This site is 100% ad supported. Please add an exception to adblock for this site.

Microbiology Lab Test 1


undefined, object
copy deck
What is the procedure for handling samples to prevent contamination by microorgansims in the environment?
aseptic technique
What are organisms that grow and multiply in a container of culture medium?
What is the media of agar and nutrients for sampling the surface of the environment?
What is the basic medium that contains nutrient and agar only?
TBAB plate
What is the lens closest to the viewer in a compound light microscope?
ocular lense
What is the lends in a compound microscope that is closest to the specimen?
objective lense
What is the lens system that is located below the microscope stage that directs light rays up through the specimen?
What is the shutter-like structure within the condenser that regulates the amount of light that reaches the specimen?
iris diaphragm
What is the flat platform between the upper lens system and lower set of devices for providing light with a hole in the center allowing light to pass through?
What is used to make great changes in raising and lowering the stage?
coarse adjustment
What is the small outer know used only for adjustments when looking through the microscope on oil immersion?
fine adjustment
What is the amount a viewed specimen is enlarged by a lens?
What is 10x on the microscope?
The objects is viewed ten times larger than it appears normally through the unaided eye.
What is the magnification of a specimen, determined by the multiplication of ocular lens by the objective lens objectives?
total magnification
What is the numerical value in a lens system that indicates the amount of clearance between the slide and the bottom of the objective lens?
working distance
What is increased detail at high magnification?
What does oil immersion do?
improves resolution and does not increase the magnificaton
What allows the object to remain in focus as you swith from one objective to the other?
Why should you wash your hands if you get immersion oil on them?
What are the 7 steps of the spill procedure?
1. Notify everyone so they don't walk in it.
2.Tell the teacher
3.Flood spill with bleach
4.Glove up
5.Wipe up spill with paper towels, and then place in biohazard container.
6.Wash hands.
7. For spills on the body, use lysol soak and scrub with soap.
What is the state of being free of pathogenic organisms?
How are petri dishes stored?
bottoms up
What does TBAB stand for?
tryptic blood agar base
What is the device that is used as light source for the microscope?
the illuminator
What is the lens system composed of?
condenser,objective,ocular lenses
What does resolution allow for?
increased detail at high magnification
What is the max resolution using oil immersion lens?
What is it called that different media refract at different angles?
refractive index
What is the other name for micrometer or nanometer?
micron and millimicron
What is a micrometer equal to and nanometer?
10-6 meter
10-9 meter
What is the method to be used when measure things in micrometers?
oil immersion lens
What is the microscope to be used when something measures in nanometers?
electron microscope
How do bacteria reproduce?
Duplicate every twenty minutes, and those new bacteria duplicate after another twenty minutes.
What is the nutrient material prepared for growth of microorganisms in a lab?
culture medium
What is added to nutrient medium to make it gel-like?
What is the growth of bacterial cells on a solid medium that results from a single bacterium?
What is the external appearance of colonies in culture that include form,elevation,and margins?
colony morphology
What is the growth of microorgansims that contains more than one organism?
mixed culture
What is the growth of bacterial cells that originated as a single bacterium usually picked and transferred ?
pure culture
What is the selection of bacteria from one culture for growth in a different culture without contamination by unwanted microorganisms?
aseptic transfer
What is the creation of differences in the biochemical composition of the cell wall parallel their gram reactions?
gram stain mechanism
What is affected in organisms when a gram stain is applied?
cell wall
What type of gram organism has bacterial cell walls that are rich in mucopolysaccarides that enable the cell to resist decolorizer?
gram positive
What is the gram organism that have a cell wall high in lipid content and alcohol breaks down the lipid allowing the crystal violet-iodine complex to escape from the cell wall?
gram negative
What are three things used to identify a microbe?
1. gross appearance of its growth
2. growth requirements of its environment that are necessary for support
3.staining properties
What is the purpose of the agar streak method?
The mass of the media is diluted out through the four quads.
What quadrant is significant?
The quad D is most significant, because there will be isolated colonies grown, which can be used in id testing.
What is the purpose of the slant streak method?
The purpose for streaking is for storage of microbiologic stock.
What happens if microbiologists allow for the bacteria in a slant to consume all of the nutrients/.
They risk losing that particular line of bacteria.
What is the purpose of the broth inoculating method?
So that large quantities of bacteria can be grown in a short time.
What color do gram positive and negative cells stain?
Which gram cell walls are thick or thin?
What are the layers that make up gram cells?
Which gram cell type has an outer membrane?
gram negatives
What is a disease-causing organism?
What is when a characteristic is distinctive for a particular disease or condition?
Who invented the gram stain?
Christian Gram
What does the gram stain allow for?
visualation of the gram stain and and putting them into one of the 2 groups
What stains the bacteria purple?
crystal violet
What is a chemical that fixes chemical dyes into or onto a substance by combining with the dye to form an insoluble compound?
What color does the bacteria turn with the addition of iodine?
What chemical additive determines whether or not the bacteria will stain pos or neg?
What stains bacteria red?
Will sarfanin have any affect on microbes that have not been exposed to a decolorizer?
What can you do after you have performed an agar streak method?
1. perform gram stains
2.identify bacteria with additional biochemicals
3.perform antimicrobial susceptibility testing
What do we learn from a gram stain? (3)
1.gram reaction
2.cell shape
3.cell arrangement
Give three reasons why serial dilutions are performed.
1. Bacteria can be counted
2. Bacteria counted can be more accurate
3. There are varying numbers of bacteria in different biological sites
What are the two reasons to make sure your loop has cooled before scooping microbes?
1. could kill microbes
2. burn them into the air
What is the round cell shape name?
What is the rod cell shape name?
What is the comma cell shape?
What is the spiral cell shape?
What is the spiral cell shape with antennae?
What is the cell shape that is a cross between cocci and baccilli?
When determining cell arrangement, what should you look at?
multiple bacteria
What is the special cell wall that makes up gram cells?
What is this cell arrangement? oooooo
What is this cell arrangement?

