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Apicomplexans, a group of intracellular parasites, have life cycle stages evolved to allow them to survive the wide variety of environments they are exposed to during their complex life cycle. Each stage in the life cycle of an apicomplexan organism is typified by a ''cellular variety'' with a distinct morphology and biochemistry. Not all apicomplexa develop all the following cellular varieties and division methods. This presentation is intended as an outline of a hypothetical generalised apicomplexan organism. ==Methods of asexual replication== Apicomplexans (sporozoans) replicate via ways of multiple fission (also known as schizogony). These ways include gametogony, sporogony and merogony, although the latter is sometimes referred to as schizogony, despite its general meaning. Merogony is an asexually reproductive process of apicomplexa. After infecting a host cell, a trophozoite (see glossary below) increases in size while repeatedly replicating its nucleus and other organelles.〔(【引用サイトリンク】title=Schizogony definition )〕 During this process, the organism is known as a meront or schizont. Cytokinesis next subdivides the multinucleated schizont into numerous identical daughter cells called merozoites (see glossary below), which are released into the blood when the host cell ruptures. Organisms whose life cycles rely on this process include ''Theileria'', ''Babesia'', as well as the malaria parasite ''Plasmodium''. Sporogony is a type of sexual and asexual reproduction. It involves karyogamy, the formation of a zygote which is followed by meiosis and multiple fission. This results in the production of sporozoites. Other forms of replication include endodyogeny and endopolygeny. Endogeny is a process of asexual reproduction, favoured by parasites such as ''Toxoplasma gondii''. It involves an unusual process in which two daughter cells are produced inside a mother cell, which is then consumed by the offspring prior to their separation. Endopolygeny is the division into several organisms at once by internal budding.〔 ==Glossary of cell types== 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Apicomplexan life cycle」の詳細全文を読む スポンサード リンク
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