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guard cell

plant anatomy

Learn about this topic in these articles:

angiosperms

  • snake gourd flower
    In angiosperm: Dermal tissue

    …the epidermis are paired, chloroplast-containing guard cells, and between each pair is formed a small opening, or pore, called a stoma (plural: stomata). When the two guard cells are turgid (swollen with water), the stoma is open, and, when the two guard cells are flaccid, it is closed. This controls…

    Read More

stomate

  • stomata
    In stomate

    …internal pressure of two sausage-shaped guard cells that surround it. The inner wall of a guard cell is thicker than the outer wall. When the guard cell is filled with water and it becomes turgid, the outer wall balloons outward, drawing the inner wall with it and causing the stomate…

    Read More
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vacuole
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plant cell endocytosis and exocytosis plant cells and tissues Bacterial, animal, and plant cells compared organelles of eukaryotic cells
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plant cell
plant cell Plant cells contain membrane-bound organelles, including fluid-filled spaces, called vacuoles, that play an important role in maintaining the rigidity of a plant.

vacuole

biology
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endocytosis and exocytosis
endocytosis and exocytosisEndocytosis and exocytosis are fundamental to the process of intracellular digestion. Food particles are taken into the cell via endocytosis into a vacuole. Lysosomes attach to the vacuole and release digestive enzymes to extract nutrients. The leftover waste products of digestion are carried to the plasma membrane by the vacuole and eliminated through the process of exocytosis.

vacuole, in biology, a space within a cell that is empty of cytoplasm, lined with a membrane, and filled with fluid. Especially in protozoa (single-celled eukaryotic organisms), vacuoles are essential cytoplasmic organs (organelles), performing functions such as storage, ingestion, digestion, excretion, and expulsion of excess water. The large central vacuoles often found in plant cells enable them to attain a large size without accumulating the bulk that would make metabolism difficult. Potent secondary metabolites, such as tannins or various biological pigments, are also sequestered in the vacuoles in plants, fungi, algae, and certain other organisms to protect the cell from self-toxicity.

The Editors of Encyclopaedia BritannicaThis article was most recently revised and updated by Melissa Petruzzello.
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