3. Were you able to distinguish between G+ cells and G- cells? Give the gram reactions of E. coli and S. saprophyticus. 4. Why is the acetone/alcohol step the most critical step in the process? 5. If you observed bacteria from a single colony that were gram variable, a. What other characteristics could you use to help you identify the organism? b. How might the age of the culture affect the results? 6. What would happen if you Gram stained E. coli, but forgot the decolorizing step? 7. What would happen if you Gram stained S. saprophyticus and forgot the decolorizing step?

3. Were you able to distinguish between G+ cells and G- cells? Give the gram reactions of E. coli and S. saprophyticus. 4. Why is the acetone/alcohol step the most critical step in the process? 5. If you observed bacteria from a single colony that were gram variable, a. What other characteristics could you use to help you identify the organism? b. How might the age of the culture affect the results? 6. What would happen if you Gram stained E. coli, but forgot the decolorizing step? 7. What would happen if you Gram stained S. saprophyticus and forgot the decolorizing step?

Comprehensive Medical Assisting: Administrative and Clinical Competencies (MindTap Course List)

6th Edition

ISBN:9781305964792

Author:Wilburta Q. Lindh, Carol D. Tamparo, Barbara M. Dahl, Julie Morris, Cindy Correa

Publisher:Wilburta Q. Lindh, Carol D. Tamparo, Barbara M. Dahl, Julie Morris, Cindy Correa

Chapter42: Basic Microbiology

Section: Chapter Questions

Problem 4CR

See similar textbooks

Similar questions

1) would you describe the contents of the soil-inoculated broth as being a “pure culture”? Why or why not? 2) How did the uninoculated broth differ in appearance from the broths inoculated with E. Coli and M. Luteus? And then how could you tell if a supposedly sterile, uninoculated broth was contaminated? Please explain in detail and highlight the important parts cuz I am confused and need help! Thanks
1) based on the difference in appearance between mixed culture streak plates and broth culture plates, what would lead you to believe that you have created a pure culture when you inoculated the broths? 2) when using the loop dilution technique to produce pour plates, did all the plates produce isolated colonies? If your goal was to ultimately create pure cultures of E. coli, M. luteus, and S. morcescens, which plate or which dilution would you use, and why would you use this plate? 3) What are the advantages and disadvantages of streak plating compared with pour plating?
1.What advantage(s) does the pour plate method have over the streak-plate method? 2.Why is the loop flamed before it is placed in a culture tube? Why is it flamed after completing the inoculation? 3.Before inoculating and pouring molten nutrient agar into a plate, why must the agar first be cooled to 50° C? 4.Explain why plates should be inverted during incubation. 5.Explain why plates should be inverted during incubation.
1.why is gram stain considered a differential stain? 2.How do gram positive and gram negative bacteria differ in cellular structure, and how does this contribute to their differential staining properties? 3.How does the age of a culture affect the gram stain reaction? What is an optimum culture age for a valid gram reaction? 4.Which step in the gram stain procedure is most prone to error?If done correctly how might that step affect the end result? 5.what is the function of mordant, and which reagent serves this purpose in the gram stain procedure? 6.List the reagents of the gram star technique in order and their general role in the staining process. 7.In what type of cell, gram -positive or gram-negative , would you find lipopolysaccharide in its cell wall?
1. How is UV radiation a good type of control mechanism against microbial growth? Please explain what happens to the microbe and effects this control causes. 2. Suppose you do the Kirby-Bauer test on a hypothetical Staphylococcus species with penicillin and tetracycline. You record diameters of 20mm for tetracycline and 24mm for penicillin. Which antibiotic is most effective against this bacterium and why? Please explain and interpret these results. 3. Please provide the scientific name of your microbe that was used in the UV experiment (i.e. S. aureus). Compare your plates and interpret/analyze your results. Please discuss your findings and any patterns you were able to gather. 4. After performing the “Effects of Antiseptics & Disinfectants” lab which agent(s) showed potential to control S. marcescens growth? P. aeruginosa? Please explain why you believe these agent(s) work. 5. What purpose does water serve in the “Effects of Antiseptics & Disinfectants” lab? What did you…
1. Why is heating the inoculating loop so important in microbiology?2. Why is it that moist heat is chosen to be the most commonly used in sterilization? 3. What part of the flame is the best part to use to sterilize an inoculating loop or needle?
2. A mannitol-salt agar plate was inoculated with these bacteria and is shown below. A. What type of organisms grow on this medium? B. Based on the reaction below, what can you say about the organism derived from the patient's abscess?
2.How do gram positive and gram negative bacteria differ in cellular structure, and how does this contribute to their differential staining properties? 3.How does the age of a culture affect the gram stain reaction? What is an optimum culture age for a valid gram reaction? 4.Which step in the gram stain procedure is most prone to error?If done correctly how might that step affect the end result? 5.what is the function of mordant, and which reagent serves this purpose in the gram stain procedure? 6.List the reagents of the gram star technique in order and their general role in the staining process. 7.In what type of cell, gram -positive or gram-negative , would you find lipopolysaccharide in its cell wall?
1.What would happen if an error occurs in a serial dilution? 2.Why does one cell not necessarily mean equal to one colony? 3. What would happen if incubation time of inoculated agar plates is too short or too long? 4.Why is viable plate count so convenient to apply when counting bacteria?
1 (a)Why is the spectrophotometer set at 0.000 absorbance for the uninoculated tube of broth? (B) Why can't you use the same plot (or standard curve) of plot of absorbance versus cell count for Escherichia coli for other bacteria? (C)List 3 advantages of estimating microbial numbers or biomass by the turbidimetric method? (C)(ii)List 2 disadvantages of this method? (D) Can you measure all kinds of microbes this way? Why not? ( this is not a graded assignment)
1. You were given a mixed nutrient agar broth culture of bacteria. a. How will you determine the different types of bacteria present in the mixed culture? b. How will you make a pure culture of these bacteria in a slant nutrient agar? c. How will you identify these bacteria?
1. How is UV radiation a good type of control mechanism against microbial growth? Please explain what happens to the microbe and effects this control causes. 2. Suppose you do the Kirby-Bauer test on a hypothetical Staphylococcus species with penicillin and tetracycline. You record diameters of 20mm for tetracycline and 24mm for penicillin. Which antibiotic is most effective against this bacterium and why? Please explain and interpret these results.