I. Gram Stain
C. The mechanism by which Gram-positive cell walls resist decolorization
is not fully understood.However, it is thought that
1. Gram-positive cell walls, upon alcohol treatment may become
dehydrated, and the _______________________________________
_________________________ behind the thick peptidoglycan
layer.
2.In contrast, Gram-negative cell walls have ____________________
___________________________ and it is thought that
the alcohol may extract these lipids, making the __________________________
__________________________________________________.
D. It is very important to perform the Gram stain on __________________
___________________ because as Gram-positive cells
age, they may loose their ability to retain the crystal violet dye.
II. Acid-fast stain
A. Used to detect cells capable of __________________________________
_______________________________________________________.
1. Cells that can retain this stain are termed ____________________.
2. Acid-fast cells have a _______________________________,
in specific they contain a great deal of a waxy lipid called
____________ ________________.
B. Important for identifying bacteria in the genus ______________________
(e.g. Mycobacterium leprae and Mycobacterium tuberculosis,
which are the pathogens responsible for ________________________________________).
C. The cell wall integrity is destroyed in dead cells so it is important
to perform this staining procedure on _________________________________.
