OSMOTIC PRESSURE

OSMOTIC PRESSURE - OSMOTICPRESSURE cell.. . Thisisawayof

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OSMOTIC PRESSURE Placing a high concentration of salt or sugar in bacterial surroundings causes water to leave the  cell. This is very similar to plain desiccation. It causes the plasma membrane to shrink away from  the cell wall---plasmolysis. The cell stops growing and eventually dies.  This is a way of preserving foods by preventing bacterial growth. Ham, bacon, salted fish, etc.  use high concentrations of salt. Jellies and fruit preserves use sugar. Yeasts and molds are better able to resist effects of both regular desiccation and osmotic  pressure, so they commonly cause spoilage of jelly, baked goods, etc. Bacteria grow poorly if at  all in these foods.   RADIATION 1. IONIZING RADIATION —this includes X rays, gamma rays, and high-energy electron  beams. These all have very short wavelengths and high levels of energy. They cause ionization of  water within cells, which results in formation of hydroxyl radicals. These destroy cell 
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This note was uploaded on 01/23/2012 for the course MCB MCB2010 taught by Professor Smith during the Fall '09 term at Broward College.

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