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| A false negative result is a failure of the __________. | Sensitivity. |
| A false positive result is a failure of _______________. | Specificity. |
| The failure of a tests sensitivity is a _____________. | False negative |
| The failure of a tests specificity is a _______________. | False positive. |
| The _________ of a media/test is its ability to detect how much product must be made before a (+) reaction can be detected. | Sensitivity |
| The _________ of a media/test is its ability to distinguish which reaction is taking place. | Specificity |
| Is MacConkey Agar selective or differential?/ If so, what is it selective or differential for? | Both/ Selective- for gram (-)'s, because gram (+)'s cannot grow in the presence of bile salts or crystal violet. Differential between gram (-)'s and the ability to ferment lactose or those that cannot. |
| Is the Eosin Methylene blue Agar selective or differential?/ If so, what is it selective or differential for? | Both/ Selective- for gram (-)'s, because the dyes inhibit the growth of gram (+)'s. Differential- for the ability to ferment lactose. |
| What is the purpose of the dyes in the Eosin Methylene blue agar? | To inhibit the growth of gram (+)'s and to react with vigorous lactose fermenters to produce a black color. |
| In the Eosin Methylene blue agar test, you see that one plate turned black with good growth, one was pink with good growth and one stayed blue with poor growth. What is the interpretation of the results? | The black plate had an organism that is gram (-) and fermented lactose and/or Sucrose with acid production....The pink plate had a gram (-) organism that ferments lactose with little acid production..... The blue plate is a gram (+) organism. |
| In the MacConkey agar test you see a plate with good growth and is pink/red, you see a plate with poor/no growth and a plate with good growth but is colorless., What is the interpretation of the results.? | Pink plate with good growth= Gram (-) organism that produces acid from lactose fermentation.... Poor growth plate= gram (+) organism.... Good growth (colorless) plate= A gram (-) organism that does not ferment lactose. |
| In the MacConkey agar and Eosin Methylene blue tests they are selective "against" gram _____ organisms, thus you cannot determine if the organism can ferment lactose, because it was killed by the medium. | Gram (+) |
| Is the Manitol Salt agar selective or differential? If so, what is it selective or differential for? | Both/ Selective- for Staphylococcus and some Bacillus/ Differential- for the ability to ferment Manitol. |
| What makes the medium differential in the Manitol Salt agar? What makes the medium selective? | The medium being the substrate for fermentation./ Sodium chloride because its high concentration kills most bacteria, except salt loving ones. |
| The ability to ferment Manitol makes the MSA a ________________ media. | Differential. |
| In the Manitol Salt agar test you see a plate with Poor growth, a plate with good yellow growth and a plate with good red growth, what are your interpretation of the results? | Plate with poor growth= Organism inhibited by sodium chloride and NOT Staphylococcus.... Plate with good yellow growth= Organism produces acid from manitol fermentation and is possibly Staphylococcus Aureus.... Plate with good red growth= Organism doe NOT ferment Manitol and is a Staphylococcus other than S. Aureus. |
| Phenylethyl Alcohol Agar is selective against gram _______ organisms. | (-) |
| Is Phenylethyl Alcohol Agar a selective or differential media? | Selective. |
| How is Phenylethyl Alcohol a selective agent? | It inhibits gram (-) organisms by breaking down their cell membranes and allowing un-ordinary substances inside the cell and leakage of (K), which halts or disrupts DNA synthesis. |
| In the Phenylethyl Alcohol Agar test you see a plate with Good growth and plate with Poor/No growth,. What is your interpretation of the results? | The plate with Good growth= Organism is gram (+) and not inhibited by the Phenylethyl Alcohol and is probably of the "Coccus" origin..... Poor growth= Organism is inhibited by the Phenylethyl Alcohol and probably a gram (-) organism. |
| Is the Phenol Red Broth Test a selective or differential test? | Differential |
| Describe the procedure for the Phenol Red Broth Test. | You take 4 test tubes with durham tubes in them; each of which will contain different sugars (Glucose, Lactose, Sucrose and Manitol), the 4th one is an uninoculated control for color comparison. You inoculate the tubes with the organism and put in incubator. |
