gram stain?
Q. what if there was a,mistake when performing a gram stain and there was a reversal of crystal violet and safranin stains?
Asked by sinajina - Sun Jun 29 23:42:19 2008 - - 1 Answers - 0 Comments

Supposed to perform Gram stain on a sample from a pure culture of bacteria and observed a field of red and?
Q. Supposed to perform Gram stain on a sample from a pure culture of bacteria and observed a field of red and purple cocci. Adjacent cells were not always the same color. What is the conclusion?
Asked by pia - Sat Feb 16 00:38:31 2008 - - 1 Answers - 1 Comments

A. Because you said that this is a pure culture, you can conclude that they are gram-positive cocci. That's the whole answer, and you're done here. I've included more if you're interested for real life cases where you don't know if it's a pure culture or a contaminated one. If you're not interested, skip the rest of this. ---Extra discussion of real-Life problems a purple organism is definitely a gram-positive coccus. The commonest of these are streptococcus (including pneumococcus) and staphylococcus. Gram-negative cocci are orangish-red, and include organisms like gonococcus and meningococcus. The red cocci that you sometimes see may be gram-negative cocci or poorly stained gram positives. The next two photos will illustrate the… [cont.]
Answered by Yaybob - Sat Feb 16 01:43:02 2008

Why is the counter stain for the gram stain procedure different from the counter stain used for the acid-fast?
Q. Help please Why is the counter stain for the gram stain procedure different from the counter stain used for the acid-fast stain procedure? This is the last question in need to answer on my lab report thats due tomorrow morning, help if you can! Thanks
Asked by iDriveAlude - Mon Mar 10 00:41:40 2008 - - 2 Answers - 0 Comments

A. The counter stain is different cause the main stain is different...gram stain is purple...and we don't usually counter stain it in a smear..just a tissue section would get a counter stain to help see the organism...so eosin is pink and would give good contrast TB is an acid fast organism...that won't stain with the gram stain...its also a slow grower and very small... the ZN stain is used at my work...If I remember correctly...its pink or pinky red...and so you cannot have a pink counter stain... In the Hand E stain the counter stain is the eosin..which is pink...so you would need a colour that enhanced the part which you are looking at... Actually the best one is the flourescent stains...easier to see...but I think it has a high… [cont.]
Answered by ptolomy - Mon Mar 10 00:57:36 2008

What does the Iodine mordant do in a gram stain?
Q. In a gram stain what is the purpose of the iodine mordant? Is it to trap the crystal violet in the gram positive bacteria?
Asked by bbap - Thu Feb 15 23:49:52 2007 - - 2 Answers - 0 Comments

A. By definition a mordant is a substance that set dyes. It doesn't really contribute to the coloring of the bacteria. The iodine in Gram stain fixes the crystal violet to the bacterial cell wall of the Gram positive bacteria.
Answered by Wei H - Fri Feb 16 01:40:29 2007

Why should only young cultures be used for the Gram stain?
Q. Why should only young cultures be used for the Gram stain?
Asked by on_gt - Mon Mar 19 08:40:20 2007 - - 1 Answers - 0 Comments

A. young cultures are on the rise towards peak of their population. There will be more live bacteria that have not degraded or had a chance to adjust/mutate to their environment.
Answered by catd88 - Mon Mar 19 09:43:03 2007

What are some advantages and disadvantages of using the Gram stain method. ?
Q. Also, is there a different improved method other than the Gram stain?
Asked by dcpb2k - Thu Nov 20 05:18:36 2008 - - 3 Answers - 0 Comments

A. Gram stain only differentiates between Gram-positive and Gram-negative bacteria. To be honest, it's not of much utility - the Gram-status of it isn't divided nicely (like oh, genus 1 is all gram + and genus 2 is all gram -)
Answered by Fiona F - Thu Nov 20 05:23:01 2008

Why should gram stain reaction only be determined at the oil immersion objective?
Q. Why is it that oil immersion objective is used in viewing results of gram staining?
Asked by sexiestmolecularbiologist - Sun Nov 23 10:30:25 2008 - - 2 Answers - 0 Comments

