Explain what 'water potential' is, and how it relates to bacterial cell death. (3 marks)

(1) Water potential is the measure of potential energy in water.(2) Water potential determines the tendency of water to move from one location to another, via osmosis. (3) If bacteria is surrounded with a solution that has a more negative water potential than the cytoplasm of the bacteria, then water will move out of the bacteria cell. This will lead to cell lysis.

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