Q: If an unknown bacteria was given that was gram-positive coccus, and the catalase test was performed,…
A: Gram-positive bacteria, such as Staphylococcus aureus, are bacteria that provide a positive response…
Q: Why is CFU more applicable to a culture of streptococcus than to a culture of E.coli
A: Streptococcus is a Gram-positive bacteria that are spherical in shape. This bacteria is responsible…
Q: Why do cells need to be kept in the freezing devices first then transferred to liquid nitrogen…
A: Rapid freezing of cells can cause ice crystals large crystals can be formed in which cells are…
Q: Why is it important to keep the culture at the correct incubation temperature when measuring the…
A: Generation time is the time which is taken by the bacteria to double in number during a specified…
Q: Why does a streaking method used to inoculate plates result in isolated colonies?
A: Streaking method is used to obtain pure colonies of microbes(bacteria) from a proper single species…
Q: What is agar and why is it necessary for growing bacteria on plates?
A: Agar is a mixture of two polysaccharides- agarose and agaropectin. It is derived from red-purple…
Q: What is the correct shape of the unknown bacterium growing on your MacConkey agar?
A: Macconkey Agar This agar includes bile salts, which are found in the gut. Bile salts help in…
Q: to observe the motility of an UNKNOWN Bacteria isolated from a mixed culture, which technique/s is…
A: Motility is the ability of an organism to move from one place to other, generally, the bacteria…
Q: Do we have to do an antibiotic sensitivity test to ensure the result? and what is the type and name…
A: Antibiotic Sensitivity Test: Antibiotic sensitivity testing, often known as antibiotic…
Q: How can the enrichment culture technique be used medically?
A: Bacteria require appropriate environmental conditions for its growth. Solid or a liquid preparation…
Q: What concentration of agar is used in a semisolid medium for motility determination?
A: Motility is a feature characteristic of only some bacteria. This ability allows the bacteria to move…
Q: Why are semi-solid media such as TTC deeps suitable to test motility of bacteria?
A: There are several parameters which need to be studied in microbiology about different…
Q: Why is glucose not the choice of carbohydrate for most differential media used in the identification…
A: Bacilli present in the intestinal tract are rod shaped bacteria.for example, enteric bacteria…
Q: Is the Triple-Sugar Iron Agar (TSIA) a complex or defined medium? Explain based on its composition.…
A: A growth medium is a also known as a culture medium which can be solid, liquid, and even…
Q: When is sterilization by filtration preferred over sterilization by heat? Why? What makes heat an…
A: Answer :- 1)Filteration is the sterilization process wherein there is the physical removal of…
Q: If SIM medium was used for motility determination for Proteus vulgaris, what noticeable change to…
A: What is motility? Motility is the ability of an organism to move by itself. Eucaryotic cells use…
Q: Why should culture media after inoculation be incubated at an optimal temperature immediately?
A: Culture media, also called as growth media, are particular combinations of nutrients and other…
Q: What are the differences between bacteriostatic and bacte-ricidal disinfectants?
A: Bacteriostatic refers to the property of preventing the growth of the bacteria, while the…
Q: what is the culture media for gram-positive bacteria?
A: The culture media for gram positive bacteria is Mannitol salt agar . The presence of bile salts, as…
Q: What is the importance of using a test/control organism in describing the cultural characteristics…
A: The food materials on which the organism is developed is called culture medium and the development…
Q: How can a suspect bacterium be fingerprinted?
A: DNA fingerprinting is a technique for detecting a high number of minisatellites in the genome at the…
Q: Explain why it is important to use only a small amount of bacteria when preparing a smear
A:
Q: If the five-digit code that is tabulated cannot be found in the EnteroPluri-Test Codebook, what that…
A: Prokaryotes are the primitive organisms that were the first to develop and harness life on Earth.…
Q: Why are smears of capsulated bacteria not heat-fixed before staining as opposed to Gram staining?
A: Gram staining is a differential staining technique developed by Danish bateriologist Hans Christian…
Q: What would be the expected outcome of an endospore stain test If the bacteria is a pathogenic…
A: Endospore stain is a differential stain that is used to image endospores in bacteria. A few genera…
Q: what is sterilization or define sterilization?
A: Sterilization is defined as the process where all the living microorganisms, including bacterial…
Q: Can culture media be sterilized in the hot air oven? why or why not?
A: Sterilization is the process of deactivating, killing, or removing any kind of microorganism (or…
Q: Why is 15 minutes generally used for sterilization? Why is agar added to medium?
A: Sterilization is the process in which all life forms like microbes (fungi, bacteria, viruses,…
Q: How can moist heat sterilization can sterilize antibiotic solution?
A: Moist heat sterilization is a technique that uses heated, increased pressure steam to sterilize an…
Q: How does the agar dilution method differ from streaking toobtain isolated colonies?
