Question

what effect do you suspect the following will have on your judgement of the gram reaction of an organism?

Staining a thick smear made from an uneven cell suspension: what will be observed and why?

Answer 1

What effect do you suspect the following would have on your judgment of the Gram reaction of an organism?

Using an old Gram's Crystal Violet preparation containing crystalized dye	When use a old stain, definitely it will precipitate on your slide and can mislead you about the results, like you may record the gram negative as gram positive organism
Increasing the length of time for counterstaining.	When increase the counterstaining time, the organism will going to stain pink, so you will record it as gram negative.
Destaining with ethanol for one minute.	You will end up in decolorizing the bacteria, so it will take up pink color and look like gram negative.
Substituting aqueous crystal violet for Grams' Crystal Violet.	The aqueous crystal violet will not going to deposit and it will be washed away. So you will record the bacteria falsely.

Staining a thick smear made from an uneven cell suspension: what will be observed and why?

When you stain thick smear, the stained bacterial will be extremely dark, and you will not be able to see any bacteria as it will have overlapping cells with uneven thickness. So, you may record them as gram positive.