A. Because Bacteria are, for the Most Part, Small.
Answered by mdGreg C - Sun Nov 23 10:53:58 2008

a scientist performs a gram stain on a specimen. is this procedure sufficient to indentify the organism?
Q. a. no, because many organism will look the same in a gram stain. b. no, because the culture may be contaminated. c. yes, because the gram stain is often the first procedure done. d. yes, because the gram stain is often the only procedure done.
Asked by kohlirosy - Mon Dec 24 17:20:24 2007 - - 4 Answers - 0 Comments

A. I agree witht the first response of a. AJB, Ph.D.
Answered by AJ B - Mon Dec 24 17:31:59 2007

Has anyone done a gram stain before?
Q. I am taking microbiology and tried to do a gram stain 3 times, and each time I saw nothing under the microscope. I know you are supposed to use Crystal Violet, Iodine, Ethanol Alcohol, and Safranin, but how long did you leave the ethanol on. Any tips would be of help?
Asked by el cid - Tue Sep 18 09:41:38 2007 - - 1 Answers - 0 Comments

A. Problems that can arise would be not heat-fixing the smear of cells on the slide (they will wash off if not fixed to the slide), washing too vigorously or too long (just gently wash, and this just means let the wash flow over the slide, it doesn't mean scrubbing with a towel :) and wash just until the stain is not obviously coming off anymore. Also, make sure you look at the cells with the high power objective (oil immersion lens if you have that available). Here is a procedure that may help: Good luck!
Answered by N E - Tue Sep 18 10:22:26 2007

Suppose you performed a Gram stain on a sample?
Q. Suppose you performed a Gram stain on a sample from a pure culture of bacteria and observed a field of red and purple cocci. Adjacent cells were not always the same color. what do you conclude?
Asked by MZ. "G" - Mon Mar 17 23:51:10 2008 - - 3 Answers - 0 Comments

A. The cells were likely Gram positive from an old culture. Peptidoglycan does not get thicker with the age of the bacteria. And if it did, Gram + bacteria would still be purple, and Gram - bacteria would still be red/pink (the crystal violet stain is not able to penetrate the LPS/outermembrane of Gram - bacteria). If you have an older culture, some of those bacteria will be nutrient deprived. They will not have the resources to repair gaps in their peptidoglycan layers. If the peptidoglycan is not intact, crystal violet will be easily removed from Gram + cell walls during the decolorizing step of the procedure. These Gram + bacteria will then take up the counterstain (safranin), and will appear pink under the microscope. Also malidoke… [cont.]
Answered by Pheromones - Fri Mar 21 22:16:58 2008

what part of the bacterial cell in most involved with Gram stain, and why?
Q. what part of the bacterial cell in most involved with Gram stain, and why? answer email to me!!
Asked by veniesh - Fri Sep 12 21:09:02 2008 - - 3 Answers - 0 Comments

if you performed a gram stain on human cells what would happen?
Q. suppose you perform a gram stain on a sample from pure culture of bacteria and observed a field of red and purple cocci. adjacent cells were not the same color what do you conclude?
Asked by shynquiet - Fri Nov 17 20:11:18 2006 - - 3 Answers - 0 Comments

A. I would conclude that those magic mushrooms were just a bit too strong. What is a gram stain? Can you have a culture of pure bacteria? Why would human cells have bacteria? I have studied biology, but you have lost me with this question. Did not Monet paint exquisite pictures of red and purple cocci in the late spring?
Answered by gyorzxk - Fri Nov 17 20:18:57 2006

Is a gram stain considered a biochemical test?
Q. I was wondering if a gram stain was considered a biochemical test in microbiology, like for example an indole test.
Asked by Lost=( - Sun Mar 1 11:03:27 2009 - - 2 Answers - 0 Comments

A. No Gram staining is used to differentiate bacterial species into two large groups (Gram-positive and Gram-negative) based on the chemical and physical properties of their cell walls. The Gram staining is not a biochemical test since we are not looking at metabolic properties of the bacteria. Indole test is done to determine if bacteria can breakdown the amino acid tryptophan into indole.Where the metabolic properties of the bacteria is tested. Rather than the physical properties of the bacteria. A positive result indicates the ability of the bacteria to breakdown tryptopan to form indole. A negative result shows the inability of the bacteria to tryptophan to produce indole.
Answered by misha_pjk - Sun Mar 1 13:18:16 2009

gram stain can find the result for clamaydia.that is true?
Q. i have a friend she's wonder why to her vagina discharge..and she came the doctor told her to gram stain her vagina to know if she have a clamaydia..that is true to find the result for clamaydia,tru gram stain?
Asked by chatterly petter - Wed Feb 6 01:27:24 2008 - - 4 Answers - 0 Comments

