In the grams staining method identify the following reagents

In the gram\'s staining method identify the following reagents: be very specific:

a the counter stain ___________

b the mordant _______________

c the primary stain __________________

d the decolorizing agent _________________________

Solution

In the gram\'s staining method identify the following reagents: be very specific:

a the counter stain _safranin__________

b the mordant __iodine_____________

c the primary stain __crystal violet________________

d the decolorizing agent ____ethanol_____________________

Reason:

Gram staining: This is a bacterial staining technique was investigated by scientist Christian Gram. It is used to identify and classify the bacteria based on the cell wall fluorescence. Normally bacterial peptidoglycan cell wall is negative and stained with crystal violet dye (primary stain) and if it retains the dye in the presence of iodide (mordant which fixes the dye to the cells). Then it is said to be Gram (+) positive and if it does retain the pink colour after adding a counter stain (safranin) then it said to be Gram (-) negative. Iodide used to fix crystal violet dye by reacting with the dye (Iodide (Ior I3) interacts with CV+) inside the heat fixed bacterial smear therefore, dye can be easily loaded into the dead bacterial cells to visualize under the microscope. If the omission of iodide has done and leading to inability of crystal violet dye to trap it in the bacterial cell therefore, staining cannot be achieved.

Safranin is the counter stain used. After alcohol or acetone washings of heat fixed bacterial smears, It is necessary to retain the pink colour after adding a counter stain (safranin) then it said to be Gram (-) negative. Other than safranin, Carbol fuchsin is sometimes used to identify anaerobic bacteria.