Podcast
Questions and Answers
What is the main limitation of the microscopic cell count method in bacterial enumeration?
What is the main limitation of the microscopic cell count method in bacterial enumeration?
- Presence of overlapping cells in high-density samples
- Difficulty in distinguishing between viable and non-viable cells (correct)
- Inability to calculate cell density accurately
- Problems with motile cells moving between grid squares
What is the purpose of using a Petroff-Hausser counting chamber in the microscopic cell count method?
What is the purpose of using a Petroff-Hausser counting chamber in the microscopic cell count method?
- To differentiate between Gram-positive and Gram-negative bacteria
- To calculate the volume of the bacterial suspension
- To count cells per unit area for calculating overall concentration (correct)
- To identify the bacteria species present in the culture
Why is it necessary to perform serial dilution on a bacterial broth culture before obtaining a countable number of viable bacteria?
Why is it necessary to perform serial dilution on a bacterial broth culture before obtaining a countable number of viable bacteria?
- To avoid interference from non-bacterial contaminants
- To ensure uniform distribution of bacterial cells in the culture
- To reduce the initial high cell density to a manageable range (correct)
- To prevent overestimation of the total cell count
What does a single, well-isolated colony on an agar plate represent in terms of bacterial replication?
What does a single, well-isolated colony on an agar plate represent in terms of bacterial replication?
What potential issue arises when motile cells are counted using the microscopic cell count method?
What potential issue arises when motile cells are counted using the microscopic cell count method?
What is the purpose of serial dilution in bacterial culture?
What is the purpose of serial dilution in bacterial culture?
What is the significance of subculturing/aliquoting after serial dilution?
What is the significance of subculturing/aliquoting after serial dilution?
Why is the drop plate method preferred over the spread plate method for bacterial enumeration?
Why is the drop plate method preferred over the spread plate method for bacterial enumeration?
Which direct method of bacterial enumeration is best suited for samples with low microbial concentrations like wastewater?
Which direct method of bacterial enumeration is best suited for samples with low microbial concentrations like wastewater?
In the pour-plate method, why is sterile medium added after pipetting the diluted culture onto a sterile plate?
In the pour-plate method, why is sterile medium added after pipetting the diluted culture onto a sterile plate?
