Microbiology: Principles and Explorations
9th Edition
ISBN: 9781118743164
Author: Jacquelyn G. Black, Laura J. Black
Publisher: WILEY
expand_more
expand_more
format_list_bulleted
Concept explainers
Videos
Textbook Question
Chapter 6, Problem 1CTQ
Exactly 100 bacteria with a generation time of 30 minutes are introduced into fresh sterile broth at 8:00 A.M. and maintained at an optimum incubation temperature throughout the day. How many bacteria are present at 3:00 P.M.? How many generations will take place by 5:00 P.M.?
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solution
Students have asked these similar questions
starting with four bacterial cells per milliliter in a rich nutrient medium, with a 1-hour lag phase and a 30-minute generation time, how many cells will there be in 1 ml of this culture after 10 hours?
A culture with approximately 4x105 cells/mL were incubated. After 10 hours, the number of cells had increased to 5x109.
a) How long was the generation time in minutes?b) How many generations have occurred?
There are two cultures of yeast cells in the pictures, one has been incubated for 6 hours and one has been incubated for 24 hours. After a 10x dilution by taking 100µl of each culture and adding it to 900 µl water in a microcentrifuge tube and 100µl sample from the tube was taken to view in the counting chamber.
a) Count the total number of yeast cells for each culture respectively
b) Calculate the concentration and density of yeast cells for each culture respectively
Chapter 6 Solutions
Microbiology: Principles and Explorations
Ch. 6 - What are the differences between the lag phase and...Ch. 6 - How does logarithmic rate of increase differ from...Ch. 6 - Prob. 1.3SCCh. 6 - Why does a direct microscopic count of bacteria...Ch. 6 - What does the ending -phile mean? Distinguish...Ch. 6 - What enzymes do most obligate anaerobes lack? How...Ch. 6 - Prob. 2.3SCCh. 6 - Prob. 3.1SCCh. 6 - Distinguish between the various kinds of media:...Ch. 6 - What is the purpose of a stock culture? Why is it...
Ch. 6 - Prob. 1CCSCh. 6 - Exactly 100 bacteria with a generation time of 30...Ch. 6 - In the above example, do you think that the number...Ch. 6 - Prob. 3CTQCh. 6 - Prob. 1SQCh. 6 - Match the following growth phase terms to their...Ch. 6 - Which of the following is the best definition of...Ch. 6 - Prob. 4SQCh. 6 - The most probable number (MPN) technique is a...Ch. 6 - Match the terms with their definitions:Ch. 6 - Prob. 7SQCh. 6 - Why do foods containing a high concentration of...Ch. 6 - Some bacteria have complex nutritional...Ch. 6 - Prob. 10SQCh. 6 - Which type of cell will shift to aerobic...Ch. 6 - Which of the following statements about endospores...Ch. 6 - Prob. 13SQCh. 6 - Blood agar is often used to observe changes in the...Ch. 6 - A bacterial medium that contains 20 grams of beef...Ch. 6 - MacConkey agar contains the dye, crystal violet,...Ch. 6 - Prob. 17SQCh. 6 - What are the purposes of carrying out the streak...Ch. 6 - Prob. 19SQCh. 6 - During quorum sensing, bacteria sense their...Ch. 6 - Prob. 21SQCh. 6 - Identify the position of each of the following on...
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
- You are given a 1 gram soil sample of unknown bacterial load. After doing 10-fold serial dilutions of the soil in sterile water, 100 uL volumes are taken from each dilution for preparation of pour plates. Following incubation, each half of the 10-8 plate has 46 colonies.a) What was the dilution factor?b) How many bacteria were present in the soil?2. Staphylococcus aureus divides every 20 minutes. A culture begins with 10 bacterial cells.a) After 5 hours, how many generations have occurredb) After 5 hours, how many bacteria are present?3. How many milliliters would you need to prepare a 10-2 dilution from a 10ml starting culture?arrow_forwardYou just finished plating your electroporatio products on your YPD-Zeocin plate and you think you did everything perfectly but you come back the folloeing week and have zero colonies. Which of the following could be the reason for the absence of colonies? A) You centrifuged your electroporated cells for 30 sec at 16,000 rpm instead of 4,000 rpm before plating them B) You added sorbitol+YPD to your cells thirty minutes after pulsing your cells C) The Zeocin had not been added to the plates when they were made. D) All of the above E) Both a and b onlyarrow_forwardWhat are the defining characteristics of the exponential/log phase of the bacterial growth curve. Explain the culture conditions that arise that cause the phase to end. In different culture media, and the exact same starting inoculum, will the end of exponential/log occur at the same time? Why or why not? A graph or a drawing of the growth curve would help but is not essential to answer this question.arrow_forward
