Plant Structure2 - the plant also loses an enormous amount...

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Plant Structures Stomata and Gas Exchange Stomata, as mentioned above, are the structures through which gas exchange occurs in leaves. Each stoma is surrounded by two guard cells, which can open and close depending on environmental conditions. When moisture is plentiful, the guard cells swell with water, forcing the opening of the stoma open and allowing gas exchange to occur. When the plant loses too much water or water in the environment becomes less plentiful, the guard cells deflate, closing the stoma and preventing further water loss or gas exchange. Figure %: Stoma and Guard Cells When the stomata are open, the plant can take in carbon dioxide from the air for photosynthesis and release oxygen (a byproduct of photosynthesis) back into the environment. While doing so,
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Unformatted text preview: the plant also loses an enormous amount of water by evaporation. This process is called transpiration. To make up for this water loss, additional water is drawn in from the soil by the roots and passed upward through the plant by the xylem. Gynoecium The gynoecium, composed of a pistil or pistils (or carpels, as they are also sometimes called), lies in the very middle of the flower. The top of the pistil, where pollen grains land, is called the stigma and the shaft leading down into the ovary is called the style. The ovary, containing ovules and egg cells, makes up the very bottom of the pistil...
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This note was uploaded on 01/27/2012 for the course BIOLOGY BSC1005 taught by Professor Rodriguez during the Winter '09 term at Broward College.

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