UNIT 2 GRAM STAINING

Question 1

Fundamental Staining Method in Bacteriology

Answer 1

GRAM STAINING

Question 2

Developed by

Answer 2

Hans Christian Gram

Question 2

involves the use of:

Answer 2

○ Primary stain
○ Mordant
○ Decolorizer
○ Secondary stain

Question 2

determines the Gram-staining characteristics of a species

Answer 2

Cell wall structure

Question 3

PRIMARY STAIN

Answer 3

CRYSTAL VIOLET

Question 3

MORDANT

Answer 3

GRAM’S IODINE

Question 4

DECOLORIZER

Answer 4

95% ETHANOL or
ACETONE-ALCOHOL

Question 5

SECONDARY STAIN

Answer 5

SAFRANIN O or
CARBOL FUCHSIN

Question 5

95% ETHANOL or
ACETONE-ALCOHOL in gram - color

Answer 5

colorless

Question 5

SAFRANIN O or
CARBOL FUCHSIN in gram - color

Answer 5

Red/dark
pink

Question 6

bacteria appear pink
under the light
microscope

Answer 6

GRAM-NEGATIVE

Question 7

retain the primary crystal
violet stain during the
decolorizing treatment
and appear purple. (blue
to purple)

Answer 7

GRAM-POSITIVE