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For Gram Stain experiment.
The gram-positive, g+, which stained purple in color (use Crystal violet) as the bacteria contain a thicker layer of peptidoglycan with no lipopolysaccharide and protein bound the outer membrane of the bacteria (bacteria A).
The gram-negative, g-, which stained in red (if the safranin (red dye/counter stain is use) appear due to the bacteria (bacteria B) which lack of peptidoglycan and it is bound by a lipopolysaccharide and protein layer.
The thicker the peptidoglycan, the more coloring agent (crystal violet ions, CV+) it can absorb. Hence, give more purple in color to the bacteria and this will be the gram-positive, g+ bacteria. On the other hands, bacteria B seem has thinner peptidoglycan thus it absorb less purple color from the CV+, and after decolourise (using alcohol) and stained with safranin (red dye), only the bacteria with lack of peptidoglycan change to red hence we can say bacteria B as gram-negative, g-.
Hence the outcome is the bacteria with thicker peptidoglycan layer be the gram-positive, g+(purple color) while the thinner peptidoglycan layer be the gram-negative, g-. (red color)
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Why would bacteria stain gram variable?
A gram-negative cell will lose its outer membrane and the peptidoglycan layer is left exposed. or it is best to use younger cells ( 12-24hr) because older gram positive bacteria are subject to break down of the cell wall by enzymes that are produced with age which may result ingram variable staining.
Is the gram stain useful for distinguishing between yeasts?
Doubtful, as yeast are fungi with walls of chitin, while bacteria have walls of peptidoglycan.
What physical part of bacteria is responsible for the color difference at the end of the gram staining process?
In Gram positive bacteria it is the cell wall made up of a thick layer of peptidoglycan which holds the stain so that this bacteria can be viewed. Gram negative bacteria have two thin layers of peptidoglycan which loses the stain in the secondary washing, hence their terminology as negative.
What is the difference between gram plus and?
Gram positive bacteria stain purple with the Gram stain. This is because of the fact that they contain a thick layer of murein in their cell wall, which takes up the stain very well. Gram negative bacteria, however, do not display the thick layer of peptidoglycan on their outer surface. Therefore, they stain red with the counter stain.
What happens if you use gram stain on a virus?
Most likely nothing. The gram stain will only stain the peptidoglycan cell wall of bacteria. Most viruses have a protein coat called a capsid. The capsid will not take up either the crystal violet or the safranin of a Gram stain.
How does thickness of peptidoglycan affect the outcome of gram stain?
For Gram Stain experiment. The gram-positive, g+, which stained purple in color (use Crystal violet) as the bacteria contain a thicker layer of peptidoglycan with no lipopolysaccharide and protein bound the outer membrane of the bacteria (bacteria A). The gram-negative, g-, which stained in red (if the safranin (red dye/counter stain is use) appear due to the bacteria (bacteria B) which lack of peptidoglycan and it is bound by a lipopolysaccharide and protein layer. The thicker the peptidoglycan, the more coloring agent (crystal violet ions, CV+) it can absorb. Hence, give more purple in color to the bacteria and this will be the gram-positive, g+ bacteria. On the other hands, bacteria B seem has thinner peptidoglycan thus it absorb less purple color from the CV+, and after decolourise (using alcohol) and stained with safranin (red dye), only the bacteria with lack of peptidoglycan change to red hence we can say bacteria B as gram-negative, g-. Hence the outcome is the bacteria with thicker peptidoglycan layer be the gram-positive, g+(purple color) while the thinner peptidoglycan layer be the gram-negative, g-. (red color)
How do you get gram positive bacilli?
You do not " get " them, but gram positive bacteria are gram positive because their cell wall is of sufficient thickness and properly constructed to hold the Gram stain. They have one thick wall of peptidoglycan that holds the stain against being washed away. Gram negative bacteria have two thinner walls which allow the stain to be washed away, basically.
What characteristic does a gram stain indicate?
The difference between gram-positive and gram-negative bacteria.
Function of iodine in Gram stain?
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 does a gram reaction of a cell refer to?
the Gram reaction is based on the structure of the bacterial cell wall. In Gram-positive bacteria, the dark purple crystal violet stain is retained by the thick layer of peptidoglycan which forms the outer layer of the cell. In Gram-negative bacteria, the thin peptidoglycan layer in the periplasm does not retain the dark stain, and the pink safranin counter stain stains the peptidoglycan layer. In other word,the gram reaction refers to how the cells reacts to the gram-staining process.
Gram-positive bacteria have a thick cell wall composed of?
Gram positive bacteria are so called because their cell walls are one thick layer of peptidoglycan, basically, so the stain is trapped in the cell wall and not rinsed away.
How do you calculate mild steel thickness from stain steel thickness?
By thick control.
Why would bacteria stain gram variable?
A gram-negative cell will lose its outer membrane and the peptidoglycan layer is left exposed. or it is best to use younger cells ( 12-24hr) because older gram positive bacteria are subject to break down of the cell wall by enzymes that are produced with age which may result ingram variable staining.
Is the gram stain useful for distinguishing between yeasts?
Doubtful, as yeast are fungi with walls of chitin, while bacteria have walls of peptidoglycan.
Which structure of bacteria is determied by gram staining?
The part of the bacterial cell that appears to play the most important role in determining whether an organism if gram-positive or not is the cell wall. it is determined by whether or not it retains the stain during testing.
What physical part of bacteria is responsible for the color difference at the end of the gram staining process?
In Gram positive bacteria it is the cell wall made up of a thick layer of peptidoglycan which holds the stain so that this bacteria can be viewed. Gram negative bacteria have two thin layers of peptidoglycan which loses the stain in the secondary washing, hence their terminology as negative.
What is the current theory about the mechanism of the gram stain?
The gram stain is a basic differential stain used to determine if a bacterial cell is gram positive or negative. Gram positive cells have a thick peptidoglycan layer that will trap the crystal violet iodine crystalls and apear purple. Gram negative cells only have a thin peptidoglycan layer that allows the crystals to diffuse out of the cell and will only be seen with the application of a counterstain, such as safranin which turns the cells pink.
