Sarcodina Sar·co·di·na (sär'kō-dī'nə, -dē'-)
A superclass of protozoans that includes the rhizopods.
any protozoan of the superclass (sometimes class or subphylum) Sarcodina. These organisms have streaming cytoplasm and use temporary cytoplasmic extensions called pseudopodia in locomotion (called amoeboid movement) and feeding. Sarcodines include the genus Amoeba (see amoeba) and pathogenic species, e.g., dysentery-causing Entamoeba histolytica. These protozoans' cells may be spherical or irregular in shape; the pellicle (or envelope) is usually thin and flexible. Sometimes there is an external shell (see foraminiferan) or skeleton (see radiolarian). The cytoplasm, composed of ectoplasm and endoplasm, may contain more than one nucleus. Food, which adheres to the body surface or is trapped by pseudopodia, is digested in food vacuoles.
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