Syncytium

A syncytium or symplasm (/sɪnˈsaɪtiəm/; plural syncytia; from Greek: σύν (syn) = "together" + κύτος (kytos) = "box, i.e. cell") is a multinucleated cell that can result from multiple cell fusions of uninuclear cells (i.e., cells with a single nucleus), in contrast to a coenocyte, which can result from multiple nuclear divisions without accompanying cytokinesis. The term may also refer to cells interconnected by specialized membrane with gap junctions, as seen in the heart muscle cells and certain smooth muscle cells, which are synchronized electrically in an action potential.

Another (correct and well-established) use of the word syncytium is found in animal embryology to refer to the coenocytic blastoderm embryos of invertebrates, such as Drosophila melanogaster.

In protists, syncytia can be found in some rhizarians (e.g., chlorarachniophytes, plasmodiophorids, haplosporidians) and acellular slime moulds, dictyostelids (amoebozoans) and acrasids (excavates).

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