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Gram's iodine stain is applied after the culture is stained with the primary stain. It acts as a mordant, fixing the primary stain to the cell wall while lending no additional colour to the cell (i.e. the mordant itself is not a stain). The mordant is only able to fix the stain to Gram-positive bacteria because of the characteristic thick, peptidoglycan coat that they possess. Because the mordant is not able to fix the stain to Gram-negative bacteria (who's coat have a different composition), the crystal violet stain will wash away from Gram-negative bacteria when the decolourizing agent is added.
Wiki User
∙ 15y ago
Wiki User
∙ 14y agoMordants are used in gram staining to bind to dye and make it less soluble. For example in staining flagella a mordant is used to thicken the flagella fiber until our eyes can see it.
Wiki User
∙ 14y agoThe mordant in the negative staining procedure is Gram's iodine.
Wiki User
∙ 11y agoGram's iodine is called a mordant because it fixes the primary stain to the cell wall and adds any color.
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∙ 15y agoGrams Iodine Grams Iodine
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What color is gram negative stain and gram positive stain if you forget to apply iodine?
If iodine is not applied, both the gram-positive and gram-negative stains will appear to be gram-negative. The iodine acts as a mordant that helps to fix the crystal violet stain in the gram-positive bacteria, making them appear purple. Without iodine, the crystal violet stain can be easily washed out of both gram-positive and gram-negative bacteria, resulting in a pink or red color.
Why is decolorization necessary when performing a gram stain?
During the procedures of a gram stain, decolorization is necessary to remove any stain or color from the gram negative cells. When a dye is used to stain gram positive cells, both gram positive and gram negative cells retain color. Mordant is used to bind the original stain to gram positive cells so when decolorizer is used they retain color. After the mordant has been used a decolorizer is used to wash away colo in gram negative cells. Counterstains are used to stain gram negative cells to better visualize contrasting cells. An example of a decolorizer that works well is ethanol.
What is the mordant reagent for?
to fix the color of the stain
What is determined of the Gram Stain?
A gram stain is a cow
Can a Gram stain a prion?
Protists are often stained using a silver stain, not a Gram stain.
What is the use of Iodine in gram stains?
The iodine in the gram stain serves as a mordant or fixative.
Why is gram's iodine called mordant?
Gram's iodine is called a mordant because it fixes the primary stain to the cell wall and adds any color.
Why gram's iodine called a mordant?
Gram's iodine is called a mordant because it fixes the primary stain to the cell wall and adds any color.
What is the appearance of gram negative bacteria after addition of mordant in the gram stain?
Red/pink
WHAT ARE the different reagents in gram stain method and its uses?
Mordant is the reagent used in the gram stain method. By using this type of reagent bacteria are more easily seen. It is important to a doctor to know what kind of bacteria is present so that he knows what to prescribe to a patient to get rid of the bacteria.
What is the function of iodine solution in the gram stain?
It allows the primary stain crystal violet to remain in the cell instead of being washed out. Due to the larger size of the crystal violet molecule, when the ethanol is applied (the decolorizer) the stain will not be washed out of the Gram (+) positive cells.
Is mordant used in acid fast stain?
The heat is the mordant for an acid-fast stain
What mordant is used in spore staining?
Heat is the mordant used in the spore stain, it fixes the primary stain.
What color is gram negative stain and gram positive stain if you forget to apply iodine?
If iodine is not applied, both the gram-positive and gram-negative stains will appear to be gram-negative. The iodine acts as a mordant that helps to fix the crystal violet stain in the gram-positive bacteria, making them appear purple. Without iodine, the crystal violet stain can be easily washed out of both gram-positive and gram-negative bacteria, resulting in a pink or red color.
Why is decolorization necessary when performing a gram stain?
During the procedures of a gram stain, decolorization is necessary to remove any stain or color from the gram negative cells. When a dye is used to stain gram positive cells, both gram positive and gram negative cells retain color. Mordant is used to bind the original stain to gram positive cells so when decolorizer is used they retain color. After the mordant has been used a decolorizer is used to wash away colo in gram negative cells. Counterstains are used to stain gram negative cells to better visualize contrasting cells. An example of a decolorizer that works well is ethanol.
What is the mordant reagent for?
to fix the color of the stain
What is the difference between Jensen's version ang hucker's modification in gram staining based on reagents and gram reaction to fungi?
What is modified in Jensen's modification of Gram stain? Jensen's modification: This method involves use to methyl violet as primary stain, iodine and potassium iodide in water as mordant, absolute alcohol as decolorizer and neutral red as counterstain
