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Bacterial Morphology
The bacteria are prokaryotic organisms that are single-celled, and are found to exist as free-living and possess a microscopic size. The morphology is found to vary in the bacteria, where some of them are identified as individual organisms and the others are detected as colonies. The size and shape of the bacterial cell also represent its morphology.
Bacterial cell structure
Bacteria are single-celled, tiny creatures that may enter healthy tissues and grow rapidly. Bacteria are microscopic organisms that are tiny and unicellular. These are members of the prokaryote kingdom. They live in water, air, soil, and all-natural environments. They are used in industrial and therapeutic processes, and they support a wide range of plant and animal life. The first organism to appear on the planet. Bacteria-like creatures are the oldest known fossils. Bacteria can consume a wide range of organic and inorganic elements, and some may even survive in harsh conditions.
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- How would you produce a 10^-1 dilution if a 3 mL bacterial sample using the entire 3 mL volume? suppose your professor handed you a test tube with 2.0 mL of an E. coli broth culture in it and told you to make a 10^-1 dilution of the entire culture. Explain how you would do this. Show your calculations.You perform the Methyl-Red(MR)& Voges-Proskauer(VP)test and gather the followingresults: (Uploaded picture). VP test result is on the left, MR test result is on the right. A) Please interpret these results. B) Your fellow researcher and yourself are sure your bacterial sample is either E. coli or P. vulargis. Basedupon the work we have done in lab which methods will help you determine which bacteria it is? Please explain why, the results you would want to observe and provide analysis of those results.You are testing a river water sample. Your "original" plate shows 100 coliform colonies. Assuming you did the serial dilution correctly, how many coliform colonies would you expect to see on your 1:10 plate? Your 1:100 plate? Explain.
- Design a serial dilution procedure to achieve a 56-colony count, from a sample with 8.75x105 CFU/mL bacterial concentration.One ml of a sample was added to 99 ml of buffer. 100 µ of this was plated in nutrient agar. After incubation, 247 colonies were present on the plate. How many colony-forming units were present per ml of the original sample? Show your working out. What would you record in your workbook if there were 378 colonies present? Why? B. Give definitions of these bacterial growth in relation to O2 availability. 1. E. coli , micrococcus Letues, clostridium sprogenesUsing the clinical question --"Does antibacterial foam decrease bacteria count on hands as much as hand washing with soap and water.” Question 1) Describe your study design and sample. 2) Will your findings be generalizable? Why or why not? 3) How does this exercise inform your interpretation of published research?.
- 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?The following data were obtained by incubating gram-positive bacteria in nutrient medium + disinfectant for 24 hours, then transferring one loopful to nutrient medium (subculturing). (+ = growth; - = no growth. a. Table 7.3, which disinfectant is the most effective at stopping bacterial growth? How can you tell? b. In Table 7.3, which disinfectant was bactericidal? How can you tell? c. In Table 7.3, which disinfectant was most effective against Salmonella? How can you tell? [Hint: look up Salmonella] Table 7.3 K.O. Subculture Doom Dilution Initial Subculture Initial 1:16 1:32 1:64 1:128 Mortum Sterl Dilution Initial Subculture Initial Subculture 1:16 1:32 1:64 1:128Per the USDA, whole, unpasteurized fresh eggs can contain no more than 50,000 CFU/mL bacteria in a standard plate count. You are curious if the fresh eggs that you buy from your neighbor are considered safe to consume so you use your eScience Microbiology kit to test these eggs using direct plate count after serial dilution. After you complete the experiment, you obtain 74 countable colonies from the 10-2 dilution plate. The inoculum volume you plated was 0.1 mL. How many bacteria are present in 1 mL of the egg you sampled? Are these eggs considered safe to consume per USDA standards?
- You've been tasked with observing the motility of an UNKNOWN Bacteria isolated from a mixed culture. Which technique(s) is/are the BEST to utilize? How will the procedure be carried out? Explain.Using your fingers, you are asked to aseptically touch the surface of a sterile agar plate. Illustrate the possible result from this step if your fingers are (a) unwashed – touched various things prior to placing on agar surface, and (b) washed with soap or disinfected with 70% alcohol. Describe the relative abundance of microbial growth observed on the plates. List and draw the possible characteristics of an isolated bacterial colony that can be observed based on type of (a) margin, (b) elevation, (c) texture, and (d) optical property.) If you counted 500 CFU’s in the petri dish for number 6 and 5000 CFU’s in petri dish for number 7, what would be the most justifiable explanation for this? 19) If the original sample’s concentration was 12 bacterial cells, what do you expect the count to be?