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iodine act as a mordant..on the gram positive bacteria which got really thick and abundence of peptidoglycan layer, the crystal violet will fix to the peptidoglycan layer..meanwhile in gram negative bacteria which is lack of peptidoglycan layer, the alcohol or acetone will wash it away
What else can I help you with?
What is the importance of iodine after primary stain?
Iodine is used after the primary stain in the Gram stain procedure to form a complex with the crystal violet dye, which helps to stabilize the dye within the bacterial cell wall. This step enhances the retention of the primary stain in Gram-positive bacteria.
What is crystal violet iodine complex?
Crystal violet iodine complex is a chemical compound formed when crystal violet dye interacts with iodine. This complex is commonly used in microbiology as a stain for bacterial cells, allowing them to be visualized under a microscope. The crystal violet iodine complex binds to the peptidoglycan layer of bacterial cell walls, imparting a purple color to the cells.
Diff between gram's iodine and iodine?
iodine& grams iodine Gram's iodine is a solution of 2% iodine and 3% potassium iodide in 70% ethanol. Gram's iodine is also used as a forensic toxicology reagent for the detection of alkaloids, as a source of iodine for iodometric titrations, as an indicator for the presence of starch, and as a general laboratory source of iodine/iodide. This solution is laboratory grade, and not for medicinal use. Iodine is non metallic,dark gray,lustrous,solid element
What does lugol's iodine stain do to the activity of the cell?
I just did a lab in biology called "How Plant and Animal Cells Differ" and in the packet it had that question. The answer is: Lugol's iodine stain stops the activity of the cell. It kills whatever specimen it is staining.
Differences between lugols iodine and grams iodine?
Lugol's Iodine = 20g Potassium Iodide + 10g Iodine dissolved in 1L H2O Gram's Iodine = 6.7g potassium iodide + 3.3g Iodine dissolved in 1L H2O Recipe's taken from Flinn Scientific Catalog I have on campus. Looks to me as Gram's is just a dilute version of Lugol's. Same ratio of KI:I just less of it. Couldn't tell you much about differences in application however.
What function of iodine in gram stain?
fixing the stain so that the first dye which is the crystal violet will not be washed away during rinse process.
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.
Is iodine a basic stain?
No, iodine is not a basic stain. Iodine is commonly used in Gram staining to identify bacteria as either Gram-positive or Gram-negative based on their cell wall composition. It acts as a mordant in the staining process and helps to fix the crystal violet stain in Gram staining.
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.
Why do you use iodine to stain a cell?
Iodine is used to stain cells because it binds to glycogen and starch, making them more visible under a microscope. This helps to visualize the cellular structures and identify specific components within the cell.
What is the difference between lugols iodine and grams iodine?
Lugol's iodine is a mixture of elemental iodine and potassium iodide, commonly used as a disinfectant and as a supplement to support thyroid function. Gram's iodine, on the other hand, is a stain used in microbiology to differentiate between gram-positive and gram-negative bacteria based on their cell wall composition. The main difference lies in their applications and compositions.
What is the action of iodine in grams stain?
Iodine is used to bind the Crystal Violet to the Gram Positive microbes.
What function of lugol's iodine in gram staining?
fixing the stain so that the first dye which is the crystal violet will not be washed away during rinse process.
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 secondary stain in gram stain procedure?
It is crystal violet & stains all cells purple.
What is the importance of iodine after primary stain?
Iodine is used after the primary stain in the Gram stain procedure to form a complex with the crystal violet dye, which helps to stabilize the dye within the bacterial cell wall. This step enhances the retention of the primary stain in Gram-positive bacteria.
What is the mordant in a gram stain?
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.
