syncytium

cell

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July 14, 2026

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A syncytium is a multinucleate mass of cytoplasm that results from the fusion of cells. This means that multiple cell nuclei share a single cytoplasm, without distinct cell boundaries.123

Syncytia can form through cell fusion or through repeated nuclear division without the separation of cytoplasm (cytokinesis). This process allows for coordinated gene expression to meet high metabolic or structural demands. Examples include the plasmodium stage of true slime molds and the voluntary muscles of humans. The term "syncytium" was first introduced by Ernst Haeckel in the 19th century to describe the tissue mass of calcareous sponges formed by the fusion of cells.231

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nucleus
…through cell fusion (forming a syncytium, as in skeletal muscle fibers) or through repeated nuclear division without cytokinesis (coenocytic cells). Some cells—such as mature mammalian red blood cells—lose their nuclei during development to help maximize space for oxygen transport.
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…through cell fusion (forming a syncytium, as in skeletal muscle fibers) or through repeated nuclear division without cytokinesis (coenocytic cells). Some cells—such as mature mammalian red blood cells—lose their nuclei during development to help maximize space for oxygen transport.
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reproduction
Multiple fission
The nuclei are in a syncytium, that is, there are no cell boundaries, and the nuclei flow freely in the motile plasmodium. As it feeds, the plasmodium enlarges, and the nuclei divide synchronously about once every 24 hours. The plasmodium may become very large, with millions of nuclei, but, ultimately,…
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The nuclei are in a syncytium, that is, there are no cell boundaries, and the nuclei flow freely in the motile plasmodium. As it feeds, the plasmodium enlarges, and the nuclei divide synchronously about once every 24 hours. The plasmodium may become very large, with millions of nuclei, but, ultimately,…
Read More