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Carbolfuchsin can be used as a simple stain and as a negative stain as a simple stain the PH would be what?
lol, we must be in the same class, b/c i have all of the same questions.
did u figure out the answer?
I think its a base ... qc the microbiology lab
Cute, from the best that I could find some sources say pH 7 and others had given a pH 8. But could not find a solid answer.
As a simple stain it would have to have a pH of <7. As we know, the charge on the cell is always going to be negative (an anion). In order to achieve a simple stain we want the stain attracted to the cell wall; therefore, the stain must be positively charged (a cation) for the opposite forces to attract. The more acidic the compound - the smaller its pH number with 7 being neutral. As we know, the [H]+ increases as the pH decreases becoming evermore positively charged.
Simple answer: <7
What else can I help you with?
Why is the gram stain technique more valuable than the simple stain technique in the diagnostic laboratory Under what circumstances might the simple stain be preferable to the gram stain technique?
There are two types of stains, the simple stain and the differential stain. A simple stain colors all objects the same while a differential stain is used to spot differences in microorganisms. A gram stain is a differential stain, which is used to tell the difference in gram negative and gram positive bacteria. A simple stain would stain all the organisms the same and this difference would not be noted. You would be able to determine their shape, whether it is a cocci or bacillus (rod), but not the type. I'm not sure why the simple stain would be preferable unless you just wanted a quick answer as to the shape of the bacteria. In some cases, a wet prep can be made of a presumptive gram positive cocci to tell the difference between bacteria or yeast. Otherwise, I would say that the gram stain is the only way to go.
How could you differentiate between e coli and staph epidermidis using a simple stain?
E.coli is a gram negative rod mostly isolated from urine while staph is a gram positive cocci. You can differentiate them by color. E. Coli is Pink which is negative while Staph is Purple with is positive.
Explain why crystal violet would not be useful in the negative stain technique?
Negative staining techniques are designed to stain everything BUT the bacterial cells. This allows us to see the cells unstained and helps us observe their morphology (how the cells are shaped and how they group together). The cells have an overall negative charge on their surface, so they naturally attract positive charges. Crystal Violet carries a positive charge, so it would adhere to the surfaces of the cells thus staining the cells (which is not what you want in a negative stain!)
What color are gram-negative organisms if you over-decolorized them?
If the Gram Stain is completed properly, gram positive should stain purple; however, if you over decolorize a gram positive organism, the organism will appear appear pink, which is a gram negative reaction. To summarize, if you over decolorize a gram positive organism it will show as a gram negative organism.
Describe the microscopic appearance of encapsulated streptococcus if stained with safranin?
Safranin (red) is used in gram staining and endospore staining as the secondary stain. Nigrosin is used in negative staining, staining only the background and not the bacteria. Therefore, the bacteria within the capsule would stain red from the safranin. (Like in endospore staining and negative gram staining, safranin would stain the bacteria red.) Nigrosin would stain the background of the organism just as it would in negative staining. Bacteria (within capsul): stained safranin red Capsule (outer layer of bacteria): clear Background of organism: stained dark with Nigrosin
Why is the gram stain technique more valuable than the simple stain technique in the diagnostic laboratory Under what circumstances might the simple stain be preferable to the gram stain technique?
There are two types of stains, the simple stain and the differential stain. A simple stain colors all objects the same while a differential stain is used to spot differences in microorganisms. A gram stain is a differential stain, which is used to tell the difference in gram negative and gram positive bacteria. A simple stain would stain all the organisms the same and this difference would not be noted. You would be able to determine their shape, whether it is a cocci or bacillus (rod), but not the type. I'm not sure why the simple stain would be preferable unless you just wanted a quick answer as to the shape of the bacteria. In some cases, a wet prep can be made of a presumptive gram positive cocci to tell the difference between bacteria or yeast. Otherwise, I would say that the gram stain is the only way to go.
What is the value of simple stain?
A simple stain like iodine can make cell parts show up that would otherwise be nearly invisible since they are colorless.A simple stain like iodine will reveal a cell's morphology.
How would an endospore stain of e coli appear?
Negative cocci red
Would an electric motor run in reverse if wired positive to negative and negative to positive?
A simple one would.
What type of organism would you look for in a Gram stain of the blood or cerebrospinal fluid in a menin gococcal case?
In a Gram stain of blood or cerebrospinal fluid in a meningococcal case, you would look for Gram-negative diplococci, which are indicative of Neisseria meningitidis. These bacteria are the causative agent of meningococcal disease. Their appearance in the Gram stain can help diagnose the infection.
Would methylene blue stain be substituted for safranin as the counter stain in this procedure?
Methylene blue is a stain used in microbiology. The dye attaches to the object, which allows what would normally be fairly see-through to be visible to the microscope.
How could you differentiate between e coli and staph epidermidis using a simple stain?
E.coli is a gram negative rod mostly isolated from urine while staph is a gram positive cocci. You can differentiate them by color. E. Coli is Pink which is negative while Staph is Purple with is positive.
Explain why crystal violet would not be useful in the negative stain technique?
Negative staining techniques are designed to stain everything BUT the bacterial cells. This allows us to see the cells unstained and helps us observe their morphology (how the cells are shaped and how they group together). The cells have an overall negative charge on their surface, so they naturally attract positive charges. Crystal Violet carries a positive charge, so it would adhere to the surfaces of the cells thus staining the cells (which is not what you want in a negative stain!)
If Congo red is used instead of safranin in the gram stain technique what would happen?
Using Congo red instead of safranin in the Gram stain technique would not provide accurate results. Safranin is essential for counterstaining gram-negative bacteria, whereas Congo red would not differentiate between gram-positive and gram-negative cells due to its staining properties. This would lead to incorrect classification of bacteria in the Gram stain.
In a gram stain if alcohol is left out what color would a Gram-negative bacterium turn out?
If alcohol is left out during a Gram stain procedure, a Gram-negative bacterium would appear purple after the addition of the counterstain (safranin). This is because the alcohol step is necessary to remove the crystal violet-iodine complex in Gram-positive bacteria, but without it, the purple color remains in both Gram-negative and Gram-positive bacteria.
Methylene blue can be prepared as a basic stain or an acidic stain. How would the pH affect the staining of bacteria?
When methylene blue is prepared as a basic stain, it will have a positive charge and selectively bind to negatively charged components of bacterial cells, such as nucleic acids, enhancing the staining of bacteria. On the other hand, if prepared as an acidic stain, it will have a negative charge and repel bacterial cells, resulting in poor staining of bacteria.
If iodine step was amitted how would gram negative cells appear?
Iodine work as modrant to crystal violet if the iodine step will be emitted then the crystal violet will not be able to show its effect and all cells will appear pink when counter stain with saffranin
