination. Why does milk spoil even if it is pasteurized? - correct answer::Some spoilage organisms stay.
Name two foods that are pasteurized besides milk - correct answer::Eggs, Honey. What are the two types of chemotherapy? - correct answer::Synthetic drugs and antibiotics. Sterile - correct answer::Complete absence of viable microbes. Aseptic - correct answer::Prevent infection. Inoculation - correct answer::Cultivating (CULTURING) microorganisms by introducing a sample (INOCULUM) into a container of nutrient medium. Culture - correct answer::Observable growth that appears in or on the medium (cloudiness, colony) Incubation - correct answer::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 - correct answer::Separate individual microbes and achieve isolated colonies Inspection - correct answer::Colonies/broth observed macroscopically for growth characteristics (Color, texture, size) for analysis. Identification - correct answer::Determine the type of microbe. Inoculum - correct answer::Sample. Liquefiable growth media - correct answer::Changes physical properties depend on temp (Agar, Gelatin.) Nonliquefiable media - correct answer::Does not melt (Potato slices.)
Magnification - correct answer::The ability of a microscope lens to make the image of an object to appear enlarged. Resolution - correct answer::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 - correct answer::Image observed by the eye. Formed by ocular lens. Real image - correct answer::Formed by objective lens, closest to the specimen. Total magnification - correct answer::Power of objective lens X power of ocular lens. Mount - correct answer::Specimen placed on glass slide. Smear - correct answer::Dead or fixed preps. Why are studying microbes a challenge for scientists? - correct answer::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? - correct answer::Inoculation, Incubation, Isolation, Isolation, Inspection, and Identification. What are examples of instruments used for inoculation? - correct answer::Loop, needles, pipettes, swabs. Only 1% of all microorganisms are studied in the lab. Why do you think this is the case? - correct answer::Some microbes are nonculturable meaning we can't supply them 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? - correct answer::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? - correct answer::Carbohydrate What are the differences between synthetic and complex media? - correct answer::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? - correct answer::Complex. Liquefiable or reversible solid media example - correct answer::Agar, Gelatin. Nonliquefiable media example - correct answer::Potato slices. General Purpose Medium - correct answer::Nutrient agar/ Trypticase soy agar (TSA). Complex media example - correct answer::Nutrient agar/blood agar/ EMB/ MacConkey agar. Enriched media example - correct answer::Blood agar. Selective media example - correct answer::EMB/MacConkey agar/ Sabourauds/Salmonella Shigella. Differential media example - correct answer::Hektoen/EMB/ Blood Agar/Bird Seed. examples of growth media that have multiple functions - correct answer::MacConkey and Blood Agar and Mannitol Salt Agar. Name the agents that are used to select for microbes - correct answer::Antimicrobial drugs and acid.
Acidic dyes (anionic) - correct answer::- charged chromophore. Attract + charged cell parts, stain eukaryotes, bacteria repel so stain remains outside (negative stain). Example: Eosin (red), India ink, Nigrosin. Positive staining - correct answer::Dye sticks to cells to color, Background not stained. Uses basic dyes: Crystal violet, methylene blue. Subtypes: Simple, Differential, Special stains. Negative staining - correct answer::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 why? - correct answer::Basic because bacteria contain a lot of acid so they repel the acidic dye and the acidic stain would remain outside. Simple stain - correct answer::a single stain. Ex- Malachite Green, crystal violet, safarrin. Differential stain - correct answer::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? - correct answer::Acid Fast Stain. Gram Staining Procedure - correct answer::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? - correct answer::Differences in cell walls What is the primary stain of the acid-fast stain? - correct answer::Carbol fuchsin.
What is the Counterstain of the acid fast stain? - correct answer::Brilliant Green. What is the Decolorizer of the acid fast stain? - correct answer::Acid alcohol. Chemotaxis - correct answer::Organisms move toward or away from a chemical stimulus. Axial filaments - correct answer::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 - correct answer::Fine, proteinaceous, hairlike bristles from the cell surface. Function in adhesion to other cells and surfaces. Slime layer - correct answer::Loosely organized and attached layer of the Glycocalyx. A loose shield that evidently protects bacteria from dehydration and loss of nutrients. Capsule - correct answer::Highly organized and tightly attached layer of the Glycocalyx. Composed of repeating polysaccharide units, protein or both. Biofilm - correct answer::Microcolonies of microbes encased in EPS matrix & separated from others by water channels. Consists of exopolysaccharides (EPS) and microbes. EPS - correct answer::Primary matrix material made of polysaccharides. Peptidoglycan - correct answer::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 - correct answer::Functions in cell wall maintenance, enlargement during cell division, more permeable: move cations across the cell envelope, stimulate a specific immune response. Teichoic acid - correct answer::Acid polysaccharide attached to peptidoglycan.
