Download Lab Quiz Material 3.4

Lab Quiz 4
(3.4, 3.5, 3.6 & notes)
pp. 167-170, 320-322, 65-68
What is the purpose of staining bacteria?
What is the consequence of overstaining / understaining?
You have a coccus and rod of similar volume which is more likely to survive in a dry environment / moist
environment?
What is a basic dye? List some. What structure will it stain?
What is an acidic dye? List some.
What would the outside/inside of a cell look like after staining with eosin and methylene blue?
What kind of stain is the Gram stain?
Which is the primary stain and which is the secondary stain?
How fresh should a culture be for the Gram stain?
Why do some bacteria stain purple and is this Gram positive or negative?
Why do some bacteria stain pink and is this Gram positive or negative?
What is the most important step of the Gram Stain?
In a Gram stain what would be the effect of
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Failure to add iodine
Failure to add decolorizer
Failure to add safranin
Reversal of crystal violet and safranin
What is the color of the cells throughout the Gram Stain?
What happens is the periplasmic space?
What are the advantages of a negative stain rather than a positive stain?
What is the purpose of heat fixation?
With ideal nutritional needs met, why would a cell divide?
What is the charge of a bacterial cell?