A. A gram stain will show inflammatory cells which might suggest an infection by chlamydia or other bacteria, but you cannot specifically identify chlamydia as the cause of the inflammation on a gram stain alone. Chlamydia bacteria are very small - only 0.25 micron in diameter, and are usually hard to see under a light microcope. The bacteria that cause gonorrhoea, on the other hand, are about twice the diameter, and can usually be seen on a gram stain as gram negative intracellular diploccoci.
Answered by __A_YAHOO_USER__ - Wed Feb 6 04:17:13 2008

How could the gram-stain be useful in determining whether a culture is pure or not?
Q. What would you expect to see if the culture is pure and what might you see if it is not pure?
Asked by Jamie K - Wed Sep 23 13:31:57 2009 - - 1 Answers - 0 Comments

A. Pure: All gram positive or gram negative. All cells look similar Mixed: some gram positive, some gram negative. Cells look different
Answered by Tim - Wed Sep 23 13:46:28 2009

How does Gram stain work, and how is it useful to doctors treating bacterial diseases?
Q. How does Gram stain work, and how is it useful to doctors treating bacterial diseases?
Asked by candy - Fri Mar 20 12:15:18 2009 - - 2 Answers - 0 Comments

A. The Gram stain is one of the first and most important means of identifying bacteria. It works by staining the bacteria with a dye, usually crystal violet, and this stains all bacteria (whether Gram positive or Gram negative) purple. The next step is to use iodine on the bacteria for about 1 minute and this will act to fix the dye onto the bacteria. Next the slide the bacteria is one is flooded with a solution of alcohol and acetone for 10-30 seconds. What this does is all of the dye in the Gram negative cell walls have been washed away by the alcohol, acetone, or even 95% ethanol can be used. This is because the gram negative cell wall, while it does have a layer of peptidoglycan it is significantly thinner than gram positive bacteria.… [cont.]
Answered by satts8243 - Fri Mar 20 13:04:27 2009

when it is useful to perform a gram stain on a mixture?
Q. what might cause a gram variable reaction? 2. what is medical significant of a capsule? 3.what is the function of copper sulphate in this procedure??
Asked by qistina - Sat Feb 16 05:00:12 2008 - - 1 Answers - 0 Comments

A. 1. When you have bacteria and you want to visualize it under a microscope and be able to tell what sort of cell wall it has. If the culture is old, some of the cell walls will be in poor condition and lead to gram variable results. 2. Capsules make it more difficult for your immune system to recognize foreign bugs. 3. I have never used copper sulphate in a procedure before, sorry.
Answered by Pheromones - Sat Feb 16 13:07:51 2008

What happens to a Gram-negative bacterium when it's treated with Gram stain?
Q. A.It turns blue. B. It turns red. C. It swells and bursts. D. It turns purple.
Asked by Adriana M - Mon Feb 11 15:53:44 2008 - - 2 Answers - 0 Comments

A. B
Answered by Chris L - Mon Feb 11 15:57:38 2008

Why is the gram stain of both practical and theoretical importance in microbiology?
Q. Why is the gram stain of both practical and theoretical importance in microbiology?
Asked by jabin - Tue Aug 11 17:28:45 2009 - - 3 Answers - 0 Comments

What would you expect from a Gram stain done on a slide that was heated too hot during the heat-fixed smear?
Q. What would you expect from a Gram stain done on a slide that was heated too hot during the heat-fixed smear?
Asked by victim of microbio - Wed Sep 3 18:19:10 2008 - - 1 Answers - 0 Comments

A. - it will destroy the cell wall of the bacteria - a gram (+) bacteria might become gram (-) or vice versa
Answered by neewoh - Wed Sep 3 21:40:02 2008