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Q: Why Do not add more than 2 drops of copper sulfate in Biuret reagent?
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Q: Briefly explain how you can determine the presence of coliform bacteria in a water sample.
A: Coliforms are a type of bacteria. These organisms are normally harmless to the species or hosts they…
Q: Why does the oxidase test have to be read quickly?
A: The Oxidase test is a biochemical test for the identification of bacteria. The test is mainly…
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A: Introduction A solid or liquid substrate that can be used to grow cells or organ explants; a medium…
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Q: how many coliform colonies would you expect to see on your 1:10 plate? Your 1:100 plate? Explain.
A: Introduction Coliform is the gram-negative, non-spore-forming and motile or non-motile bacterial…
Q: Why is CFU more applicable to a culture of streptococcus than to a culture of E.coli
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Q: If the concentration of E. coli in a broth is between 104 and 106 cells per mL, the best way…
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Q: What would be the expected out come of a Nitrate reduction test If the bacteria is a pathogenic…
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Q: Lactose fermentation
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Q: If coliforms were present on a plated sample, would you know with certainty that the coliforms are…
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Q: 1) What are all of the different colony types that can be seen on a mixed-culture streak plate? 2)…
A: Hi! Thanks for your question. As you have posted multiple questions, I am answering only the first…
Q: Assume that you are adding 300 microliters of 1% substrate solution per well in a 24-well plate. If…
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Q: How does the ONPG/MUG test allow a sample to be assayed simultaneously for the presence of both…
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Q: A bacterial organism is used to inoculate mannitol broth medium. Following incubation the broth is…
A: A nutrient growth medium is a type of solution or mixture that is designed to provide nutrients to…
Q: Why do we test water for coliforms if they are not considered pathogenic?
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Q: what type of bacteria would be used to make sauerkraut?
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Q: what is the purpose of the FeCl3 in this aspirin test?
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Q: Describe two methods to test for the enzyme urease.
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Q: Why do we use the term CFU (colony forming unit) instead of reporting bacteria per ml? Explain.
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Q: What is the relationship between dilution factors and the efficacy of antimicrobial agents in…
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Q: How would you make two-fold serial dilutions such that the last tube is a 1:32 dilution of the…
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Q: The statement, “In the laboratory, a sterile inoculating loop is moved across the agar surface in a…
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Q: can the phenol red test also be used to determine if a certain bacterium can metabolze various…
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Q: Why is it critical to be able to determine the overall number of bacteria present in a food sample?
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Q: What is the average time period for an E. coli culture to go from lag phase to death phase? Is it…
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Q: What will happen to the color of the Coomassie reagent as more protein is added?
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Q: A disk-diffusion test using E. coli gave the following results: Disinfectant Zone of…
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A:
Q: Listen ▶ Which of the following methods of microbial control is used most often with surgical…
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Q: 50 g of food is homogenized in 450 mL of water. From this, 1 mL is added to 29 mL of water, and then…
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Q: What is the purpose of PSP (Phenolsulfonpthalein) Test?
A: Please follow step 2 for detailed explanations.
Q: Is the Mueller-Hinton Agar (MHA) a complex or defined medium? Explain based on its composition. Is…
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What is the logic behind testing for E. coli to detect fecal
contamination of water?
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- Why is CFU more applicable to a culture of Streptococcus than to a culture of E. coli?A stool specimen of a patient with severe diarrhea was cultured in a series of specialized media for isolation of enteric organisms. The cultures yielded three isolates that were species of Salmonella, Shigella, and Escherichia. Explain why the Hydrogen sulfide production test would be diagnostically significant.What is the purpose of the confirmed test in an experiment designed to test for coliform bacteria?
- can the phenol red test also be used to determine if a certain bacterium can metabolze various carbohydrates?Koch's postulates include all of the following EXCEPT O 1) Isolate the organism in pure culture. The symptoms of the test animal may vary from the symptoms seen in the O 2) patient. O 3) Inoculate a test animal with the isolated organism. 4) The organism must be isolated from the test animal in pure culture. 5) The organism isolated from the test animal must match the organism isolated from the patient.What is the coliform test when is it used? What is its purpose? How does it function? What are the advantages and disadvantages of utilizing the coliform test?
- Identify the oxidase-negative, gram negative bacillus isolated from the blood cultures of a hospitalized patient with a urinary tract infection. The organism produced colorless colonies on MacConkey agar and gives the following biochemical reactions: PAD – positive H2S – positive positive Citrate – positive Ornithine positive Lysine – negative Indole - negative Urease –How does the ONPG/MUG test allow a sample to be assayed simultaneously for the presence of both total coliforms and E. coli?Why does the oxidase test must be performed from blood agar or another medium without a fermentable sugar as MacConkey agar?
- If the concentration of E. coli in a broth is between 104 and 106 cells per mL, the best way determine the precise number of living cells in the sample, would be toa) use a counting chamber.b) plate out an appropriate dilution of the sample on nutrient agar.c) determine cell number by using a spectrophotometer.d) Any of these three methods would be satisfactory.e) None of these three methods would be satisfactory.Why is CFU more applicable to a culture of streptococcus than to a culture of E.coliProvide the conditions (e.g., intrinsic properties, storage conditions, etc.) that will make the recovery of the following microorganisms in commercially sterile foods acceptable: a) Obligate thermophilic sporeforming bacteria b) Acid-tolerant microorganisms c) Mesophilic or thermophilic sporeformers