Term
| What do individual colonies on a plate represent? How is this helpful for microbiologist? |
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Definition
Colonies represent a single microbe.
This could tell a microbiologist how abundant a type of microbe is in a given area. |
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Term
| Do colonies on the plate represent all microbe present in the environment you sampled? |
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Definition
| No the conditions on the plate could inhibit certain bacteria from growing. |
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Term
| Where is using steril technique important? |
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Definition
| Bathroom, Kitchen, emergency room. |
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Term
| How could you be certain a media is steril |
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Definition
place the media in an autoclave to kill all microbes present.
Positive control-placing an organism on the plate that i knew would grow to make sure the media would grow the organism
Negative control- I would only put the media in a dish and no microbes on it and see if anything grew, if anything grew I would know the media isnt pure. |
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Term
| How could you determine a culture contains only one kind of organism? |
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Definition
| I would prepare several dishes with the same culture and allow them to grow. After growth occured I would make sure all colonies are uniform. To be extra sure i could take a sample from one of the dishes and prepare my own culture. |
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Term
| Why are basic stains used more often in simple staining procedures rather than acid fast stains? |
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Definition
| Since the bacterias' cell wall has a negative charge and the positive charged cation of the basic stain is usually colored attaches to the cell wall. The acid stains cation is colorless so it wouldnt provide a contract to see the microbe. |
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Term
What is the value of a simple stain?
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Definition
| Shows the cells shape and arrrangement along with cell structures |
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Term
What is the value of a gram stain?
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Definition
| a gram stain would show if the bacteria is gram negative or positive (presence of peptidoglycan or an outer membrane) |
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Term
| Why is it important to heat or chemical fix you a sample before staining? |
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Definition
| It prevents the sampe from being washed away during the staining process. It also kills the microbes. |
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Term
| If you do a gram stain and notice that some of the adjacent cells were a different color what would you assume? |
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Definition
| I would assume the adjacent cells are dead becuase dead cells dont gram stain like live cells do. |
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Term
if you view a gram stained field of purple rods and red cocci what would you assume?
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Definition
| I would assume there are two different types of microbes present in the sample. |
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Term
| why might a physician preform a gram stain? |
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Definition
to see the compostition of the cell wall to best decide how to attack the bacteria.
it would also show the shape of the cell and that would help in deteremining what the cells are and help with diagnoising the patient |
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Term
| adavantages to pour plate method |
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Definition
| allows for the quantity of microbes to be obtained |
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Term
| advantages to a streak plate method |
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Definition
| you can grow colonies for further tests of classicifcation to be done |
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Term
| disadvantage of pour plate method |
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Definition
| doesnt allow the observer to see colony morphology |
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Term
| steak plate disadvantages |
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Definition
| not always useful in determining quantity of microbes |
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Term
| why dilluting and isolating bacteria would be useful skills to have |
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Definition
isolating makes it possble to look at a single type of bacteria
it could also allow to see how infected an individual is by seeing how many bacteria present in a colony |
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Term
| why woud pour plate and streak plate methods be done simutaneously? |
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Definition
| youd be able to see how many organisms are present and you would be able to have sample of the bacteria that can be used for looking under a microscope. |
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Term
| How would the colonies at the top of the streak plate differ from those inside the agar of the pour plate? what might this tell you about the organisms ideal conditions? |
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Definition
organisms on the streak plate would show organisms that can survive in the presents of oxygen. it would also show how the organisms grow and their color.
the pour plate can show which organism can live without the presents of oxygen and where the ideal conditions for the microbe are. |
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Term
| difference between selective and differential media |
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Definition
selective media prevents growth of certain microbes while supporting the growth of others
differential media allows you to determine between different kinds of bacteria by using various nutrients and seeing how the bacteria react with the media. |
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Term
| what is the purpose of peptone and agar in the media |
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Definition
| these provide the nutrients for the microbes to grow, proteins amino acids that promote growth. agar also offers a buffer for the microbes. |
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Term
| how can physical conditions be used to isolate bateria |
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Definition
| some bacteria cant survive in some types of environements like high salt of low pH. so by putting the microbe in these conditions only certain bacteria can grow while others wont be able to |
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Term
| Why are protozoa that are parasitic hard to treat compared to a bacterial infection? |
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Definition
| protozoa are eukarotic and their cell membrane composition is very similar to body cells so its hard to find a target for treatments to attack that doesnt harm the bodies cells. |
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Term
| why are contractile vacuoles needed by these organisms (osmotic gradient) |
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Definition
| these vacuoles control how much water comes in and out of the organism. so if the organism gets put into and environment of high salt concentration the vacuoles would control the release of water to prevent death of the organism. |
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Term
| why are protozoa and bacteria placed into different kingdoms? |
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Definition
protozoa have a nucleous and no peptidoglycan
bacteria dont have a nucleous and has peptidoglycan |
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Term
| what are the advantages of being able to distinguish between protozoa? |
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Definition
| it allows for more effective treatment of a patient because different types of protozoa react differently to different treatments. |
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Term
| why can you see a euglena red "eye spot" in photosynthetic strains? |
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Definition
| the spot filters sunlight in the photosynthetic structures. if the euglene is not photosynthetic it wont have this spot. |
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Term