A: Both these are methods to culture microorganisms and have their respective pro and cons as mentioned…
Q: Agar is a complex polysaccharide obtained from seaweed and cannot be digested by most…
A: Growth media is the nutrients rich medium that helps in the growth of several bacteria and other…
Q: Once the completed test establishes the presence of coliforms in the water sample, why might you…
A: Water is tasteless, transparent, inorganic. Colorless, and odorless chemical substance. Its chemical…
Q: What are the culture media that can be used for cultivating non-specific and specific…
A: A microbiological culture medium is a substance that promotes the growth, support, and survival of…
Q: what is your initial assumption of the organism causing this disease
A: Bacteria are the prokaryotic microorganism and based on the structural cell walls, Gram stain…
Q: Explain why culture based biochemical and genetic testing would not be the ideal method to identify…
A: Microbial culture or microbiological culture is a technique in microbiology in which microorganisms…
Q: What microbe requires serum components to be added to the growth medium?
A: Introduction Microorganisms:- An organism that can be seen only through a microscope, They live in…
Q: selective agar media for gram-positive bacteria?
A: Phenyl Ethyl Alcohol Blood Agar is a selective media for gram positive bacteria.
Q: Why is egg enrichment not added to BPA prior to sterilization?
A: Baird–parker agar or BPA is a selective medium is identify or isolate S. aureus in food. It contains…
Q: If testing had come back as oxidase negative, urease positive and growth on MacConkey agar, what…
A: MacConkey agar is a selective and differential culture medium used for the isolation and…
Q: If the seven-digit profile that is tabulated cannot be found in the API® 20E Analytical Profile…
A: The API® 20E System, is a biochemical panel for identifying and differentiating members of the…
Q: Why are plated media stored in an inverted position?
A: Plated media enables the isolation of microorganisms from samples or specimens.
Q: Describe how you would make 10 ml of a 1:500 dilution of bacteria by performing TWO SEPARATE…
A: A serial dilution is the stepwise dilution of a substance in solution. Normally the dilution factor…
Q: What would happen if the enrichment method in the isolation of bacteriophage was omitted?the…
A: The bacteriophages are bacteria that are infected by a virus are known to exist in all possible…
Q: What method can be used to achieve sterilization?
A: It is required to describe the method to be used to achieve sterilization.
Q: What might have been some of the culture conditions used to isolate A. fumarolicum?
A: A.fumarolicum is an Extremophile. They are acidophilic, thermophilic and methanotropic in nature…
Q: Based on the bacterial cultivation, what are the possible organisms under its gram reaction?
A: Gram reaction in microbiology is a staining procedure that is used to differentiate bacteria based…
Q: What type of reaction or lab test differentiates the presence of either staphylococcus bacteria or…
A: Staphylococcus Bacteria which grows in cluster are Gram-positive (catalase-positive). Streptococcus…
Q: What is the goal of isolation streak plate technique? Why is microbial considered a pure culture?
A: Streaking : Streaking for isolation on an agar plate involves the successive dilution of organisms…
a) explain in your own words how to do a nitrate reduction test to identify unknown bacteria
b) explain in your own words how to perform a phenol red broth (prb) test to help identify unknown bacteria
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- In the preparation of a bacterial smear, why is there a need to fix the bacteria to the slide? Aside from passing the slide over a flame, what are the other ways of fixing the bacteria to the slide?what is the purpose of using oil immersion with the 100x objective lens? a)To prevent refraction of light b)To prevent scratching the slide c)To allow microbes to resuspend in the fluid d)Oil is not used with the 100x, but rather 40x e)To prevent microbes from dryingreview the case scenario uploaded in the photo. in your own words: a) write a hypothesis for identifying this unknown bacteria, the suspected bacteria are e coli, pseudomonas aeruginosa, and staphylocoous aureus. b) the best option to identify is gram staining, explain in your own words the steps taken to gram stain
- Describe one error in the staining procedure that would result in a Gram-positive bacterium appearing pink.This test will differentiate between aromatic amino acids with an acitivated ring from other amino acids. a) Nihydrin Test b) Xanthoproteic Test C) solubility test d) polarimeter testKoch'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.
- 1. A plate with a final dilution factor of 107 produced 210 colonies. a) What was the original concentration in the sample? b) If you were to dilute the original sample with a dilution factor of 108, how many colonies would you count on the plate? c) If you were to dilute the original sample with a dilution factor of 106, how many colonies would you count on the plate? 2. Sally Monella found 344 bacterial colonies on one of her plates. She had prepared this plate after a serial dilution of a culture of Yersinia pestis. She had pipetted 1 ml sample of diluted Yersinia pestis from a tube with the overall dilution factor of 106 into a plate and covered it with agar. She used this plate to calculate the concentration in cells/ml of a bacterial culture. a) How many organisms were in the original culture? b) Were her results valid? Why or why not?Explain why culture based biochemical and genetic testing would not be the ideal method to identify the microbe.The statement, “In the laboratory, a sterile inoculating loop is moved across the agar surface in a culture dish, thinning a sample and isolating individuals", describes which technique?
- What is the importance of the Nitrate test? What information can we gather from this test? Please explainIn preparing a bacterial smear for staining, heat fixation is done after the smear dries up.a.) Give the purpose of heat fixation.b.) What can be observed in wet mounts or hanging-drop slides that cannot be observed in heat-fixed slides?You saw no color change in both the first step and second step of the Nitrate Reduction test. What is the result of this experiment? Also, explain what happens when an excessive amount of zinc is added in the second step of this test.