What is this cell arrangement? oo
What is this cell arrangement?

What part of the name of bacteria should be capitalized?
the genus
What is the formula for the single dilution?
volume of the sample
vol of sample + vol of the diluent
If you streaked for isolation from a dilution of .1 ml..and get 53 colonies on the many were in the original sample?
What are the rules when counting colonies?
-Dont count any less than 30 or anymore than 300.
How do find out how many colonies are in an original sample?
1. Count all plates, and get rid of any less than 30 or more than 300.
2.Make the negative exponent positive
3.Then, make the exponents the same number.
4.Average the numbers.
5.Use the unit col/ml.
What does dichotomous mean?
two catergories and classifications
What is the purpose of the dichotomous key?
to identify an organism
How do you know if you have growth in a nutrient broth?
turbidity appears or a button
What is the process of inoculation a plate,slant,or broth from a previous plate,slant, or broth, rather than from a specimen?
What is when a plate,broth, or slant have come from a previous slant, broth, or plate rather an organism?
What is when a urine specimen is not collected using the aseptic technique?
voided urine
What is when a urine specimen is collected using the aseptic technique?
clean catch, mid stream
What is the purpose of serial dilutions?
Make counting more reliable
What are procedures designated by CDC and OSHA for handling body fluid samples?
standard precautions
What is to treat with an agent or conditions that destroy all microorganisms including viruses, bacteria,fungi,and spores?
What are spores resilient to?
heat,chemicals, and desication
What is an agent intended to destroy or irreversibly inactive specific viruses,bacteria,or pathogenic fungi, but not neccessarily spores on inanimate surfaces?
What is a chemical used on the skin to inhibit growth of microorganisms?
What is the term of capable of killing microorganisms?
What is capable of killing bacteria?
What is the term capable of inhibiting bacterial growth?
What is a procedure that eliminates or reduces microbial contamination to a safe level with respect to the transmission of infection?
What is a retrovirus believed to be the causative agent for aids?
What is a virus that often causes a persistent infection to liver and can be spread by contact with body fluids?
hepatitis b virus
What is a sealed capsule that contains endospores of an organism and phenol red?
kilit ampule
What is the purpose of the kilit ample?
If endospores survive autoclaving, and germinate, vegatative bacilli begin to multiply in broth. In this process, the bacteria uses nutrients within the vial and produce acid.
What does the PH in the killit ampule have to be to turn yellow?
at or below 6.8
If the ampule turns purple or yellow what is the reaction?
purple-successful autoclave
yellow-unsuccessful autoclave
The effectiveness of decontamination depends on what seven things?
2.time of contact
3.gram reaction of the organism
4.number of organisms present contamination of the disinfectant
6.object being disinfected
7.cost of disinfectant
What is the purpose of the dilution experiment with the decontamination?
determine effective concentration of the disinfectant
what is the purpose of the time exposure experiment with the decontaminatant?
Determines time for bacteriocidal effect of the disinfectant at the manufacturer's concentration
What does e. coli look like on a slide?
Red and pink gram - basillus
What does staphylococcus epidermis look like on a slide?
blue and gram + cocci
What is autoclaving?
steamed heat under pressure
What are some moderate resistance organisms?
protozoan cysts,fungal sex spores,viruses
What type of structure in a virus, makes them more resistant?
naked viruses are more resistant than enveloped viruses
Name two viruses that are the most resistant?
hepatitis b and poliovirus
Name some vegetative bacteria that are moderately resistant.
m. tuberculosis,s.aureus,psuedomonas
What is the amount of time required to kill a species at a given temp?
thermal death time
What is the temp at which a species dies at a given time?
thermal death point
Give 6 types of sterilizing heat. flame oven
3.boil water
5.fractional sterilization oil
What is a problem with hot-air ovens?
Dry heat doesn't penetrate materials easily and requires long periods of exposure
What is the problem with boiling?
The heat tolerance of many microbes is unknown.
What is so good about autoclaves?
-able to achieve boiling points without damage
How can you kill endospores?
fractional sterilization
How does fractional sterilization kill endospores?
Puts them in a vulnerable vegetative state
What is the drawback to hot oil methods?
Following the treatment, there is cleaning and drying- which may introduce new microbes
What does disinfection destroy?
vegetative bacteria
What are disinfectants applied to living tissue?
What lowers the microbial counts to acceptable levels,thus reducing the risk of disease transmission?
What is the mechanical removal of microbes or move them around?
When are transmission-based precautions used?
When a patient is actually known or suspected to be infected with a highly contagious or epidemiologically important pathogen.
What is a sterlizing gas that kills endospores?
ethylene oxide
What is the passage of a liquid or gas through a screenlike material with pores that are small enough to retain microorganisms-a sterilize method?
What is a moist heat process used in beverages to kill pathogenic bacteria and reduce the number of nonpathogenic bacteria?

Deck Info