| what does the cleaning around the bacteria mean in a strach hydrolysis assay? what is going on in the space and what is responsible for this reaction? |
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Definition
| the cell produced and exoenzyme (lysozyme) to go out and break down the starch around the cell into smaller parts for the cell to take in. the clearing is the area where the exoenzyme broke down the strach. |
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Term
| what is carbohydrate catabolism |
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Definition
| it is the breaking down of carbohydrates into smaller parts for the cell and it makes ATP |
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Term
| is the strach hydrolysis differential or selective media? |
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Definition
| differential it contains starch so it will help distiguish which cells can break down the starch with an exoenzyme and which ones cant. |
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Term
| why do we freeze and refridgerate food |
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Definition
| we do this to lower the foods temperature and hopefully put all the microbes present on the food below their miniumum temperature so they wont be able to replicate. |
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Term
| which type of bacteria could theoretically grow in a fridge? |
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Definition
| psychrophies would grow best because their optimum temperature is lower than the other type of bacteria |
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Term
| what is the purpose of heating food? |
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Definition
| to raise the foods temperature above any bacterias maximum temperature so they cant replicate anymore. |
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Term
| why is turbidity not an accurate measurment of viable bacteria in a culture |
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Definition
| because dead bacterial relfect light just as well as live bacteria do and there is do determining which ones are alive and which are dead by just looking at turbidity |
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Term
| which bacteria would grow best in the human body? |
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Definition
| mesophiles becuase their optimum growth temperature is 37 degrees C E. coli for example |
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Term
| give and example of positive and negative consequences of bacterial transformation |
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Definition
Superbugs-super resistance
creation of bacterai that can be helpful to people, like bacteria that make insulin |
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Term
| what are ways that bacterial DNA can be changed or mutated outside the lab setting |
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Definition
| mutations caused by chemical mutants or wrong congugate pairs |
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Term
| mechinisims which antimicrobial agents kill of inhibit microbes |
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Definition
| inhibition of: protein synthesis, plasma membrane synthesis, cell wall formation through peptidoglycan, and DNA synthesis |
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Term
| why is it important for healthcare providers to understand how antimicrobial drugs work and which pathogens are sensitive to which antimicrobial drugs |
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Definition
| knowing this will determine which drug and at which concentration needs to be perscribed by the health care provider to an infected patient. allows for efficient treatment. |
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Term
| from the disk experiment can we determine is an angent is bacteriocidal or bacteriostatic |
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Definition
| no, this just shows that it inhibited the replication of the microbe, to determine if it is stactic or cidal youd have to take a sample from the clearing and put it on a nutrient plate and see if anything grows. if there is growth is was static if nothing grows it was cidal. |
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Term
| what is the difference between bacteriocidal and bacterical static agents? |
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Definition
cidal-kill bacterial cells-used for cleaning medical equipment
static-temporarily prevents bacteria from replicating- used in mouth washes so we dont kill the bacteria we need in our mouth. |
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Term
| examples of physical conditions that can alter the actions of disinfectants |
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Definition
time of exposure- the long an agent is in contact with a surface the more microbes it has time to kill
number of microbes- the more microbes present the longer it will take for the disinfectant to work |
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Term
| what type of antimicrobial agent is alchol, what kinds of microbes does it kill? what can it not inactivate? why? |
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Definition
alchol is an antiseptic
it kills/inactivates- bacterial cells and fungal cells nonenveloped viruses.
it is not effective against- endospores or non enveloped viruses.
this could be becuase these lack the target or dont allow the alchol to come into contact with the target alchol attacks. |
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Term
| what is the difference between epidemic and endemic |
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Definition
endemic is always present in a popualtion
epidemic is when many people in a given area acquire a disease in relatively short period of time |
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Term
| what are fomite and vectors |
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Definition
fomites are objects that become contaminated with a disease, glasses, sheets and blankets
vectors are insects that carry disease mechanically, on their feet and biologically, by biting. |
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Term
| do all people who come into contact with a disease acquire the disease |
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Definition
| no, the person could have an immune system that fights the disease or they may have the necessary antibodies to fight the disease. they may also not come contact with enough microbes to get sick. |
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Term
| what are communicable diseases and noncommunicable diseases |
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Definition
communicable-can be transmitted directly or indirectly to another host. chicken pox
non- generlly cant be transmitted to another host unless the body is weakend. cadiovascular diseases |
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Term
| how can a healthcare provider help to not transmit disease |
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Definition
wearing gloves and changeing gloves between patients
washing hands
being aware of blood and droplets on clothing that could come into contact with patients or other healthcare providers. |
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Term
| what is agglutination and hemoglutination |
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Definition
agglut-clumping of bacteria by antibodies
hemo-clumping of red blood cells by antibodies |
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Term
| what are antibodies? how are they formed? how can the used to identify different types of cells? |
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Definition
| proteins produced by the body. the combine with specific antigens, by looking to see if there is clumping in a sample after antigens have been exposed you can distiguish between cells |
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Term
| what structures on your blood cells determine you blood type? why are these important? |
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Definition
| antigens determine blood type they are important for antiboides to bind to. |
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Term
| how would agglutination reactions be used to locate the source of an epidemic |
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Definition
| by seeing if an idividuals bllod has the necessary antibodies to cause agglutination with the disease antigens you would be able to tell in the individual had been exposed to the disease. |
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Term
| how can agglutination be helpful to healthcare providers |
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Definition
the clumping reduces the number of infectious units that have to be destroyed=more efficiency
helps with diagnoising a patient. |
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