What was the concentration of bacteria (CFU/mL) in the original suspensions used for dilutions and plating below:  Dilution Amount plated # of colonies counted 10-4 1.0 mL 271 10-5 0.1 mL 36 10-6 1.0 mL 9

Design a serial dilution of a 25-gram cheese sample to achieve a final dilution of 10-5 using 90 ml blanks. Show how you would plate out 102 through to 10-6

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Helping tags: Biology, bacterial count, dilution, serial dilution WILL UPVOTE, just pls help me answer the following questions and explain them clearly. Pls show complete solutions also for the computation part. Thank you. 1. A bacterial culture was grown for 9 hours. At 3-hour interval, the culture was sampled to determine the population of the culture, by transferring 25 ml of the suspension to 225 ml 0.85% NaCl. Three consecutive dilutions were further made by using 1 ml aliquot in 9 ml of 0.85% NaCI. One ml from each dilution was plated in each of duplicate plates. The following table shows the results of the plating method. Sampling COUNTS 2nd dilution 3rd dilution 4th dilution 0,0 30: 35 250;245 1st dilution 1st 2nd 3rd 0; 0 240; 235 TNTC 55; 60 5; 6 TNTC TNCT TNTC TNTC a) Illustrate the dilution series used and label the final dilution of each dilution. b) Determine the bacterial count (CFU/ml) every 3 hours of incubation for 9 hours. Show all computations.

An immersion lens was used to examine the microorganisms microscopically in a light microscope. ANSWER THE QUESTIONS 1. What symbols can be used to identify an immersion lens? What is the immersion system? 3. Why is it necessary to use an immersion lens to study microorganisms? 2.

The following is result from a standard plate count. What is the cell density of the undiluted culture? Please follow all SPC rules. (TNTC: too numerous to count)

Refer to the following diagram: 100 ul 100 uL 100 pl 100 µL 100 pl 100 pL 100 pl Volume to transfer A B C D E F G 900 uL in each tube 10 102 10 10 10 10 10 Dilutions E.CoN culture Volume of the diluted sample plated 100 ul 100 μL 100 pL 100 ul Volume of the 10 ml 10 ml original sample plated 10 ml 10 ml Plate D Plate E Plate F Plate G Given that Plate D has too many colonies to count, and Plate G has no colonies at all as a result of serial dilution, draw out all four plates and demonstrate what they might look like (assuming serial dilution has been performed correctly). Based on your drawings, identify the number of CFU/ml for Plate E and Plate F. Show your calculations.

You counted 4, 6, 12, 3 cells in each of the 4.outed squares of a hemacytomeyer. What are the cells per milliliter in that culture? If you resuspended your cell pellet 2.5 mL, what is the total cell count? How many uL do you need to add to a new culture if you want 4250 cells?

If you plated 0.1mL of a 103 dilution and you obtained 235 colonies on your agar plate, how many CFUs per mL were in your original sample? If a bacterium can divide once an hour, then after 5 hours, 1 bacterium will have yielded ______ bacteria