Podcast Beta
Questions and Answers
Temperature is a major environmental factor controlling microbial ______
growth
Temperature below which growth ceases, or lowest temperature at which microbes will ______
grow
Temperature at which its growth rate is the ______
fastest
Optimum temperature for acidophiles is in pH range ______
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Optimum temperature for alkalophiles is in pH range ______
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Most organisms grow best between pH 6 and 8, but some organisms have evolved to grow best at low or high pH. Acidophiles are organisms that grow best at ______ pH
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The internal pH of a cell must stay relatively close to neutral even though the external pH is highly acidic or basic. Acidophiles include Helicobacter pylori and ______ thiooxidans
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Alkaliphiles are organisms that grow best at ______ pH
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Water activity is the ratio of the vapor pressure of the air in equilibrium with a solution to the vapor pressure of pure water (aw 1.00). aw= P solute P water. Organisms which thrive in high solute are called ______
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In nature, osmotic effects are of interest mainly in habitats with high salt environments that have reduced water availability. Halophiles are organisms that have evolved to grow best at reduced water potential, and some (extreme halophiles e.g. Halobacterium, Dunaliella ) even require high levels of salts for growth. Halotolerant organisms can tolerate some reduction in the water activity of their environment but generally grow best in the absence of the added ______
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