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69 Cards in this Set
- Front
- Back
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what is an endospore?
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dormant structure within a cell that are more resistant to environment factors such as UV light, heat, chemicals, and dehydration
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true or false: gram - bacteria can form endospores
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false. only gram + bacteria can form endospores
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what are the 2 primary genera which form endospores?
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Bacillus and Clostridium
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what organism of the genera Bacillus is responsible for anthrax?
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Bacillus anthracis
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what organism of the genera Clostridium is responsible for botulism and tetanus?
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botulism-Clostridium botulinum
tetanus-Clostridium tetani |
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true or false: metabolic activities do not take place inside endospores
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true. endospores are a survival mechanism and are not needed for reproduction of the cell. one spore can only form one new cell
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what are the steps of sporulation and germination?
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DNA replicates and spore septum forms
engulfment by mother cell, forespore begins to form spore coat develops lysis of mother cell free endospore returns to vegetative cell once conditions are favorable again |
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what is another name for the mother cell when talking about endospores?
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sporangium
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define germination
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occurs when optimal growth conditions persist; one endospore will germinate to form one vegetative cell
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define sporulation
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begins when nutrients or water become depleted or other conditions such as temperature, chemical contamination, ph, etc. become unfavorable for the cell. at the end of the proces lytic enzymes destroy the mother cell, or sporangium and the mature spore is released.
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define vegetative cell
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cells that grow and divide under optimal conditions; do not contain endospores
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define sporangium
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mother cells; cells that are in the process of sporulation
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can an endospore be viewed under the microscope using a simple stain?
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yes. if the sporangium remains intact, the endospore will appear as a refractile area (clear area) with the vegetative cell
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discuss the steps of visualizing an endospore using the
Schaeffer-Fulton method |
the spores will be stained using malachite green along with extensive heating to drive the dye into the spore
the vegetative cells and sporangium are counterstained with safranin |
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what is chitin?
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found within the cell wall of the eucaryotic fungi. chitin containing structures stain light brown or blue
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what are the 2 main fungal structures that may be viewed using the lactephenol cotton blue stain?
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Hyphae-threadlike structures
Conidia-fungal reproductive structures at tips of Hyphae |
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what is the stain used to dye fungi?
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lactephenol cotton blue
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VIEW ALL PICTURES FROM SPECIAL STAINING POWERPOINT AND ANYTHING EXTRA IN FOLDER ON BLACKBOARD
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!!!!!!!!!!!!
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What is the scientific name for Black Mold?
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Aspergillus-a filamentous fungi. this genus causes skin infections in burn victims and the fungal lung infection aspergillosis
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what is a capsule stain?
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allows for visualization of glycocalyx capsule surrounding some bacteria. thos capsule is sally composed of polysaccharide, polypeptide, or both
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true or false: organism that have capsules need it as an essential cellular component
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false. it is inherited. capsules are often only produced under specific growth conditions. even though not essential for life, capsules probably help bacteria to survive in nature.
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what are some benefits of a capsule?
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help many pathogenic nad notmal flora bacteria to initially resist phagocytosis by the host's phagocytic cells
in soil and water, capsules help prevent bacteria from being engulfed by protozoans capsules also help many bacter to adhere to surfaces and thus rsist flushing prevent the cell from drying out due to its high volume of water aid in the exclusion of bacterial viruses |
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what is virulence factor?
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anything that contributes to an organism's ability to cause disease
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what stain i sued to stain a capsule?
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india ink
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true or false: capsule dont normally take up acidic or basic stains
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true
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how is a capsule stain conducted?
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the background is stained rather than the organism. the non-stained capsule will appear as a white "halo" surrounding the cell
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what type of stain is india ink?
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acidic. it is negatively charged. the cells also have a negative net charge so this stain will not penetrate the cells but will be repelled by the cells and stain the background
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when viewing a capsule stain under the microscope what would appear as a purple color?
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sometimes the crystal violet can penetrate certain portions of the capsule and these appear as a purple rod in the center of the clear area (capsule)
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when viewing a capsule stain under the scope what would appear as the clear area
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capsule
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when viewing a capsule stain under the scope what would actually be dyed/stained?
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background and sometimes portion of the cell
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what are 2 examples of organism that form capsules?
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Klebsiella pneumoniae
Streptococcus pheumoniae |
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what is flagella?
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threadlike structure attached to bacterial cell walls that allow for bacterial movement
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how big are flagella?
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usually <0.2 um but may be up to 20 um long
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is flagella normally viewable under light microscopy?
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no, however, tannic acid and potassium alum can serve as mordants to increase the diameter of the flagella to allow for light microscope visualization
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what is motility?
