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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.
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What are the gram reaction of mycobacterium?
Whar are the gram reaction of mycobacterium?Type your answer here...
What relationship did you find if any between the Gram-staining reaction of a microorganism and its susceptibility to antiseptics and disinfectants?
Gram + bacteria has thick cell walls. This feature makes them more resistant to antiseptic and disinfectants.
If your organisms were all blue with pink spots what is the Gram reaction if your organisms were all pink but had some blue spots what is the Gram reaction?
Gram positive cells take up the crystal violet, which is then fixed in the cell with the iodine mordant. This forms a crystal-violet iodine complex which remains in the cell even after decolorizing. It is thought that this happens because the cell walls of gram positive organisms include a thick layer of protein-sugar complexes called peptidoglycans. This layer makes up 60-90% of the gram positive cell wall. Decolorizing the cell causes this thick cell wall to dehydrate and shrink, which closes the pores in the cell wall and prevents the stain from exiting the cell. At the end of the gram staining procedure, gram positive cells will be stained a purplish-blue color. Gram negative cells also take up crystal violet, and the iodine forms a crystal violet-iodine complex in the cells as it did in the gram positive cells. However, the cell walls of gram negative organisms do not retain this complex when decolorized. Peptidoglycans are present in the cell walls of gram negative organisms, but they only comprise 10-20% of the cell wall. Gram negative cells also have an outer layer which gram positive organisms do not have; this layer is made up of lipids, polysaccharides, and proteins. Exposing gram negative cells to the decolorizer dissolves the lipids in the cell walls, which allows the crystal violet-iodine complex to leach out of the cells. This allows the cells to subsequently be stained with safranin. At the end of the gram staining procedure, gram negative cells will be stained a reddish-pink color. Remember:
The major criteria used in placing bacteria into different groups is based on differences in?
Biologists separate bacteria into two groups based on their reaction with the gram stain as Gram Positive and Gram Negative bacteria.
What is the gram reaction of Human papellomavirus?
The Gram reaction is used to classify bacteria into two broad categories, Gram positive and Gram negative. The Gram stain characteristics of a bacterium depends on its cell wall components and thickness. The viruses do not have any cell walls or other equivalent. The viruses are too small to be seen by light microscopy, only exception is the Pox virus. So the Gram stain is not appropriate for virus identification. However, if one is able to see papilloma virus through light microscope, these may appear Gram negative. Because the crystal violet dye would be removed by decolorizer, and the counterstain (safranin or carbol fuchsin) would show its color.
Is the gram reaction due to the outer membrane?
If by outer membrane you mean cell wall, then yes.
What are the gram reaction of mycobacterium?
Whar are the gram reaction of mycobacterium?Type your answer here...
What are some of the reason for a Gram variable reaction?
what are some of the reasons for a gram-variable reaction
What relationship did you find if any between the Gram-staining reaction of a microorganism and its susceptibility to antiseptics and disinfectants?
Gram + bacteria has thick cell walls. This feature makes them more resistant to antiseptic and disinfectants.
If your organisms were all blue with pink spots what is the Gram reaction if your organisms were all pink but had some blue spots what is the Gram reaction?
Gram positive cells take up the crystal violet, which is then fixed in the cell with the iodine mordant. This forms a crystal-violet iodine complex which remains in the cell even after decolorizing. It is thought that this happens because the cell walls of gram positive organisms include a thick layer of protein-sugar complexes called peptidoglycans. This layer makes up 60-90% of the gram positive cell wall. Decolorizing the cell causes this thick cell wall to dehydrate and shrink, which closes the pores in the cell wall and prevents the stain from exiting the cell. At the end of the gram staining procedure, gram positive cells will be stained a purplish-blue color. Gram negative cells also take up crystal violet, and the iodine forms a crystal violet-iodine complex in the cells as it did in the gram positive cells. However, the cell walls of gram negative organisms do not retain this complex when decolorized. Peptidoglycans are present in the cell walls of gram negative organisms, but they only comprise 10-20% of the cell wall. Gram negative cells also have an outer layer which gram positive organisms do not have; this layer is made up of lipids, polysaccharides, and proteins. Exposing gram negative cells to the decolorizer dissolves the lipids in the cell walls, which allows the crystal violet-iodine complex to leach out of the cells. This allows the cells to subsequently be stained with safranin. At the end of the gram staining procedure, gram negative cells will be stained a reddish-pink color. Remember:
The major criteria used in placing bacteria into different groups is based on differences in?
Biologists separate bacteria into two groups based on their reaction with the gram stain as Gram Positive and Gram Negative bacteria.
What gram reaction do you expect from acid-fast bacteria?
Gram positive
What describes the correct cellular morphology and gram reaction for staphylococcus aureus?
The cell morphology of Staphylococcus aureus is spherical in appearance. Spherical bacterium are known as coccus and appear as tetrads (4) or more in groups. They stain Gram +.
What is the gram reaction of Human papellomavirus?
The Gram reaction is used to classify bacteria into two broad categories, Gram positive and Gram negative. The Gram stain characteristics of a bacterium depends on its cell wall components and thickness. The viruses do not have any cell walls or other equivalent. The viruses are too small to be seen by light microscopy, only exception is the Pox virus. So the Gram stain is not appropriate for virus identification. However, if one is able to see papilloma virus through light microscope, these may appear Gram negative. Because the crystal violet dye would be removed by decolorizer, and the counterstain (safranin or carbol fuchsin) would show its color.
Is cell a countable or uncountable noun Do I say 1 gram of cell or 1 gram of cells?
The noun cell is a countable noun. You should say, "one gram of cells".
What is the gram reaction of s epidermidis?
Gram positive, coccus shape.
Are polymers gram negative?
A gram stain tests the contents of the cell wall. Polymers do not have cell walls.
