Microbiology: An Introduction
11th Edition
ISBN: 9780321733603
Author: Gerard J. Tortora, Berdell R. Funke, Christine L. Case
Publisher: Benjamin Cummings
expand_more
expand_more
format_list_bulleted
Textbook Question
Chapter 6, Problem 3CAE
The number of bacteria in saliva samples was determined by collecting the saliva, making serial dilutions, and inoculating nutrient agar by the pour plate method. The plates were incubated aerobically for 48 hours at 37°C.
Bacteria per ml Saliva | ||
Before UsingMouthwash | After UsingMouthwash | |
Mouthwash 1 | 13.1 × 106 | 10.9 × 106 |
Mouthwash 2 | 11.7 × 106 | 14.2 × 105 |
Mouthwash 3 | 9.3 × 105 | 7.7 × 105 |
What can you conclude from these data? Did all the bacteria present in each saliva sample grow?
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solutionStudents have asked these similar questions
The number of bacteria in saliva samples was determined by collecting the saliva, making serial dilutions, and inoculating nutrient agar by the pour plate method. The plates were inoculated aerobically for 48 hours at 37°C.
What can you conclude from this data? Why?
Mouthwash
CFU per ml in salvia
Before Use After Use
Listerine
2.22 x 107 1.22x107
Schmidts Mouthwash
2.42 x 107 3.22x105
Biotene Mouthwash
3.21 x 107 2.12 x106
Mary wanted to know the amount of microbes in her garden. To do this, she took a 10g soil
sample, added urea, and then let it incubate for one week. She then performed serial dilution a
shown below:
10 g soil sample
To:
1ml
90 ml
Dilution Bottle
1 ml
9 ml
Tube 1
0.1 ml
0.45 ml
111
9.9 ml
Tube 3
9 ml
Tube 2
9.55 ml
Tube 4
Calculate the dilution of the bottle and each tube. Be sure to show complete solutions and box
your final answer.
You are testing unpasteurized milk for the presence of bacterial contamination. Starting from the undiluted milk, you do serial dilutions, and plate 0.5 ml of 4th dilution on agar. If you counted 78 CFUs from the 4th plate, how many bacteria/ml do you expect? (show solution)
Do you think standard plate counts are very accurate? Why or why not?
Chapter 6 Solutions
Microbiology: An Introduction
Ch. 6 - Prob. 1RCh. 6 - Prob. 2RCh. 6 - Prob. 3RCh. 6 - Seven methods of measuring microbial growth were...Ch. 6 - By deep-freezing, bacteria can be stored without...Ch. 6 - A pastry chef accidentally inoculated a cream pie...Ch. 6 - Nitrogen and phosphorus added to beaches following...Ch. 6 - Differentiate complex and chemically defined...Ch. 6 - DRAW IT Draw the following growth curves for E....Ch. 6 - NAME IT A prokaryotic cell hitched a ride to Earth...
Ch. 6 - Two culture media were inoculated with four...Ch. 6 - Two culture media were inoculated with four...Ch. 6 - Use the following graph to answer questions 3 and...Ch. 6 - Use the following graph to answer questions 3 and...Ch. 6 - Assume you inoculated 100 facultatively anaerobic...Ch. 6 - The term trace elements refers to a. the elements...Ch. 6 - Which one of the following temperatures would most...Ch. 6 - Which of the following is not a characteristic of...Ch. 6 - Which of the following types of media would not be...Ch. 6 - An organism that has peroxidase and superoxide...Ch. 6 - E. coli was incubated with aeration in a nutrient...Ch. 6 - Clostridium and Streptococcus are both...Ch. 6 - Most laboratory media contain a fermentable...Ch. 6 - Flask A contains yeast cells in glucose-minimal...Ch. 6 - Clinical Applications and Evaluation 1. Assume...Ch. 6 - Heat lamps are commonly used to maintain foods at...Ch. 6 - The number of bacteria in saliva samples was...
Additional Science Textbook Solutions
Find more solutions based on key concepts
How does trandlation differ from transcription?
Microbiology: Principles and Explorations
Describe the evolution of mammals, tracing their synapsid lineage from early amniote ancestors to true mammals....
Loose Leaf For Integrated Principles Of Zoology
How does the removal of hydrogen atoms from nutrient molecules result in a loss of energy from the nutrient mol...
