Microbiology Lab midterm review-1,26,3,4,5,7,11,20 Flashcards
Fixing of bacteria to a slide is done by passing the bacterial smear over the flame of a Bunsen burner BUT it can also be chemically done using
What type of information below cannot be determined by a simple stain?
a. thick/thinness of a cell wall
b. cell arrangement
thick/thinness of cell wall
True or false. When making a smear from solid media you must mix your bacteria in a small amount of water first.
What is the name of the mordant in Gram-staining called?
Gram negative cells will show the color of the ____ stain after gram staining
What is the name of the apparatus you use in class to sterilize your inoculating tools?
There are 2 dilution techniques. Which technique does not allow you to quantify?
a. pour plate
b. streak plate
c. spread plate
__________ is the most common isolation technique.
streak plate technique
After Gram-staining cells appear pink. What does this tell you about the bacterial cells?
the cells have a thin wall
The ideal age that a bacterial culture should be used for staining is?
In the spread plate method colonies grow on and in the agar or only on the surface?
only on the surface
Turbidity can be used using a machine called a ______________.
What happens to the % of transmittance as a microbial cell population in nutrient broth increases?
What happens to absorbance as a microbial cell population in nutrient broth increases?
In determining bacterial level cells/ml you should choose an agar plate that contains between _________ colonies.
Generation time is the time required for a ___________?
cell to divide into 2 cells
In Gram staining the safranin is the __________.
The shorter the generation time the ________ the growth.
A chromophore is the _____________.
the ion that is colored
A pure culture is one that?
only contains a single kind of microbe
The iris diaphragm can be found _______ the __________.
below the condenser
In a Brightfield microscope
dark objects are viewed against a bright background
In a parfocal microscope where the specimen has been focused at low power will only need minor adjustment by using the __________ as you increase the magnification.
fine adjustment knob
If the total magnification of your specimen is 400x which objective lens was being used?
high dry lens
What happens to the field of vision as you change your objective lens from low power to the scanning lens?
Agar is a solidifying agent that is extracted from?
Which of the following type of media is used to grow bacteria that require small amounts of oxygen?
A bacterial organism was introduces into a tube of nutrient broth which has been allowed to sit at 30*C for 24 hours. After this time it is observed to have clumps of microbial cells suspended in the broth while the remainder appears cloudy. What bacterial growth pattern is this exhibiting?
Which of the following is solid media?
a. nutrient broth
b. Agar slant
c. Agar deep
Permanent bacteria that can reside and multiply are
liquid media is?
cloudy as a result of bacterial growth is?
intentional introduction of microbes onto or into media
steam sterilization under pressure
population of cells arising from a single bacterial cell
substance that turned red when metabolized by bacteria
bacteria that reside temporarily and cannot multiply
What tool should be used to introduce microbes into an agar deep?