Lab Smear And Stain Flashcards
A Danish bacteriologist who developed a staining technique that separates bacteria into two groups
Hans Christian gram
Two group that Christian Gram developed
Gram positive and gram negative
The procedure is based on the ability of microorganisms to retain the purple color of crystal violet during decolorization with alcohol.
Gram stain
are decolorized by the alcohol, losing the purple color of crystal violet.
Gram negative bacteria
are not decolorized and remain purple
Gram positive bacteria
What are the reagents of gram stain
Crystal violet, iodine, acetone alcohol and safranin
Gram positive cocci is color
Violet or purple
Gram negative bacilli is color
Pink
In gram positive crystal violet it stained as
Violet or purple
In gram positive in iodine it stained as
Violet or purple
In gram positive acetone alcohol it stained as
Violet or purple
In gram positive safranin it stained as
Violet or purple
What is the primary stain/initial stain of gram stain
Crystal violet
What is the mordant of gram stain
Gram’s iodine
What is the decolorizer of gram stain
Acetone alcohol
What is the counterstain/secondary stain of gram stain
Safranin red
In gram negative crystal violet stained as
Violet or purple
In gram negative iodine it stained as
Violet or purple
In gram negative acetone alcohol stained as
Colorless
In gram negative safranin stained as
Pink
duration time of crystal violet in gram staining
1 mins
duration time of iodine in gram staining
2 mins
Duration time of decolorizer in gram staining
30 sec
Duration time of safranin red in gram staining is
1 min