Proteobacteria - correct answer::Gram-negative cell walls (Rickettsias, enterics, Helicobacter). Actinobacteria - correct answer::Gram-positive with high G + C content (Mycobacterium, Micrococcus). Heterocyst - correct answer::Fix Nitrogen gas (important in forming an oxygen atom). Bacteriochlorophyll - correct answer::Not give off oxygen. Anaerobic, in sulfur springs, swamps. Use sulfur compounds metabolically. Gliding motility - correct answer::Rotation of filaments under the OM (no flagella). Extremophile - correct answer::Live in the most extreme habitats in nature (heat, salt, acid pH, pressure & atmosphere). What are the general characteristics of cells that were discussed in lecture? - correct answer::Basic shape: Spherical,cubical, cylindrical. Internal content: Cytoplasm, surrounded by a membrane. Genetic material: DNA chromosome(s). Protein synthesis: Ribosomes. Perform complex chemical reactions (METABOLISM). What are the two types of appendages found on the outside of bacterial cells? - correct answer::Locomotor and Glycocalyx Atrichous - correct answer::No flagellar attachment Monotrichous - correct answer::Single flagellum. Lophotrichous - correct answer::Small bunches arising from one end of cell. Amphitrichous - correct answer::Flagella at both ends of cell.
Peritrichous - correct answer::Flagella dispersed over surface of cell; slowest. Pili - correct answer::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 - correct answer::Fine, proteinaceous, hairlike bristles from the cell surface.Function in adhesion to other cells and surfaces. What are the two types of glycocalyx? - correct answer::Slime layer-Loosely organized & attached and Capsule layer which is Highly organized tightly attached. Glycocalyx - correct answer::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 - correct answer::Cytoplasm & nuclei of hyphae divided by cross walls. What is the function of biofilms and name an example of where to find these structures - correct answer::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. Benefits: Protect against antibodies and antibiotics; phagocytosis. Important for infections: Dental plaque, in dwelling devices, UTIs. What is the importance of the cell envelope in bacteria? - correct answer::Maintains cell integrity- Determines cell shape prevents lysis (bursting) or collapsing due to changing osmotic pressures. What two components make up the cell envelope? - correct answer::Peptidoglycan and Acid polysaccharides. Gram-positive bacteria - correct answer::Thick cell wall composed primarily of peptidoglycan and cell membrane. One layer.
What structures are found in cyanobacteria and not in many other bacteria? - correct answer::Chlorophyll, heterocysts. What important process do cyanobacteria perform? - correct answer::Fix nitrogen gas. Name examples of cyanobacteria discussed in class. - correct answer::Anabaena, Arthrospira. What are the main differences between cyanobacteria and green & purple sulfur bacteria? - correct answer::Green and Purple sulfur also perform photosynthesis but they use bacteriochlorophyll and are anaerobic. Example: Chlorobium. Name one example of myxobacteria - correct answer::Myxococcus. Fruiting bodies are produced when myxobacteria are - correct answer::starving. Know examples of intracellular obligate parasites that are pathogens - correct answer::Rickettsia and Chlamydia. How are archaea different from other bacteria? - correct answer::Unique genetic sequences in their rRNA; Unique membrane lipids & cell wall construction; no peptidoglycan. No spores. Asexual reproduction: Binary fission, fragment, budding. Endosymbiosis - correct answer::Eukaryotes evolved from larger prokaryotes that engulfed smaller prokaryotes. Cristae - correct answer::Outer membrane & inner membrane with folds. Hold the enzymes & electron carriers of aerobic respiration. Matrix - correct answer::Space inside inner membrane. Thylakoid - correct answer::Inner membrane folded into sacs.
Hyphae - correct answer::Multicellular, Basic units, A slender filaments of cytoplasm & nuclei enclosed by a cell wall (Molds or long filamentous fungi). Yeast - correct answer::Single cell, round ovoid shape, asexual reproduction by budding. Saprobe - correct answer::Harmless, live off of dead plants and animals; waste. Mycoses - correct answer::fungal infections. Mycelium - correct answer::Interwoven mass of hyphae. Sporangiospores - correct answer::Asexual Spores. Successive cleavages in a sac-like head (Sporangium) attached to a stalk (Sporangiophore). Release thru rupture. Conidia - correct answer::Asexual Spores. Common. Free spores not enclosed in a sac. Pinching off of special hyphae or segmentation of vegetative hyphae. Zygospores - correct answer::Sexual spore. Two mycelia fuse to form zygote/zygospore. Zygospore germinate and form mycelia then sporangium. Ascospores - correct answer::Spores in sac (Ascus), Ascospore germinate then form conidia. Ascus - correct answer::Spores in a sac. Basidiospores - correct answer::Spores in club shaped cell (Basidium). Basidiospore germinate to form conidia. Basidium - correct answer::Spores in a club shaped cell. Heterotroph - correct answer::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.
