Concept explainers
To write:
The omitted step in a Gram stain method that allow differentiation of Gram-positive and Gram-negative cells.
Given:
“Gram stain” “differentiation “and “omitted step”
Introduction:
In 1884, the Danish scientist Hans Christian Joachim Gramis discovered the
The main principle of Gram stain is used to differentiate based on the color retaining ability of the stain. Gram-positive bacteria retains crystal violet and appears violet or purple in color under the microscope. Since, the cell wall of Gram-positive bacteria contain thicker peptidoglycan layer. So, it retains the stain during ethanol decolonization step. Whereas in the Gram-negative with thinner peptidoglycan layer denatured during ethanol step and retains the secondary stain (safranin) and appears pink color under the microscopic examination.
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