Microbiology 020 - General Microbiology » Fall 2020 » Acid Fast Stain

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Question #1
Which of the following would likely stain negative for the acid fast stain?
A.   Mycobacteria leprae
B.   Mycobacteria phlei
C.   Escherichia coli
D.   Nocardia spp.
Question #2
What is the causative agent of tuberculosis?
A.   Escherichia tuberculosis
B.   Mycobacteria tuberculosis
C.   Bacteria tuberculosis
Question #3
What is the causative agent of Hansen's disease?
A.   Escherichia coli
B.   Mycobacterium leprae
C.   Mycobacteria phlei
Question #4
Why is heat applied during the acid fast stain?
A.   Heat is needed to loosen the waxy mycolic acid layer so the staIn can penetrate
B.   Heat is needed to somehow melt the waxy mycolic acid layer so the staIn can penetrate
C.   Heat is needed to solidify the waxy mycolic acid layer so the staIn can penetrate
Question #5
Match the following : Primary stain
A.   Acid-alcohol
B.   Methylene blue
C.   carbolfuchsin
Question #6
Match the following : Decolorizer
A.   Methylene blue
B.   Acid-alcohol
C.   carbolfuchsin
Question #7
Match the following : Counterstain
A.   Acid-alcohol
B.   Methylene blue
C.   carbolfuchsin
Question #8
What would be the outcome for an acid fast negative bacteria if you skip the acid-alcohol step? What color would you observe under the microscope?
A.   pink
B.   white
C.   red
D.   yellow

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