- Answer the following questions briefly and concisely 1.How do bacteria in a chemostat and those in a batch culture vary from one another? 2. What happens in a chemostat if the dilution rate is higher than the organism's maximum specific growth rate? 3.Does a chemostat require the use of pure cultures? 4. Why would a complicated culture media for Leuconostoc mesenteroides be simpler to make than one with a fixed chemical composition?arrow_forwardThe solution containing bacterial spores is heated in an autoclave. When the autoclave has reached a constant temperature of 121 °C, there are still 106 spores/ml. The specific death constant for bacterial spores at 121 ° C is 11.62 min-1. How long should the heating be continued at a constant temperature so that there are 1 spores/ml left? Enter the answer in minutes to three decimal places.arrow_forwardWhat is the major difference between an enrichment culture and a selective culture? Why are microbial doubling times in nature typically longer than those obtained in the lab? Briefly describe the following mechanisms of measuring bacterial growth: Direct microscopic cell count Plate count Most probable numberarrow_forward
- Contrast the terms thermal death time and decimalreduction time. How would the presence of bacterialendospores affect either value? What time and temperature is necessary to ensure sterility in the autoclave?arrow_forwardIn the multiple fermentation tube technique does the absence of gas formation after 24 hours constitute a negative presumptive test for coliform bacteria? Explain.arrow_forwardA bacterial strain is growing exponentially. At 1:00pm the titre of the culture is 2x10^3 cells per ml. Three hours later, the culture is still growing exponentially and the titre is 4x10^4 cells per ml. How many generations have elapsed, what is the generation time, and what will the titre be at 9:00pmarrow_forward
- Why are the streak plates incubated at 7°C when selecting for psychrotrophic bacteria?arrow_forwardList 5 temperature requirements for bacterial growth. Explain the temperature ranges and where do infectious bacteria fall in the temperature range and requirements.arrow_forwardUsing your fingers, you are asked to aseptically touch the surface of a sterile agar plate. Illustrate the possible result from this step if your fingers are (a) unwashed – touched various things prior to placing on agar surface, and (b) washed with soap or disinfected with 70% alcohol. Describe the relative abundance of microbial growth observed on the plates. List and draw the possible characteristics of an isolated bacterial colony that can be observed based on type of (a) margin, (b) elevation, (c) texture, and (d) optical property.arrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
Human Anatomy & Physiology (11th Edition)BiologyISBN:9780134580999Author:Elaine N. Marieb, Katja N. HoehnPublisher:PEARSON
Biology 2eBiologyISBN:9781947172517Author:Matthew Douglas, Jung Choi, Mary Ann ClarkPublisher:OpenStax
Anatomy & PhysiologyBiologyISBN:9781259398629Author:McKinley, Michael P., O'loughlin, Valerie Dean, Bidle, Theresa StouterPublisher:Mcgraw Hill Education,
Molecular Biology of the Cell (Sixth Edition)BiologyISBN:9780815344322Author:Bruce Alberts, Alexander D. Johnson, Julian Lewis, David Morgan, Martin Raff, Keith Roberts, Peter WalterPublisher:W. W. Norton & Company
Laboratory Manual For Human Anatomy & PhysiologyBiologyISBN:9781260159363Author:Martin, Terry R., Prentice-craver, CynthiaPublisher:McGraw-Hill Publishing Co.
Inquiry Into Life (16th Edition)BiologyISBN:9781260231700Author:Sylvia S. Mader, Michael WindelspechtPublisher:McGraw Hill Education
Human Anatomy & Physiology (11th Edition)
Biology
ISBN:9780134580999
Author:Elaine N. Marieb, Katja N. Hoehn
Publisher:PEARSON
Biology 2e
Biology
ISBN:9781947172517
Author:Matthew Douglas, Jung Choi, Mary Ann Clark
Publisher:OpenStax
Anatomy & Physiology
Biology
ISBN:9781259398629
Author:McKinley, Michael P., O'loughlin, Valerie Dean, Bidle, Theresa Stouter
Publisher:Mcgraw Hill Education,
Molecular Biology of the Cell (Sixth Edition)
Biology
ISBN:9780815344322
Author:Bruce Alberts, Alexander D. Johnson, Julian Lewis, David Morgan, Martin Raff, Keith Roberts, Peter Walter
Publisher:W. W. Norton & Company
Laboratory Manual For Human Anatomy & Physiology
Biology
ISBN:9781260159363
Author:Martin, Terry R., Prentice-craver, Cynthia
Publisher:McGraw-Hill Publishing Co.
Inquiry Into Life (16th Edition)
Biology
ISBN:9781260231700
Author:Sylvia S. Mader, Michael Windelspecht
Publisher:McGraw Hill Education
cell culture and growth media for Microbiology; Author: Scientist Cindy;https://www.youtube.com/watch?v=EjnQ3peWRek;License: Standard YouTube License, CC-BY