| In the Phenol Red Broth test you see a tube with yellow broth and a bubble in the durham tube, you see a tube with yellow broth and no bubble in the durham tube, you see a tube with red broth and no bubble in the durham tube, and a tube with pink broth and no bubble., What are your interpretation of the results? | Yellow broth w/ bubble= The organism fermented the "sugar" and had acid and gas end products./ Yellow broth w/ no bubble= Organism fermented the "sugar" w/ acid end products but no gas produced/ Red broth w/ bubble= No fermentation of the "sugar"/ Pink broth w/ no bubble= Degradation of peptone w/ alkaline end products. |
| Phenol Red is a ___________ within the test. | pH indicator |
| In the Phenol Red Broth test, acid production from fermentation of the carbohydrate (sugar) ________ the pH below the neutral range and changes the medium _________. | Lowers/ yellow |
| In the Phenol Red Broth test, deamination of _________ amino acids produces ammonia, which ________ the pH and turns the medium ______. | Peptone/Raises/ Pink |
| Describe the process of the MR-VP test. | You aseptically inoculate the MR-VP and place in incubator to allow for growth... Then you take 2 non-sterile test tubes and place 1mL of the MR-VP into each tube.... Then in one tube you add 3 drops of Methyl Red and mix, the Red color= (+) for MR and alot of acid was produced by fermentation... You add 15 drops of VP-A into the 2nd tube and mix, then you add 5 drops of VP-B and mix, the red on top of the broth= (+) for Acetoin being made, a type of fermentation pathway. |
| Which test, tests for Mixed Acid Fermentation.? | MR (Methyl Red) |
| In the MR-VP test you see that your first tube that had Methyl red added to it is Red and your neighbors had no color change, what is your interpretation of the results?.../... Your 2nd tube also turned red, but your neighbors did not, what is the interpretation of the results? | My tube had mixed acid fermentation and my neighbors did not/ My tube had 2,3 butanediol fermentation w. acetoin produced, my neighbor had neither. |
| Describe the process of the Catalase test. | First you grab a clean slide, then aseptically add a large amount of your organism that you are testing onto to the slide. Aseptically add 1mL of Hydrogen peroxide to the bacteria on the slide. |
| In the Catalase test, you see bubbles after adding hydrogen peroxide to the bacteria. What is the interpretation of the results? | The organism is capable of producing Catalase, which converts hydrogen peroxide into water and gaseous oxygen. |
| Why is the detection of an organism to produce catalase and break down Hydrogen peroxide important? | Because it tells you whether the organism is anaerobic or aerobic., which if it produces bubbles then it is most likely aerobic. |
| Describe the process of the Oxidase test..? | Grab a non-sterile petri dish and put a piece of filter paper in it, then with a sterile "Swab" put a heave of your organism down the middle of the paper, then you cover the bacteria with the oxidase reagent and observe-- a (+) result= purple color and cytochrome c oxidase is present. |
| In the Oxidase test, you see dark blue/purple on the filter paper within 20 seconds, what is your interpretation of the results? | That the organism has cytochrome c oxidase present in the ETC. |
| The chromogenic reducing agent in the Oxidase test is _____________________. | Tetramethyl-p-phenylenediamine. |
| The enzyme present in the oxidase test is ________________. | Cytochrome c Oxidase. |
| Suppose in a Oxidase test, that an organism possesses cytochrome c oxidase and the reagent turns blue at 45 seconds..., Is the test Valid?/ Is the test a False Negative or Positive?/ Poor sensitivity or specificity? | Not Valid/ False negative/ Poor Sensitivity. |
| The purpose of the Oxidase test is to determine if the organism uses ___________ metabolism. | Oxidative. |
| What is the purpose of the nitrate reduction test? | To determine if the organism uses anaerobic respiration and utilizes Nitrate as a final electron acceptor in the ETC. |
| Nitrate _____________ is the enzyme in the Nitrate reduction test. | reductase. |
| _________________ is known as the conversion of Nitrate to Nitrogen gas (N2). | Denitrification. |
| The visual presence of gas in the durham tube in the Nitrate reduction test indiactes ________________. | Denitrification. |
| Why is gas produced in the durham tube not recognized as nitrate reduction, when the organism is a known fermenter? | Because organisms that ferment also produce gas. |
