Laboratory Exercise 4 Acid Fast Stain

Question 1

This is used to detect bacteria with mycolic acid attached to the cell wall

Answer 1

Acid fast stain

Question 2

This primary stain of the acid fast stain contains phenol which penetrates the waxy cell wall

Answer 2

Carbol fuchsin

Question 3

Acid Fast Stain (Ziehl-Neelsen Stain)
CHAM

Answer 3

Carbol Fuchsin (1 min) - primary stain
Heat (5 min) - mordant
Acid Alcohol (10-15 sec) - decolorizer
Methylene Blue (1 min) - counterstain

Water in between

Question 4

Acid fast vs non acid fast bacteria color

Answer 4

Acid fast - pink/red
Non acid fast - blue/purple