Multiple fission

…Mature cells rejuvenate by division, so in single-celled organisms, where the mother cell is reborn as two young individuals by binary fission, there is no death of the individual due to old age, which is inevitable in multicellular organisms. Division in which nuclear division continues without division of the cytoplasm to produce a multinucleated state, and then the cytoplasm is divided equally according to the number of nuclei, is called multiple fission, and is seen in foraminifera, radiolaria, malaria parasites, etc. Division in multicellular organisms is also called schizontism, and is seen in coelenterates and flatworms (turbinates), etc. …

*Some of the terminology explanations that mention "multiple fission" are listed below.

Source | Heibonsha World Encyclopedia 2nd Edition | Information

…成熟した細胞は分裂によって若返るので，2分裂によって母体が二つの若い個体に転生する単細胞生物には，多細胞生物に宿命的な老衰による個体の死は存在しない。細胞質の分裂をともなわないで核分裂が続行して多核状態となり，その後に核の数に応じて細胞質が等分される分裂を多分裂multiple fissionといい，有孔虫，放散虫，マラリア病原虫などにみられる。多細胞生物の分裂は分体ともいい，腔腸動物や扁形動物(渦虫類)などにみられる。…

※「multiple fission」について言及している用語解説の一部を掲載しています。

出典｜株式会社平凡社世界大百科事典 第２版について | 情報