| Describe the process of the Nitrate Reduction test.. | You grab 4 nitrate broths with durham tubes in them and aseptically inoculate the medium with the organism. Place in incubator and examine later. Upon examining, if the durham tube contains gas then the test is DONE! and Nitrate was reduced all the way to nitrite (denitrification). If there is no gas bubble then, further tests need to be done. You would then add about 8 drops of each reagent- Sulfanilic acid and Naphthylamine to test for nitrate reduction to nitrite. If this is (+) then the Nitrite will form nitrous acid, which reacts with the reagents to make a red color.... If no color change is made, then the nitrate was either not reduced at all or was reduced to another nitrogenous compound. If no color change occurs, then Zinc is added and if it turns red then it is (-) for nitrate reduction, because the nitrate was not reduced. |
| In the Nitrate reduction test, you see a tube with gas in the durham tube for a known fermenter, a tube with gas in the durham tube with a Nonfermenter, a tube that turned red after the reagents were added, tube that has no color change with the addition of reagents, tube w/ no color change after zinc added, and a tube that turns red after zinc is added, What is the interpretation of the results? | Tube w/ gas from known fermenter= needs more tests because the source of gas is unknown./ Tube with gas from Nonfermenter= Denitrification took place (Nitrate reducedd all the way to N2)./ Tube that is red after reagents= Nitrate reduced to Nitrite./ Tube w/ no color change after reagents= requires zinc test./ Tube w/ no color change after zinc added= Nitrate reduction to other nitrogenous compound.,/ Tube that turns red after zinc added= No nitrate reduction= (-). (Everything else is (+)).. |
| What is the only (-) result in the Nitrate Reduction test? | Further along in the test when Zinc is added to a tube and the color turns red, indicating that Nitrate was not Reduced at all. |
| T/F.? The Citrate test is used to differentiate members of Enterobacteriaceae., all of which are __________________ organisms. | True/ Facultative anaerobes. |
| Why is the blue color an indication of a (+) test result, in the Citrate test? | Because citrate (+) bacteria produce ammonia and ammonium hydroxide, both of which alkalinize the medium and turn it blue. |
| What is the purpose of the Citrate test? | The purpose of the Citrate test is to determine if an organism can use citrate as its sole carbon source. |
| Name the enzyme that is used to transport citrate into the cell and metabolize it in the fermentative pathway. | Citrate permease. |
| Name the process in the Citrate Test... | Get a citrate agar slant and aseptically add your bacteria with a needle and not a loop, too not confuse growth with a heavy inoculum. Then you incubate it and observe. |
| In the Citrate test you see a tube with No color change and No growth, a tube with Blue and a small amount of growth, and a tube with no color change and growth, what are your interpretations of the results? | Tube w/ no color change or no growth= Citrate no utilized(-)/ Tube w/ Small blue growth= Citrate utilized (+)/ Tube with No color change and Growth= (+) Citrate utilized. |
| T/F.? Organisms that produce Phenylalanine Deaminase can be identified by their ability to remove the aine group from the amino acid Phenylalanine. | True. |
| The formation of a green color in the Phenylalanine Deaminase test indicates the presence of _____________ acid and hence the presence of Phenylalanine Deaminase. | Phenylpyruvic acid |
| Describe the process of the Phenylalanine Deaminase test. | Get Phenylalanine slants and aseptically inoculate the agar in the tube and incubate, then after incubation add Ferric chloride and observe results. Green color= Phenylalanine Deaminase is present/ No color change= Phenylalanine Deaminase is absent. |
| What reaction is taking place in the Phenylalanine Deaminase test? | The enzyme Deaminase removes the amine group from Phenylalanine, which produces phenylpyruvic acid, which then later reacts with the ferric chloride added and tursn the medium green for a (+) result. |
| The hydrolytic enzymes that are used in the Bile Esculin test are _____________ enzymes. | Intracellular |
| Is the Bile Esculin test selective or differential? | Both |
| What constitutes a (+) result in the Bile Esculin test? | The darkening of the medium, which is the reaction between esculetin and ferric citrate. |
| Describe the process of the Bile Esculin test.. | You aseptically inoculate a Bile agar plate with your bacteria and inoculate for 48 hours. |
| What does the Phenylalanine Deaminase Test, test for? And how? | Phenylalanine deaminase medium tests the ability of an organism to produce the enzyme deaminase. This enzyme removes the amine group from the amino acid phenylalanine and releases the amine group as free ammonia. As a result of this reaction, phenylpyruvic acid is also produced.,. After incubation, 10% ferric chloride is added to the media; if phenylpyruvic acid was produced, it will react with the ferric chloride and turn dark green. |