Seeley's Anatomy & Physiology
11. In the early 1800s, French naturalist Jean Baptiste Lamarck suggested that the best explanation for the rel...
Campbell Biology: Concepts & Connections (8th Edition)
The pedigrees indicated here were obtained with three unrelated families whose members express the same disease...
Genetics: From Genes to Genomes
Knowledge Booster
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, biology and related others by exploring similar questions and additional content below.Similar questions
- Below is an MSA plate inoculated with bacteria and grown at 37*C for 2 days. Be pecific and thorough in your answers for parts a and b below. The color of the plate is yellow because b) The presence of bacterial colonies indicates that the bacteria can survivearrow_forwardLook for two product of Milk in the internet and answer the following queston: 1. Method of sterilization used. 2. What is the Bacterial culture and flavor used if there is any. 3. What is the Fat, Protein & Carbohydrate(sugar) content? 4. Is fortification done? What substances has been fortified (based on the label)? 5. Are Vitamins & amino acids added? Name them based on the label.arrow_forwardA student needed to transfer bacteria from a broth culture to an agar plate. Below is the step-by-step what was done to accomplish this. The transfer of bacteria was not successful because of which step? 1. Cap of the broth culture is removed 2. The mouth of the bottle is flamed 3. The loop was flamed 4. The loop was inserted into the culture to pick up the bacteria 5. The loop was flamed 6. The loop containing the bacteria was used to introduced to spread the agar plate 7. The plate was placed in an incubator at 30 Celciusarrow_forward
- S aureus Styphimurium S aureus S typhimurium Nutrient Agar Plates MacConkey Agar Plates S epidermidis Unknown S epidermidis Unknown S aureus S typhimurium S aureus S typhimurium Mannitol Salt Agar Plates Gram Stain S epidermidis Unknown S epidermidis Unknownarrow_forwardwhich agent was most effective against the spore-forming bacteria that was tested? How does the agent kill bacterial cells?arrow_forwardLook for Alaska Milk in the internet and answer the following queston: 1. Method of sterilization used. 2. What is the Bacterial culture and flavor used if there is any. 3. What is the Fat, Protein & Carbohydrate(sugar) content? 4. Is fortification done? What substances has been fortified (based on the label)? 5. Are Vitamins & amino acids added? Name them based on the label.arrow_forward
- which agent was most effective against the fecal coliform that was tested? how does this agent kill bacterial cells?arrow_forwardFirst There Was One, Then There Were Two RESULTS Results of the plate counts for the samples you worked with. Number of Colonies for Each Dilution Plated Time Sampled 10-3 10-4 10-5 10-6 10-7 10-8 10-9 10:40 TNTC TNTC TNTC 280 TFTC TFTC3 T FIC2 TFTC TFTC 13 TNTC TNTU TNTC TNTC I60 TNTC TNTC 1:00 TFTC q a TFTC O 1:20 11:40 12:00 TNTC TNTC87 TFTC TFTC, TFICg TNTC ITNTC ITNTC TNTC 125 TNTC TNTC TNTC TNTC 164 TFIC 13 T+TC Calculate the cfu/ml for each time sample you worked with in the space below and record those values in the table below.arrow_forwardBased on the graph below, write a discussion in detailarrow_forward
- Serial dilution is recommended prior to pour and spread plate. Why is this so?arrow_forwardPrepare 50 plates of Sheep's Blood Agar using 100mm petri dish. Add 10% of blood to the media. (Manufacturer's instructions: Suspend 38 g of blood agar base dehydrated powder in 1 liter of distilled or deionized water.) Pour 25 mL of prepared medium per plate. Express answer to the nearest whole number. How many grams of the dehydrated powder should be weighed? Answer: What is the volume of distilled water that should be used in the preparation? Answer: What is the volume of sheep's blood that should be added to the sterilized and cooled blood agar base? Answer:arrow_forwardA food sample with an unknown number of contaminating bacteria was serially diluted to 10-6. A volume of 0.1 mL (100 μL) of the dilutions was plated. The 10-6 plate contained 96 colonies. What was the original microbial concentration?arrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
Serology 101: Testing for IgG and IgM antibodies; Author: Beckman Coulter Dx;https://www.youtube.com/watch?v=LtqKB-qpJrs;License: Standard youtube license