Study of Prokaryotic cell using Gram staining technique
Aim : to stain and observe prokaryotic cell in the given sample by gram
staining method.
Introduction : Gram staining technique was introduced by Hans
Christian Gram in1884. It is the first method used in the studies of
bacteria. Based on gram staining technique bacteria can be classified
into gram positive and gram negative bacteria. The bacteria which stain
bluish purple color are gram positive while those in pinkish red color
are Gram negative bacteria.
Requirements : Crystal violet stain ,Gram iodine solution, Decolouriser
(70% alcohol) and saffronine solution, microscope ,dropper, sample
(curd or tartar)
Procedure : Take a clean toothpick and remove the tartar from
between the teeth. Place the tartar on the slide. Make a smear and
follow the procedure as given in the chart. One can use even curd as a
sample.
Observation : In the given tarter sample one can see both bluish as well
as pink colored cell which were circular in shape.
Inference :The cell wall of bluish color cells has a thick layer of
peptidoglycan hence it retains violet color and so are called as gram
positive bacteria. Whereas the cell wall of pink color cells has thin layer
of peptidoglycan and lipid layer hence the solvent disturbs the cell wall
and decolorizes the cell ,further takes saffronine solution and appears
pink in color and hence indicates gram negative bacteria.
Aim : to stain and observe prokaryotic cell in the given sample by gram
staining method.
Introduction : Gram staining technique was introduced by Hans
Christian Gram in1884. It is the first method used in the studies of
bacteria. Based on gram staining technique bacteria can be classified
into gram positive and gram negative bacteria. The bacteria which stain
bluish purple color are gram positive while those in pinkish red color
are Gram negative bacteria.
Requirements : Crystal violet stain ,Gram iodine solution, Decolouriser
(70% alcohol) and saffronine solution, microscope ,dropper, sample
(curd or tartar)
Procedure : Take a clean toothpick and remove the tartar from
between the teeth. Place the tartar on the slide. Make a smear and
follow the procedure as given in the chart. One can use even curd as a
sample.
Observation : In the given tarter sample one can see both bluish as well
as pink colored cell which were circular in shape.
Inference :The cell wall of bluish color cells has a thick layer of
peptidoglycan hence it retains violet color and so are called as gram
positive bacteria. Whereas the cell wall of pink color cells has thin layer
of peptidoglycan and lipid layer hence the solvent disturbs the cell wall
and decolorizes the cell ,further takes saffronine solution and appears
pink in color and hence indicates gram negative bacteria.
