what is the general rule of gram staining?
442218
Crystal Violet \nIodine Solution  \nEthanol\nSafranin \nWater \n\nGram -ve = pink\nGram +ve = purple
686566
Regular micro-grade agar is generally clear (if it's made up right), not brown.  The human mouth is incredibly dirty so if nothing grew it is probably too cold.  Needs warmth and maybe a bit of moisture.  Give it a couple of days in a warm place (not in the sun) and SOMETHING should grow!
967315
say u are going to perform a test for anion A in some sample. but you know that this test may also have a positive result with other anions B and C. \n\nyou then have to take into consideration that B and C might give you false positives as u test for A. if the background of the sample suggests it may contain B and C then find a way to remove these without affecting A.\n\nthen test for A using your originally proposed method.\n\n\nnow for the example:\nyou are to test for chloride ions. the reagent that comes to mind is aq silver nitrate which will result in white ppt of AgCl. then you realise that a ppt will form with any halide ion such as Br- and I-. you also know that AgBr and AgI solids will dissolve in ammonia while AgCl will not. so you first add ammonia to the sample, then test with silver nitrate. voila, now if a ppt forms, you will know it is AgCl only, and of course the conclusion that Cl- was present.
123104
go to http://biospectrumindia.com/content/BSTOP20/10601115.asp
887954
Sonication is hard with gram positives. The heat required often destroys the thing you are trying to extract.\n\nIt is going to have to be strong and you are best testing the equipment and probes you have to get the best answer. Try using dilution plating or protein estimation assays to work out the efficacy of disruption. It will almost certainly be in the region of minutes at high powers though,
1096752
Try \nhttp://www.cipe.org/publications/fs/ert/e24/Agarwe24.htm
815455
blocked pores and bacteria.
142875
No.  Proteus vulgaris is not one of the acid fast organisms.  It'll stain just fine with Gram's stain.\n(Gram Negative rod)
257602
Species in the genus Streptococcus (formerly called diplococcus) are gram positive, and so, would meet your criteria.\n\nThis includes Streptococcus pneumoniae (a cause of lower respiratory infection pneumonia and upper respiratory infections bronchitis, laryngitis, otitis media (middle ear) and sinusitis), and Streptococcus pyogenes (a cause of rheumatic fever, scarlet fever, erysipelas, strep throat, tonsillitis, and other upper respiratory infections)
638715
Stain with ethidium bromide (careful, its a carcinogen) and photograph under uv light.\n\nMeasure the migration of the bands and those of the size reference.  Plot the migration of the size reference on semi-log paper and use the resulting curve to detemine the size of your plasmid fragments.
224406
There are many different tests you could so on a culture to determine the type of bacteria. The main tests that you could do to find out a general idea of what Genus of bacteria you have would be things like a Gram stain, Catalase test, Oxidase test, O/F Fermenation test, growing the culture on different mediums, a motility test. Once you have done these tests there are then other tests which are more specific to one group of bacteria to give you an exact type of bacteria.
741317
This link is one of the better microbiology websites that I've used.\n\nhttp://www.textbookofbacteriology.net/
839821
Checked my bacteria program on my PDA and all that came up where....neisseria gonorrhoeae, neisseria meningitidis, moraxella catarrhalis and veillonella sp. \n\nFirst off, all I recall about those organisms is that they are aerobic cocci that are gram-negative. The exception being viellonella sp. as it is an anerobe. \n\nSecondly, I only looked for those traits I just mentioned, no idea if any of these meet your other criteria. \n\nThirdly, haven't you been doing tests all semester to narrow it down? The pathogens are limited to what you have studied, so it is not as the scope is that large. Try making a list of all of the organisms you have studied, turn it into a graph with all of the traits possible from all of the various tests...start filling in the blanks and you should have no problem figuring out which organism it is. Our specimen was contaminated and I found no problem determining both the assignment and the contaiminant using this method. \n\nPerhaps it is one of the organisms I mentioned above, it's very likely if you have studied any of them in Microbiology. But if not, use the method I described above and it really is just a process of elimination. \n\nGood luck
212417
It is the wavelenghth that is most predominant in bacteria (though this is an overstatement because bacteria is composed of many molecules that exbit differnt wavelenghths) but this is to determin the absorbance so you can use it later as a standard for how many bacterial cells are in a certain fluid.
897445
usually for gram stain, if the color is blue, the organism is gram positive and if it's pink, the organism is gram negative since the cell wall structure wouldn't be able to sustain the washing; however, the result would only be valid for a short amount of time....and since the culture was left in the incubator for a longer period of time, some of the same microorganisms have lost the ability to retain the stain and therefore the color changed from intense blue to pink...the best thing to do would be to redo the gram stain and to make sure that the culture does not stay in the incubator for too long
57968
If you are trained in microbiology you can tell by eye.  Plate out the bacteria (for single colonies) onto a universal media that is suitable for your target bacteria,  ie CLED, Maconkeys, Blood, Chocolate.  Incubate until there is a growth (usually 24hrs at 37 degreees celcsius is aerobic).  Look at the plate, are the colonies uniform in appearence.\n\nIf you are using liquid culture youu could use microscopy before plating out.  Either a gram stain or a direct (wet prep). This would let you know if you had all gram positives or all gram negatives or all rods or all  cocci or a mixture.  You would still have to plate out to make sure only one colony type grows.
66474
If you refer to Gram positive (G+)and Gram negative (G-):\nThe main difference is in the thickness of the peptidoglican layer. G- has about 10 layers of PG while G+ has more then 100 layers of PG. there are many more differences like the tichoic acid in G+ and the outer membrane and periplasm in the G-