The food vacuole, or digestive vacuole, is an organelle found in parasites that cause malaria. During the stage of the parasites' lifecycle where it resides within a human (or other mammalian) red blood cell, it is the site of haemoglobin digestion and the formation of the large haemozoin crystals that can be seen under a light microscope.
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Food vacuole Wikipedia(Text) CC BY-SA