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it is an inherited phenotype
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how can you determine motility of an organism?
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by using a semi-solid media with a color indicator, inoculate the tube with an organism using an inoculating needle. inoculate and read results. if stab line appears fuzzy or colored streaks are seen radiating outward from the stab line this is indicative of motility
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what is monotrichous polar and what organism might display this?
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single flagellum at one pole
Vibrio cholerae |
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what is amphitrichous?
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single flagellum at each pole
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what is lophotrichous?
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two or more flagellum at one or both poles of the cell
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what is peritrichous?
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completely surrounded by flagella
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_____ was used to stain the endospores for the Schaeffer-Fulton method and it has a positive charge, so based on the charge it is considered a(an) _____ stain.
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malachite green; basic
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name one benefit of a capsule
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helps bacteria to adhere to surfaces
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of the following flagella arrangement, which would describe an organism that has 2 or more flagella at one or both ends?
a.) amphitrichous b.) peritrichous c.) lophotrichous d.) monotrichous |
c.) lophotrichous
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which stain was used to stain the vegetative cells and sporangium in the endospore staining procedure
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Safranin
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flagella are normally too small to be seen with a light microscope unless a special staining procedure is used that contains a mordant to thicken the flagella
true or false |
true
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true or false: capsules stain purple with crystal violet
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false
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list the name (genus and species) of an endospore producing organism
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Bacillus anthracis
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the reproductive structure of a fungus is _______
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Conidia
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an endospore producing organism forms a free spore. when conditions are favorable again the spore will undergo which process?
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germination
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what is an example of an organism that can be viewed with an endospore stain?
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B. subtilis
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what is an example of an organism that can be viewed with a lactephenol cotton blue stain?
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pine root
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what is an example of an organism that can be viewed with the capsule stain?
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C. neoformans
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describe what differences in appearance you would expect to see if you performed a simple staind and a capsule stain(seperate) on a capsulated organism like Klebsiella pheumoniae
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if you performed a simple stain you would only see a very small portion of the organism in the middle of the capsule due to a small amount of the simple stian that would penetrate the capsule. if you performed a capsule stain you would see the background stained and the capsule would appear as a white halo around the cell
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an encapsulated organism can often more easily cause disease than one which does not possess a capsule. explain one reason for this difference in virulence.
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capsules help many bacteria adhere to surfaces and resist flushing. if the bacteria cannot be easily flushed from the body it can more easily cause disease in a host.
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a Bacillus species is placed in a nutritionally poor environment having a temperature of 70 degrees celsius (optimal growth temperature is usually 65 degrees celsius). give the term for the process that would occur at this time.
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sporulation
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name the cellular process that would occur once an organism is again placed in a nutritionally rich environment with an ideal temperature for growth
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germination
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what is dipiocolinic acid?
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a chemical produced by endospores that is thought to lead to their high resistance found within the core of the endospore. represents about 10% of the dry weight of an endospore and it interacts with calcium ions to form calcium dipicolinate
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where is the spore in a central location?
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middle of the sporangium
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where is the spore in a subterminal location?
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b/n terminal and central
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where is the spore in a terminal location?
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to the extreme pole of the sporangium
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what protein found within an endospore is also found in human hair and nails?
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keratin
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what is the toxin produced by Clostridium tetani?
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Tetnospasmin. it affects your neurons which in turn affect the muscles of areas such as the face and jaw.
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how would a doctor treat someone who has been exposed to Tetnospasmin?
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antitoxins, antibiotics, vaccines, sedatives, and other drugs such as magnesium sulfate and beta blockers.
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where is the organism Clostridium tetani found?
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soil, dust, and animal feces.
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where would someone come into contact with Clostridium tetani?
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walking barefoot outdoors in the dirt
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how is endospore stain conducted?
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heat fix organism
place slide on staining rack flood smears with malachite green heat intermittently for 5 minutes with a butane lighter -heat only until steam rises, remove flame until there is no steam -repeat this until 5 minutes is up -dont let the dye boil or dry out -add stain as needed let slides cool, rinse counterstain with safranin for 2 minutes rinse, blot dry with kimwipe view under scope |
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how is a lactephenol cotton blue stain performed?
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always work inside the hood!
place a drop of lactephenol cotton blue in the center of the clean slide use a piece of clear scotch tape to life a fungal colony place tape sticky side down onto the glass slide view under scope |
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how is a capsule stain performed?
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place hanging drop of speciment onto the slide
place coverslip over the drop press down gently on the coverslip place drop of india ink on edge of coverslip view and record observations |
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BE SURE TO VIEW ALL EXTRA FOLDERS ON BLACKBOARD AND STUDY ALL PICTURES
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!!!!!!!!!!
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