| On what test does E. Coli produce a metallic green sheen? | Eosin Methylene blue agar test. |
| What does it mean when the medium stays red when MR is added to the medium? | It means that the organism uses mixed acid fermentation and that acidic end products are present. |
| T/F.? Methyl red is a pH indicator. | True |
| What is the purpose of the VP test in the MR-VP? | The VP test detects organisms that utilize the butylene glycol pathway and produce acetoin. |
| T/F.? The MR and VP tests are particularly useful in the identification of the Enterobacteriaceae.. | True |
| Eosin Methylene blue agar inhibits the growth of gram _______ bacteria. | (+) |
| In the Phenol red Broth test, if the organism being tested is unable to ferment the certain carbohydrate, but utilizes the peptone, what is the byproduct of using the peptone and what color will it turn to?/ What if the organism ferments the certain carbohydrate, then what is the by product and color change? | Ammonia by product, which is alkaline and increases the pH, which turns the medium pink./ The by product would be acid, which lowers the pH and turns the medium yellow. |
| What is the enzyme within the Nitrate reduction test? | Nitrate reductase. |
| What are the 2 reagents used in the nitrate reduction test? | Sulfanilic acid and α-naphthylamine |
| T/F.? Sulfanilic acid and α-naphthylamine are the 2 reagents used in the Nitrate reduction test. | True |
| T/F.? In anaerobic respiration, denitrification utilizes nitrate (NO3-) as a terminal electron acceptor in the respiratory electron transport chain. | True |
| What does the Bile Esculin Test, test for? How is a (+) result determined? | Test for the ability to hydrolyze esculin. If the organism hydrolyzes the eculin, it will make esculetin, which reacts with ferric citrate and produces a dark brown color. |
| T/F.? Bile esculin agar contains oxgall (bile salts) to inhibit the growth of gram positive organisms other than enterococci and group D streptococci. | True |
| Is the Citrate test a defined or undefined media? | Defined. |
| What is the Carbon source in the Citrate test? Nitrogen source? | Carbon= Sodium Citrate/ Nitrogen= Ammonium dihydrogen phosphate. |
| T/F.? Citrate (+) bacteria Produce Ammonia and Ammonium hydroxide, which alkalinize the medium and turn it blue. | True. |
| Is the Nitrate test Differential or Selective? | Differential |
| Is the Phenol Red Broth Differential or Selective? | Differential |
| Is the MR-VP test Differential or Selective? | Differential. |
| Is the Catalase test Differential or Selective? | Differential |
| Is the Oxidase test Differential or Selective? | Differential |
| Is the Citrate test Differential or Selective? | Differential |
| Is the Phenylethyl alcohol test Differential or Selective? | Selective. |
| Is the Eosin Methylene blue agar Differential or Selective? | Both |
| Is the Phenylalanine Deaminase test Differential or Selective? | Differential |
| Is the Bile esculin test Differential or Selective? | Both |
| Describe the procedure of the Citrate Test. | Get Simmons Citrate agars and aseptically inoculate with a needle lightly and incubate. |
| Is the Citrate test a defined or undefined media? | Defined. |
| T/F.? Growth on the slant with no color change in the Citrate Test is a (+) result? | True. |
| In the Bile esculin test, a (+) result is interpreted as to be what type of organism? | Streptococcus or Enterococcus. |
| T/F.? In 1918 20 million people died from influenza? | True |
| What has helped the human race with an edge over microbes? | Sanitation and antibiotics. |
| Was the centers for disease control called in?. What virus did they find? | Yes/ Hantivirus. |
| Were the navajo people plagued by the hantivirus before? | Yes |
| How does Hantivirus infect the human body and what is the reaction from the body to the disease? | It infects the cells that lines the blood vessels of the lungs and white blood cells emit cytokines that inactivate the virus, but also weaken the blood vessels. This allows the leakage of plasma into the lungs and fills the lungs with fluid, not allowing for oxygen. |
| T/F.? The el nino caused more brush and more food for mice and more mice which increased the contact of mice with humans. | True |
| What disease was seen as the same as the Hantivirus? | The English sweating syndrome. |
| Where did the new strand of Hantivirus come up? And what was new about the disease? | Argentina/ Person to person transmition. |
| What has increased our chances of coming in contact with more viruses. | War, famine, climate change and forcing adaption by effecting our environment. |
