Question

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question 38
which is the correct order for the application of reagents in the gram stain?
a iodine, safranin, crystal violet, alcohol/acetone
b crystal violet, iodine, alcohol/acetone, safranin
c crystal violet, safranin, iodine, alcohol/acetone
d crystal violet, alcohol/acetone, iodine, safranin
e safranin, crystal violet, alcohol/acetone, iodine

Explanation:

In Gram - staining, the first reagent is crystal violet which stains all bacteria purple. Then iodine is added as a mordant to form a crystal - violet iodine complex. Next, alcohol/acetone is used as a decolorizer. Finally, safranin is applied to stain the decolorized Gram - negative bacteria pink.

Answer:

B. Crystal violet, iodine, alcohol/acetone, safranin