please help!!!
Posted: Fri Jul 15, 2022 5:18 pm
please help!!!
Be sure to have read the introduction for part 1 as well as Procedure 12.1 beginning on page 172. Read through the introduction and procedure for the analysis of part 1 beginning on page 179. Transfer the information from the data table below into the table in the "Results and Observations" section on page 180. Observe the image of a plate with a final dilution of 10−7 on the next page. Count the number of plaques (remember each clear area is one plaque) on the plate and enter this number in the "Number of plaques" column for the 10−7 plate in your table. Using Figure 12.3 on page 179 as a guide, complete the PFU/mL calculation for this 10−7 plate and enter your result, in proper scientific notation, in the table. After recording all data for part 1 answer question 1 at the bottom of page 180.
While each student group set up one portion of this exercise, all groups should make observations on each procedure of exercise 12 . Part 1: Parasitism Introduction In parasitism one organism, termed a parasite, is living at the expense of its host. In this association the host is often damaged or can even be killed while the parasite thrives. One way to visualize this relationship is to observe the interactions between a virus and its host cell. Bacteria infected with a bacteriophage will lyse upon release of the bacteriophage at the end of the lytic cycle. When all bacteria in the area of the bacteriophage lyse, a plaque, or clear area, will form in the agar plate. Here you will observe these plaques as an example of parasitism. Your group will continue by counting the plaques in each plate and calculating the number of plaque forming units (PFU) per milliliter of the original virus suspension. How to calculate plaque forming units (PFU) per milliiter of sample. PFU counted × difution factor ×1 volume of sample plated 1 EXAMPLE 30 plaques are present on a plate where the stock culture was diluted to 10−3 and 1 mL was plated. 30×10−31×1 mL1 10−3×1 mL30=3.0×104PFU/mL Figure 12.3: Calculating PFU/mL of sample.
Procedure NorE Statisticalian a countable plate woukl contain between 30−300 plaques. Too many or too few plaques will result in inaccurate reporting. To estimate if the plaques are in this range, divide: the plate into equal fourths and count one fourth. Uf the number of plaques in that quadrant are more than 7 but fewer than 75 it should be counted. 1. For each plate, macroscopically observe the plates for the presence of plaques, Count the number of plaques on each countable plate and record the results in the table below, Use Figure 12.1 to fill in the columns "Volume of sample plated" and "Final dilution" in the table below. 2. Calculate the number of PFU/mL. 3. Dispose of the plates by placing them in the blohazard bin. Question 1. Explain how we know a parasitic relationship is present when visualizing the plaques present on the plates in this exercise.
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While each student group set up one portion of this exercise, all groups should make observations on each procedure of exercise 12 . Part 1: Parasitism Introduction In parasitism one organism, termed a parasite, is living at the expense of its host. In this association the host is often damaged or can even be killed while the parasite thrives. One way to visualize this relationship is to observe the interactions between a virus and its host cell. Bacteria infected with a bacteriophage will lyse upon release of the bacteriophage at the end of the lytic cycle. When all bacteria in the area of the bacteriophage lyse, a plaque, or clear area, will form in the agar plate. Here you will observe these plaques as an example of parasitism. Your group will continue by counting the plaques in each plate and calculating the number of plaque forming units (PFU) per milliliter of the original virus suspension. How to calculate plaque forming units (PFU) per milliiter of sample. PFU counted × difution factor ×1 volume of sample plated 1 EXAMPLE 30 plaques are present on a plate where the stock culture was diluted to 10−3 and 1 mL was plated. 30×10−31×1 mL1 10−3×1 mL30=3.0×104PFU/mL Figure 12.3: Calculating PFU/mL of sample.
Procedure NorE Statisticalian a countable plate woukl contain between 30−300 plaques. Too many or too few plaques will result in inaccurate reporting. To estimate if the plaques are in this range, divide: the plate into equal fourths and count one fourth. Uf the number of plaques in that quadrant are more than 7 but fewer than 75 it should be counted. 1. For each plate, macroscopically observe the plates for the presence of plaques, Count the number of plaques on each countable plate and record the results in the table below, Use Figure 12.1 to fill in the columns "Volume of sample plated" and "Final dilution" in the table below. 2. Calculate the number of PFU/mL. 3. Dispose of the plates by placing them in the blohazard bin. Question 1. Explain how we know a parasitic relationship is present when visualizing the plaques present on the plates in this exercise.