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macrocyst

n. (context biology English) An aggregate of cells of Dictyosteliida formed during sexual reproduction enclosed in a cellulose wall.

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Macrocyst

A macrocyst is an aggregate of cells of Dictyosteliida formed during sexual reproduction enclosed in a cellulose wall.

If two amoebae of different mating types are present in a dark and wet environment, they can fuse during aggregation to form a giant cell. The giant cell will then engulf the other cells in the aggregate and encase the whole aggregate in a thick, cellulose wall to protect it. This is known as a macrocyst. Inside the macrocyst, the giant cell divides first through meiosis, then through mitosis to produce many haploid amoebae that will be released to feed as normal amoebae would.