What would likely happen if you plated undiluted bacteria culture onto a plate The colonies would be too close to count The BLANK Standard When creating a serial dilution for the standard plate count method, BLANK Water When using the standard plate count method to enumerate bacteria in a sample, it is important to perform a serial BLANK Dilution Chose the correct examples of when it is important to determine the number of bacteria in a sample Determining the quality of milk Assessing the purity of food or water Testing to see if a patient has a bladder infection You decide to make a plate counting experiment.What would happen if you plated undiluted bacteria culture directly on the plate The colonies would be too close for counting Statistically reliable plates have no fewer than BLANK 30 When determining the number of bacteria in a sample, the dilution factor needs to be multiplied by what amount The amount of bacterial colonies on a plate Counting 67 colonies on a plate with 1ml of the 1:1,000,000 dilution indicates that BLANK 6.7x10-7 What actions are necessary to establish if a patient has a bladder infection Measure the number of bacteria in the urine Why is it necessary to dilute a culture when plating bacteria for a counting experiment To achieve a density that allow the individual colonies to be distinguished during counting What is the minimum number of colonies that must be present for a plate to be considered statistically valid 30 If 141 colonies are counted on a plate that received 0.1ml of the 1:1,000,000 dilution, how many bacteria were present in 1.0ml of the undiluted culture To calculate multiply the number of colonies by the dilution factor 1.4 x 10-9 You want to compare the bacterial density in 3 different water sources.After 24h, the plates contain 500, 750, and 270 colonies respectively.
Microbiology Serial Dilution Examples Serial Dilution ForWhat do you do Repeat the experiment by plating a series of dilutions of each sample Which of the following are situations where the standard plate count could result in an underestimate of bacterial numbers You inoculate and incubate the plates in anaerobic conditions You accidentally use a selective medium instead of a general-purpose medium for plating the dilutions You forget to put the plates into the incubator after plating What are the advantages of using a colony counter when conducting a standard plate count It has grid lines to help you keep track of which colonies have already been counted It has a magnifying glass that can be used to locate and count smaller colonies It automatically adds to the colony count each time you press on the glass Why is it necessary to dilute a sample in order to determine bacterial numbers The bacterial density in the original sample may be too high for the formation and counting of isolated colonies What is the advantage of using the standard plate count over the enumeration methods when determining the safety of a food or water sample It provides a count of only living bacteria which represent the safety concern TRUE OR FALSE: Is it necessary to use a colony counter when completing a standard plate count. ![]() S. aureus will likely show BLANK Different Bacterial cultures need to be placed into BLANK Cuvettes Place these steps in order for reading the absorbance of two bacterial samples Let the spectrophotometer warm up for 15 min. Set the wavelength to 550nm Calibrate the machine by inserting a cuvette with sterile medium and pressing reset button. Remove cuvette and pour the sterile broth into the waste beaker Insert a clean cuvette with bacterial sample into the spectrophotometer and read the absorbance in the digital display Remove cuvette, pour bacterial sample into waste beaker, and rinse with water and repeat absorbance reading steps with a second sample Absorbance or optical density is measured using a BLANK Spectrophotometer The amount of light absorbed is BLANK Directly proportional Measuring absorbance in the indirect spectrophotometer method can allow one to determine if cells are BLANK Growing The growth curve of bacteria shows a steep increase during the BLANK Exponential Most bacteria have different BLANK Growth After using an uninoculated nutrient broth to blank the spectrophotometer, the blank must be removed and a cuvette with bacterial culture added. The cover is closed, and the BLANK Absorbance Correctly order the following steps for calibration of a spectrophotometer Turn on and allow to warm up for 15 minutes Set the wavelength to 550nm Insert a cuvette of sterile nutrient broth into the sample holder Close the cover of the sample holder Adjust the absorbance to 0 by hitting the reset button What will be the correct procedure for transferring bacteria To use a new clean pipette each time you sample from a different bacterial culture Why is it important to rinse the cuvette with water If the cuvette is not rinsed, there will be remains from the previous sample that would affect the following absorbance reading When studying population growth curves with a spectrophotometer, why is it unlikely that you will see the typical steep decrease of the curve during the death phase The spectrophotometer measures turbidity of the tube, which is influenced by both living and dead cells What phase of a typical curve is not usually seen when conducting density measurements with a spectrophotometer Death phase THIS SET IS OFTEN IN FOLDERS WITH. ![]() Question: MICROBIOLOGY, Serial Dilution Problemsoecifically Confused About What To Do With The 1g Of Soil In The 5mL Of Water When Back Tracking. Please Helpalso Im Used To CFUs Being Given Per Plate So Im Not Sure Where To Beginthis Is As Far As I Got And Im Not Sure If Its Correct Even. Tube 1, Dilution factor 100 mL1mL 102 This is 10-2 dilution of original dilution. Tube 2, Dilution factor 10 mL1mL 10 This is 10-1 dilution of tube 1. Microbiology Serial Dilution Examples Full Answer PreviousTube 3, Dilution factor 10 view the full answer Previous question Next question Transcribed Image Text from this Question A student in Biology 328 performed a serial dilution series on his dirt sample to determine the starting concentration of bacterial cells. He performed 5 dilutions by adding 1 mL of the previous culture to the next culture (sterile water) and plated the last dilution as follows: 1 mL I mL I mL 1 mL 1 mL PLATE A: 1 mL 5 ml.s (1 gram dirt) 99 mLs 9 mLs 9 mLs 9 mLs 9 mLs PLATE B: 0.1 mL 19 1omL ImL 10mL 1OmL 10mL 100mL Im omL He plated the bacteria by pipetting 1 mL and 0.1 mL (Plates A and B respectively) and spreading the culture evenly over a R2A plate. Please answer the questions on the following page regarding this dilution series. Questions: 1. What is the dilution factor for each dilution (Added amounttotal amount dilution factor) 2. What is the TOTAL dilution factor for Plate A What makes the total dilution factor for Plate B different from Plate A (Total dilution factor individual dilution factors multiplied by each other) 3. After the plates were incubated at 30C for 24 hrs, 273 colonies formed on plate A and 30 colonies formed on plate B. What is the concentration, in c.f.u.mL, of the original diluted dirt sample 4. As shown, the student has 5 mLs of the original culture. How many c.f.ug dirt are there in the sample 5. Say the student changed dilution 5; adding 1 mL of the previous culture to 4 mLs of sterile PBS. A. How does this change the dilution factor of dilution 5 B. What would be the new original dirt sample concentration, in c.f.u.g dirt, if Plate A and Plate B yielded the same amount of colonies as indicated in question 3 Please attach and show all work to receive full credit. Questions: 1. What is the dilution factor for each dilution (Added amounttotal amount dilution factor) A) TOm T 2) TOm 3tom 4) tom 5) 10mL. What is the TOTAL dilution factor for Plate A What makes the total dilution factor for Plate B different from Plate A (Total dilution factor individual dilution factors multiplied by each other) 100mL 3. What is the concentration, in c.f.u.mL, of the original diluted dirt sample 27330 303151.5 (avq CFUs) x 10x 1OXIO K IOx (O X 100- 15 15000000 1.515x 10 4. Say the student changed dilution 5; adding 1 mL of the previous culture to 4 mLs of sterile PBS A.
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