Laboratory Experiments in Microbiology (11th Edition)
11th Edition
ISBN: 9780321994936
Author: Ted R. Johnson, Christine L. Case
Publisher: PEARSON
expand_more
expand_more
format_list_bulleted
Concept explainers
Textbook Question
Chapter 7, Problem 1CT
Suppose you performed a
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solutionStudents have asked these similar questions
Why is it important to perform a gram stain for any type of bacteria? After performing the gram stain method what would be the next step? (Think in terms of the real-world situation) Explain.
Suppose you are staining three identical smears of the same bacterial culture with three different basic simple stains: carbol fuschin, crystal violet and methylene blue. You observe each stained preparation under oil immersion at 100X. which of the following bacterial characteristics would you expect to be different between each of the stains as you view them under the microscope.
Bacterial arrangement
Bacterial shape
Size of cells
The color of the bacteria
Considering you can’t identify bacteria from a Gram stain, why might a physician perform a Gram stain on a sample before prescribing an antibiotic?
Chapter 7 Solutions
Laboratory Experiments in Microbiology (11th Edition)
Ch. 7 - Why do gram-positive cells more than 24 hours old...Ch. 7 - Can iodine be added before the primary stain in a...Ch. 7 - Prob. 3QCh. 7 - Which step can you omit without affecting...Ch. 7 - Suppose you performed a Gram stain on a sample...Ch. 7 - Prob. 2CTCh. 7 - Human cells can be stained with crystal violet and...Ch. 7 - Considering that it isnt possible to identity...
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
- After conducting the Gram staining procedures and you observe nothing (you didn’t see anything) in your slide under the microscope, what could be the mistake you have done? What can you observe when you view a Gram stained-mixture of bacterial specimen?arrow_forwardSuppose you are viewing a Gram-stained field of red rods and purple cocci through the microscope. What do you conclude?arrow_forwardAn acid-staining method was performed on a bacterial smear using the dyes carboifuchsin and methylene blue. The resulting stained slide contained only cells that appeared blue when visualized using a microscope. Which of the following couid explain why only blue cells were present?arrow_forward
- When performing a Gram stain on a Gram-negative bacteria, why does the bacteria stain pink? Crystal violet stain binds to iodine and remains in the bacterial cell wall because of the thick peptidoglycan layer. Safranin counterstain gets in the bacteria’s cell wall to stain the cell pink. The alcohol wash removes crystal violet and iodine from the bacteria. Crystal violet stain binds to iodine and remains in the bacteria cell wall because of the thick peptidoglycan layer AND Safranin counterstain gets in the bacteria’s cell wall to stain the cell pink. Safranin counterstain gets in the bacteria’s cell wall to stain the cell pink AND The alcohol wash removes crystal violet and iodine from the bacteria.arrow_forwardIf there are bacterial clumps visible in a drop of water on a glass slide, will this affect the staining of the bacteria? If there are bacterial clumps visible in a drop of water on a glass slide, will this affect the staining of the bacteria? No; the clumps will wash away later. Yes; the clumps will hide the individual bacteria. The clumps will not stain. Yes; the clumps of bacterial cells may retain the stains and lead to incorrect data being collected. SubmitRequest Answerarrow_forwardIf you were working with an unlabeled simple stained smear, would you be able to identify the bacterial species by observing the slide under the microscope? Why or why not?arrow_forward
- Imagine that you are Gram staining a mixed culture of both gram-positive and gram-negative bacteria. If you omitted the iodine (mordant) step in the procedure, what colors would the bacteria on your slide appear to be? ► The gram-positive bacteria would be purple, and the gram-negative would be pink All of the bacteria would look purple All of the bacteria would look pink The bacteria would not be stained at all (clear)arrow_forwardWhen you use a simple stain like Methylene blue, how can you tell between one bacterium and another bacterium?arrow_forwardYou have spread 0.1ml of a 1x10-8 diluted bacterial culture sample on a Petridish and counted35 colonies. What was the cell density of your original culture (in cells/ml)? How many cellsdid you have in 100ml of that culture? DON’T FORGET TO ROUND!arrow_forward
- Suppose that you are viewing a Gram-stained field of red rods and purple cocci through the microscope. What can you conclude about your culture?arrow_forwardBased from the results obtained from Gram staining, explain why bacterial cells retained or changed their color. Briefly explain the principle behind the procedure. Cite advantages of differential staining method (Gram staining and endospore staining) over simple staining only. List other staining methods aside from those you performed in the laboratory. conclusion:arrow_forwardWhat is the principle of Grams staining based on the cell wall composition of bacterial cell.arrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
cell culture and growth media for Microbiology; Author: Scientist Cindy;https://www.youtube.com/watch?v=EjnQ3peWRek;License: Standard YouTube License, CC-BY