Busy. Please wait.

show password
Forgot Password?

Don't have an account?  Sign up 

Username is available taken
show password


Make sure to remember your password. If you forget it there is no way for StudyStack to send you a reset link. You would need to create a new account.
We do not share your email address with others. It is only used to allow you to reset your password. For details read our Privacy Policy and Terms of Service.

Already a StudyStack user? Log In

Reset Password
Enter the associated with your account, and we'll email you a link to reset your password.
Don't know
remaining cards
To flip the current card, click it or press the Spacebar key.  To move the current card to one of the three colored boxes, click on the box.  You may also press the UP ARROW key to move the card to the "Know" box, the DOWN ARROW key to move the card to the "Don't know" box, or the RIGHT ARROW key to move the card to the Remaining box.  You may also click on the card displayed in any of the three boxes to bring that card back to the center.

Pass complete!

"Know" box contains:
Time elapsed:
restart all cards
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.

  Normal Size     Small Size show me how

Microbiology lab

terms for microbiology lab

visible population of microorganisms living in one place colony
method of culturing microorganisms in which a sterile inoculating loop is used to spread an inoculum across the surface of a solid medium in petri dishes streak plate
glycocalyx composed of repeating units of organic chemicals firmly attached to the cell surface capsule
In general, what effect does the presence of capsules have on the pathogenicity of bacteria? Why? The WBC cannot phagotosize the bacteria on surface of bacteia is antigens-recognize as foreign, covers antigens, body can't recognize as foreign.
What role does the capsule play in the formation of plaque on your teeth? They enable oral bacteria to colonize the teeth, where they produce acid and cause decay, food and sugar trapped in capsule, bacteria cause plaque, cause decay.
what is meant by binomial system of nomenclature? two names
What are the parts of a scientific name? Genus species
Give the rules for capitalizing and underlining (italicizing) a scientific name. Capitalize first lette of genus, underline scientific name.
To what family of organic compounds does agar belong? carbohydrate, polysaccharide
For what specific purpose is agar used in the micro lab? solidify
What is the natural source of agar? seaweed, red algae
what five pieces of information are written on a label? your initials, your lab section, date, name of medium or test, name of organism
what does aseptic technique do? avoids contamination
liquid medium broth
Hot liquid agar can be poured into test tube to form slant
growth medium any medium that is nutrient rich
biochemical medium chemicalused to test for some kind of reaction
culture population of microbes
ubiquitious found everywhere
contamination introducing unwanted bacteria by accident into culture
sterile absence of all life
inoculate intentional introduction of bacteria into culture
incubate grow in controlled environment
culturing collecting and growing
pure culture contains only one species
mixed culture contains more than one species
eukaryotic true nucleus, more complex, bigger, more organelles, membrane bound organelles, DNA
prokaryotic no nucleus, less complex
magnification the apparent increase in size of an object viewed via microscopy
resolving power ability to distinguish between objects that are close together
compound microscope microscope using a series of lenses for magnification
binocular microscopes with two lenses
magnification of scanner objective 40x
magnification of low power objective 100x
magnification of high dry objective 400x
magnification of oil immersion objective 1000x
If you have an on onject in focus with one objective, it will be visible on all objectives, needing only a touch up with the fine adjustment. parfocal
Objects placed in the exact center of the viewing field using one objective will still be centered after changing to another objective. paracentric
rod shaped bacteria bacillus
spherical bacteria coccus
curved bacilli vibrio
corkscrew shaped bacteria spirillum
Before switching to a higher power objective, what must be th position of the specimen in the viewing field? in the center
How should the iris diaphragm be positioned for the low power objective? for the oil immersion objective? closed, partially open
How many times is th fine adjustment knob to be turned? Why is it wrong to turn it more than this? once, because you may turn it up too high and hit the lens.
negative stain staining technique used primarily to reveal bacterial capsules and involving application of an acidic dye which leaves specimen colorless and background stained
stain composed of a single dye such as crystal violet simple stain
differential stain stain using more than one dye so that different structures can be distinguished
what property of bacterial cell structure makes the Gram stain possible? bacterial cell wall
Two reasons for heat fixing? to kill the bacteria and to help them adhere to the slide
the stains of the gram stain (primary stain) crystal violet, (mordant)iodine, (decolorizer)acetone/alcohol, (counterstain) safranin
color of gram positive cells purple
color of gram negative cells pink to red
critical step in gram staining timing of the decolorizer
When opening a culture tube, what is the purpose of flaming the mouth of the tube? to prevent other bacteria from entering tube, prevents contamination by using heat currents
what is the purpose of flaming the loop? to sterilize it
Gram stains are not done on older cultures of bacteria, because old gram positive bacteria do not give reliable results, why? older cells can bleach easily making them look pink instead of purple
in the acid fast stain a simple of differential stain? differential stain
What is the purpose of the acid fast stain it stains cells of certain baceria that cause diseases that do not readily stain with the gram stain
Name two important diseases caused by acid fast bacteria, write the scientific name for each tuberculosis, leprosy, Mycobacterium tuberculosis, Mycobacterium lepral
bacterial cells that re metabolizing and reproducing rapidly vegetative cells
what are endospores? dormant, highly resistant cells formed in cytoplasm of bacteria and can survive environmental extremes such as desiccation, heat, and harmful chemicals
what is the benefit for bacteria to be able to form endospores? let bacteria survive adverse environmental conditions, protect the DNA
how long can endospores survive? indefinately
name two genera of endospore-forming bacteria that are medically important? Bacillus and Clostridium
Name two medically important genera of bacterai that are acid fast? Mycobacterium and Nocardia
Ziehl-Neelson method use heat to force stain in
critical step in acid fast stain successly forcing the primary stain inside the cells
the stains of the acid fast stain (primary)carbolfuchsion, (decolorizer)acid-alcohol, (counterstain)methylene blue
inoculating a sterile slant in a zigzag motion ordinary slant
purpose of an ordinary slant obtain maximum growth
Why do ordinary stains not work on acid fast bacteria? they have cell walls high in lipid content
Method used for the acid fast stain Ziehl-Neelsen
the four colony shapes punctiform, circular, irregular, rhizoid
the four colony margins entire, lobate, erose, undulate
colony pigment color observed with naked eye, not white, gray or off white
colony density dense colonies will appear to be balck or dark brown when using dissection scope because they block the light
broth characteristics turbid, pellicle, ring, sediment
slant characteristics filiform, beaded, spreading
Created by: jennyjustis2000