Questions and Answers
How is microbial growth defined?
Increase in cell number
What usually happens to the 'mother cell' before it divides?
It duplicates in size and contents
What is the process of cell division in bacteria called?
a and c
What occurs in binary fission that leads to cell division?
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When does DNA synthesis occur in continuously dividing cells?
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What special cell arrangements can result from incomplete separation of cells?
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How does cell division occur in yeast ?
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What is the main difference between binary fission and budding?
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What is the result of budding in terms of cell production?
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What is the ultimate outcome of microbial growth and cell division?
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What characterizes the lag phase of bacterial growth?
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What activities occur during the lag phase?
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What factors influence the length of the lag phase?
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In which phase do bacteria grow at an exponential rate?
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What is the generation time?
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What is the typical range for generation time in bacteria?
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How does the population size change in each generation time during the log phase?
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What is the defining characteristic of synchronous growth?
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What is the result of non-synchronous growth?
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What follows the log phase in bacterial growth?
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Why is the log phase limited in time in a flask or test tube?
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What can maintain log bacterial growth in a controlled environment?
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What happens in the stationary phase of bacterial growth?
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What characterizes the decline (death) phase of bacterial growth?
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How does growth occur in colonies on a solid medium?
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What is a colony-forming unit (CFU)?
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What is the result of continuous addition of fresh medium in a chemostat?
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What determines the duration of the decline (death) phase?
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How is the enumeration of bacteria measured?
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What is the principle behind the serial dilution and standard plate count method?
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Which method involves a series of dilutions followed by transferring 0.1ml to an agar plate?
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What is the pour plate method?
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What is a disadvantage of the pour plate method?
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How is the spread plate method performed?
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How is the concentration of bacterial cells in the original suspension calculated?
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What is the principle of the filtration method for bacterial enumeration?
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What are the other methods mentioned for bacterial enumeration?
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How is turbidity measured in bacterial enumeration?
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What is the purpose of shaking tubes before sampling in bacterial enumeration?
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What is the significance of the 30-300 CFU range in bacterial enumeration?
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What are the reasons microorganisms exist almost everywhere on earth?
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What are the physical factors influencing the type of organisms and their growth rates?
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Which classification of microorganisms is based on their tolerance to acidity or alkalinity?
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At what pH range do acidophiles typically grow best?
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Why do microorganisms usually not grow well at pH values significantly above or below their optimum pH?
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What protects the cell membrane of organisms that tolerate extreme pH levels?
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What is the optimal temperature range for psychrophiles?
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What is the classification of bacteria that can grow both below and above 20°C?
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What is the temperature range for thermophiles?
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Which group of bacteria includes those that can adjust and tolerate different environments?
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What type of bacteria cannot grow over 20°C?
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Which factor does NOT influence bacterial growth?
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What are the three classifications of bacteria based on their temperature preferences?
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What are the biochemical factors influencing bacterial growth?
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