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Cell or Plasma Membranes

What is the function of plasma membrain?


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November 25, 2008 2:30AM

All cells have a plasma membrane that encloses their contents and serves as a barrier to the outside environment. The membrane acts as a boundary, holding the cell constituents together and keeping other substances from getting in. But the plasma membrane does allows nutrients and other essential elements to enter the cell and waste materials to leave the cell. Small molecules, such as oxygen, carbon dioxide, and water, are able to pass freely through the membrane, but the passage of larger molecules is controlled.