10-1Name: ___________________________Section: __________Enumeration Lab ReportPurpose:(Why was this experiment performed?)This experiment is performed to determine the number of cells, usually by finding out the cell concentration or cell density.Materials: (Reagents, organisms, etc)Escherichia ColiMethods: (Protocol)1. 1.0 mL is pipetted aseptically into the 10^-1 tube. The dilution tube is vortexed.2. 1 mL is transferred to the 10^-2 tube and then vortexed. This continues through all of the tubes up to 10^-8. 3. 0.1 mL from each dilution tubes and the original sample are transferred to agar plates. 4. Spin the plate on the spinner while spreading the sample thoroughly throughout the plate.5. Plates are incubated at 30 degrees C for 24-48 hours6. After incubation the colonies are countedResults: DilutionfactorCFUBench 1platesCalculatedOCD*CFUBench 2plates CalculatedOCD*CFUBench 3platesCalculatedOCD*10-1TFTC10-2TFTC10-3TFTC10-4TFTC10-5TFTC10-610-710-8TFTCMean OCD*- - -* OCD = original cell densityName: ___________________________Section: __________Discussion: (What do the results indicate about serial dilutions?) This method allows bacteria to grow on the surface. Although dilution is made to reduce the sample size for ease in enumeration, sometimes the growth of microorganisms is very fast until there are too many visible colonies. Since the margin of error is dependent on the sample size, which means the larger sample size, the smaller the error would
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