megaspore

megaspore

Four haploid cells produced by meiosis in the ovule of a þower. Usually, three of these cells degenerate, with the remaining cell becoming the female gametophyte phase of the plant's life cycle. Large (palynologists consider the megaspores to generally be above 200 micrometers in diameter) spores that develop into the megagametophyte, which in turn produces eggs.

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الفئة: بيولوجيا الخلايا
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