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The most critical step of gram staining is the decolorization step as crystal violet stain will be removed from both G+ve & G-ve cells if the decolorizing agent(e.g alchohol ) is left on too long.
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What is the most common stain?
Gram staining
What are some of the best laundry stain removers?
The best stain remover depends on the type of stain and the type of material you use. The safest stain remover is water, but if you have a protein stain hot water will make the stain worse. Most people agree that bleach is the strongest stain remover, but unless the garment is white or color-safe bleach will cause a worse stain.
Which stain is most difficult to remove?
Red Wine
Methylene blue can be prepared as a basic stain or an acidic stain. How would the pH affect the staining of bacteria?
# The pH will determine if the bacteria will have a particular charge. If the chromophore is a positive ion like the methylene blue in the equation shown in the reading, the stain is considered a basic stain; if it is a negative ion, it is an acidic stain. Most bacteria are stained when a basic stain permeates the cell wall and adheres by weak ionic bonds to the negative charges of the bacterial cell.
What system is most crucial for calcium?
skeletal!!
Which step is most crucial or most likely to cause poor results in the gram stain?
Gram staining is a type of differential staining in which two types of bacteria are differentiated on the basis of their cell wall either gram positive or gram negative although all the steps in gram staining are crucial, the most important step the most crucial step in the performance of the Gram staining procedure is the decolorization step which is the Acid-Alcohol (3% HCl and 95% Ethanol) and must be timed correctly; the crystal violet stain will be removed from both Gram-positive and negative cells if the decolorizing agent is left on too long (a matter of seconds).
What is the purpose of staining an unknown organism?
By doing differential stains on an unknown organism, you can learn more about that organism. One of the most helpful stains would be the Gram stain. The gram stain will differentiate from Gram positive and Gram negative cells, narrowing your bacteria down a lot. Other stains include: Acid-Fast stain, Capsule stain, Endospore stain, and PHB stain.
Why is decolorizing the most crucial step?
It is possible to decolourise gram positive bacteria and thus get false results of all gram negative organisms. Similarly, it is possible to under-decolourise and get all gram positive organisms. Ideally controls of known organisms should be run with each 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.
What are the uses of the gram stain technique scientifically speaking?
Gram stains are used to analyze bacteria and determine their characteristics. The most popular use of a gram stain is to determine the thickness of a cell wall in bacteria.
What is the most common stain?
Gram staining
What is the stain most useful in clinicians to decide for bacterial infection?
Methylene blue a basic stain is generally used to identify the external morphology of bacteria.The other stain which is used as differential stain and which can also differentiate the baceteia on the basis of their cell wall is gram stain i.e. Crystal voilet and is counter stained with Saffranine
Which part of bacteria cell is most involved in gram stain?
The cell wall.. gram stain tests for presence of a thick outer layer of peptidoglycan.
Which Gran Positive or negative which is more serious?
Gram positive bacteria responds to the Gram stain; gram negative bacteria does not. The two bacteria do not respond to the same antibiotics. Right now the most dangerous bacteria is a gram negative bacteria. That could change.
Why would gram negative bacteria appear purple after gram stain?
The simple staining procedure makes to visualize bacteria clearly, but it does not distinguish between organisms of similar morphology. The Gram staining method is named after the Danish bacteriologist (1882) Hans Christian Gram, is one of the most important staining techniques in microbiology. It is almost always the first test performed for the identification of bacteria. The primary stain of the Gram's method is crystal violet. Crystal violet is sometimes substituted with methylene blue, which is equally effective. The microorganisms that retain the crystal violet-iodine complex appear purple brown under microscopic examination. These microorganisms that are stained by the Gram's method are commonly classified as Gram-positive or Gram non-negative. Others that are not stained by crystal violet are referred to as Gram negative, and appear red. In this method the fixed bacterial smear is subjected to the following staining reagents in the order of sequence listed below Primary stain Crystal violet is used first and stains all cell purple = Mordant = Grams iodine serves as a mordant, a substance that increases the cell affinity for a stain. It does this by binding to the primary stain thus forming an insoluble complex. The resultant crystal violet iodine complex serves to identify the color of the stain. At this point all cells will appear purple black. = Decolorizing agent = Gram staining is based on the ability of bacteria cell wall to retaining the crystal violet dye during solvent treatment. The cell walls for Gram-positive microorganisms have a higher peptidoglycan and lower lipid content than gram-negative bacteria In Gram-negative cells, subsequent treatment with a decolorizer, (95% ethyl alcohol) dissolves the lipid layer from the gram-negative cells. The removal of the lipid layer enhances the leaching of the primary stain from the cells into the surrounding solvent. In contrast, the solvent dehydrates the thicker Gram-positive cell walls, closing the pores as the cell wall shrinks during dehydration. As a result, the diffusion of the violet-iodine complex is blocked, and the bacteria remain stained. Counter stain A counterstain of basic fuchsin or saffranin is applied to the smear to give decolorized gram-negative bacteria a pink color. Since only gram-negative cells undergo decolorization they may now absorb the counter stain. Gram-positive cell retain the purple color of the primary stain. Basic fuchsin stains many Gram-negative bacteria more intensely than does safranin, making them easier to see. Some bacteria which are poorly stained by safranin, such as Haemophilus spp., Legionella spp., and some anaerobic bacteria, are readily stained by basic fuchsin, but not safranin. The polychromatic nature of the gram stain enables determination of the size and shape of both Gram-negative and Gram-positive bacteria. If desired, the slides can be permanently mounted and preserved for record keeping.
If you stain a wet mount of living cells with iodine what are you most likely to see under a microscope?
Starches and (maybe) Gram-positive bacteria.
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.
