A vacuole (of the Latin vaccuus , vacuum) is a cellular Organite delimited by simple a membrane. According to the taxon, one distinguishes the vacuoles from the cell Animal are and those of the cells Végétal be. Certain unicellular organizations, generally living out of fresh water, also have some.

Animal cell

The vacuoles of condensation , present at some secreting cells (like the cells of the Pancreas or the blisters filled with Neuro-transmitter S) constitute then grains of secretions, resulting from the fusion of blisters of secretion produced by the Appareil of Golgi.

Vegetable cell

• the central vacuole of the vegetable cells and mushrooms has a homeostatic function , ensuring the cellular Turgescence, and its membrane, the Tonoplaste, has ionic pumps . It contains Eau, Glucide S, ions organic and inorganic and Pigment S. Some central vacuoles are also sites of accumulation of reserves or particular substances, sometimes toxic (latex, Opium…) even of waste what confers to them a role of detoxification of the cell.

The vacuole represents between 80 and 90% of the cellular volume of the adult vegetable cell. Its contents primarily consist of sometimes crystallized solutions. Thus the reserves of saccharose at beet and the cane with sugar or of Inuline at the Astéracées (Made up) are accumulated in solution in the vacuoles of their cells. Reserves of malate can also play a big role in the photosynthetic function of certain fatty plants (photosynthesis of the CAMWOOD type which uses the malate like forms storage of CO₂ in preparation for the hottest periods of the day). In fact the molecules of the endoplasmic reticulum smoothes generate the vacuoles. The vacuoles can also protect the plant against the predatory ones, because they contain sometimes compounds toxic or unpleasant to the taste. The vacuole plays a central role in the growth of the vegetable cell.

Unicellular organizations

• the contractile vacuoles are present at certain Eucaryote S Unicellulaire S (in the past called Protozoaire S) alive out of fresh water. These vacuoles make it possible to evacuate water in excess in the Cytoplasme but also the locomotion by antiphasic contraction.
• the vacuole of Phagocytose meets at the unicellular ones nourishing by invagination of the plasmic Membrane around a Proie. This type of vacuole enters in coalescence with Lysosome S, and, after digestion opens outside, rejecting the not digested elements.

Simple: Vacuole

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