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37 Cards in this Set

  • Front
  • Back
What is the differential step and Gram staining?
Decolorizer or iodine
What does grams iodine do for the stain?
Fixes the crystal violet color to the outer layer of peptidoglycan
What color are gram-positive cells at the end of the stain?
What color are gram-negative cells at the end of stain?
What color was human cells be at the end of the stain?


You decide to Gram stain some of your own cheek cells. Are they gram-positive or gram-negative? Why?
Gram-negative; they do not have a peptidoglycan cell wall
Describe how you do positive controls for your Gram stain, eliminating all variables.
Do three smears on a single slide, including a known positive, unknown, and known negative.
Acid fast cells: choose all that apply:

- contain acid in their cell walls 30

–contain acid in their cytoplasm

- Are not human pathogens

- turn pink

- turn green or blue

- turn pink

- contain acid in there cell walls

The decolorizer used in the Gram stain, and the decolorizer use any acid fast stain, are the same, true or false?
It is okay to give baby cookies containing honey because they have been baked, true or false?


Anthrax will test positive in the endospore stain, true or false?


The Gram stain is a ______ stain. That means that some bacteria will stay in one color, while other bacteria will stain a different color


Grams iodine is a "_____," a fixer of color


The gram-positive cell has a thick layer of peptidoglycan on the surface, the crystal violet– iodine complex binds tightly to it, and is/is not removed by the decolorizer.
Is not
Why does the iodine not bind to the crystal violet sufficiently in a grand negative cell?
Because the gram-negative cell has a thinner layer of peptidoglycan protected by a lipid bilayer. This allows the decolorizer to be able to pull the crystal violet away from the cell, leaving it clear.
It is very important to remember that as a sales age and begin to die, they stop building their ________. This means that cultures that are too old (older than 48 hours, but sometimes older than 24 hours) will not sustain Graham positive, even though they are Graham positive if you stain them when they are 12 hours old.
Peptidoglycan layer
What is the proper way to do a Gram stain in order to eliminate variables in the staining, so that you know your results are reliable? What kind of control is this?
Include a known gram positive and known gram-negative on the same slide; positive

Crystal violet and safranin are both "basic stains" that can be used as simple stains, and will stain all cells. How can they be used here, then, in a different stain technique?

By including a differential step/wash
The term "fast stain" does not refer to the speed of the stain, but rather the fact that some bacteria have ________ in their _________. These acids hold fast to a _______ stain, and do not let the stain wash off the cell when washed with an ________ wash.
Mycolic acids; cell walls; carbolfuchsin; acid-alcohol
Acid fast stains are clinically important because two important human pathogens are caused by mycobacteria. What are they?

In addition, _______ are also acid-fast.

Tuberculosis, leprosy; cryptosporidia
What are the names of the two common methods for doing acid fast stains?

Ziehl-Neelson method; Kinyoun method

The Ziehl-Neelson method uses _______ to drive the ________ into the _______.

The Kinyoun Method uses a more concentrated solution of ________ to achieve the same result without ______.

steam; carbolfuchsin; cell wall

carbolfuchsin; steam

Of the two common message for acid fast stains, which uses steam?


What is the differential step during the acid fast stain experiment?
Acid-alcohol decolorizer
By either of the two common methods for doing acid fast stains, carbolfuchsin is what color?


When you are doing an acid fast stain, you are looking for bacteria that contain _______ acid in their cell walls. To find these kind of bacteria, you use the stain ______, because cells containing this kind of acid do not let this stain wash off the cell wall when it washed with an acid-alcohol wash.

mycolic; carbolfuchsin

My colic acid positive cells are what color? The counter stains are usually _______ or ________, which stain the negative cells


Brilliant green, methylene blue

What color would a mycolic acid negative cell be?
Either blue or green
Note to that in an acid fast stain, ______ is positive for mycolic acid, and ________ is negative for mycolic acid. (colors)
pink; green or blue

Some bacteria are able to form _______, a protected, dormant form of bacteria that contains the genetic information and are able to survive unfavorable conditions, such as dryness. As these are being made, they exist with the parent bacteria, and are called _______.
Spores; endospores

Some bacteria are able to form spores, a protected, dormant form of bacteria that contains the __________ and are able to survive unfavorable conditions, such as dryness. As these are being made, they exist with the _________, and are called endospores.

genetic information; parent bacteria

What is the name of the protein that protects the spores?
Kratin and is resistant to staining, so the endospore stain must use either _______ or a ________ to achieve results

steam; long incubation time

When performing an endospore stain, you are searching for a bacteria that contains ______. These a protected by a protein, _______, which is resistant to staining. To detect these, you use the stain ________, which binds to the protein coat, and then decolorize to identify

spores; keratin; malachite green.

What is the name of the common stain used for endospore staining? How does it work?

Malachite green; binds to the protein coat of the endospore

Endospire stains can be useful clinically because _____, bacteria which causes anthrax, can form spores. In addition, so can _______ and ________.

bacillus anthracis; clostridium botulinum; clostridium tetani

It is very important not to give babies under a year old honey, because?
Honey contains clostridium botulinum spires, which are not killed by pasteurization or by cooking. The acidity of an adult stomach, however, is enough to destroy the spores