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Monosporic development refers to the development of embryo sac (female gametophyte) from a single functional megaspore.

Megaspore mother cell (MMC) undergoes meiosis to form 4 haploid megaspores. Out of the 4 megaspores, 3 megaspores degenerate while only one remains functional. This functional megaspores gives rise to the female gametophyte. Such a type of development of embryo sac from a single megaspore is called monosporic development.

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