Vacuole

The vacuole is a space inside the cell that is bounded by a phospholipid membrane.  This space is used to bring large food particles into the cell that cannot fit through the membrane proteins.  It is produced by a process of transport called endocytosis.  This is where the cell makes an indentation in the cell membrane in the area of the food particle.  The membrane then wraps itself around the particle as it gets closer to the center of the cell until it is fully wrapped in phospholipid membranes.  The reverse is used to expel wastes from the cell and is called exocytosis.  There are a couple different types of vacuoles.  Food vacuoles, which contain large food particles.  Waste vacuoles contain wastes that would poison the cell if not contained, and water vacuoles control the amount of water the stays inside the cell.  These are often seen in excellent detail in an amoeba. 

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