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Questions and Answers
Which organism is killed by atmospheric oxygen?
Which organism is killed by atmospheric oxygen?
In bacteria, toxic hydrogen peroxide can be broken down into water and oxygen by the enzyme:
In bacteria, toxic hydrogen peroxide can be broken down into water and oxygen by the enzyme:
What can be best defined as the time it takes for a cell to divide?
What can be best defined as the time it takes for a cell to divide?
Bacterial growth is usually graphed using ________ scales.
Bacterial growth is usually graphed using ________ scales.
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In which growth phase is there intense activity preparing for population growth, but no increase in population?
In which growth phase is there intense activity preparing for population growth, but no increase in population?
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In which growth phase is there intense activity preparing for population growth, but no increase in population?
In which growth phase is there intense activity preparing for population growth, but no increase in population?
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Which of the following is NOT a possible reason why exponential growth stops?
Which of the following is NOT a possible reason why exponential growth stops?
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In the stationary phase, what happens to microbial deaths and new cell formation?
In the stationary phase, what happens to microbial deaths and new cell formation?
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Which type of medium suppresses the growth of unwanted bacteria and encourages growth of desired microbes?
Which type of medium suppresses the growth of unwanted bacteria and encourages growth of desired microbes?
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What is the optimum pH for MOST bacteria?
What is the optimum pH for MOST bacteria?
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At what temperature would you expect a psychrophile to have its optimal growth?
At what temperature would you expect a psychrophile to have its optimal growth?
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What are organisms that require high salt concentrations for growth called?
What are organisms that require high salt concentrations for growth called?
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What is the primary energy source utilized by primary producers in hydrothermal vents on the ocean floor?
What is the primary energy source utilized by primary producers in hydrothermal vents on the ocean floor?
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Why does the addition of salts preserve foods?
Why does the addition of salts preserve foods?
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What is the optimal temperature for psychrophiles?
What is the optimal temperature for psychrophiles?
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Which type of organisms prefer acidic environments?
Which type of organisms prefer acidic environments?
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'Thermophiles' are organisms that thrive in which type of environment?
'Thermophiles' are organisms that thrive in which type of environment?
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What is the primary purpose of adding salts to preserve foods?
What is the primary purpose of adding salts to preserve foods?
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From where do chemoautotrophs and photoautotrophs derive their carbon?
From where do chemoautotrophs and photoautotrophs derive their carbon?
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What process involves some microorganisms using gaseous nitrogen directly from the atmosphere?
What process involves some microorganisms using gaseous nitrogen directly from the atmosphere?
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What do you call an organism that can grow without oxygen but uses it when present?
What do you call an organism that can grow without oxygen but uses it when present?
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Which type of organism is susceptible to being killed by atmospheric oxygen?
Which type of organism is susceptible to being killed by atmospheric oxygen?
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What effect does adding salts have on the osmotic pressure of foods?
What effect does adding salts have on the osmotic pressure of foods?
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Which compound is the primary source of carbon for chemoautotrophs and photoautotrophs?
Which compound is the primary source of carbon for chemoautotrophs and photoautotrophs?
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What type of organism uses oxygen only when it is present but can grow without it?
What type of organism uses oxygen only when it is present but can grow without it?
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What is the best technique to use to measure the growth of filamentous organisms?
What is the best technique to use to measure the growth of filamentous organisms?
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Which method is a statistical estimating technique used to determine the number of bacteria in a sample?
Which method is a statistical estimating technique used to determine the number of bacteria in a sample?
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Starting with one bacterial cell, how many cells would you have after 10 generations?
Starting with one bacterial cell, how many cells would you have after 10 generations?
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Which method is NOT suitable for determining the number of bacteria in a sample?
Which method is NOT suitable for determining the number of bacteria in a sample?
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What is the primary limitation of using turbidity to estimate bacterial numbers?
What is the primary limitation of using turbidity to estimate bacterial numbers?
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Which technique would be most suitable for quantifying bacteria that tend to form colonies and clumps?
Which technique would be most suitable for quantifying bacteria that tend to form colonies and clumps?
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What characteristic makes the Most Probable Number method especially useful for low-density bacterial samples?
What characteristic makes the Most Probable Number method especially useful for low-density bacterial samples?
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What is a potential drawback of using the Spread Plate method compared to direct counts for estimating bacterial numbers?
What is a potential drawback of using the Spread Plate method compared to direct counts for estimating bacterial numbers?
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