In an angiosperm ovule, a specific diploid cell in the micropylar region of the nucellus undergoes one reduction division. Out of the four resulting cells, three degenerate. The single surviving cell then undergoes three successive strictly free-nuclear equational divisions. Following these divisions, cell walls are laid down. What is the exact cellular organization and ploidy of the final mature structure formed by

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The diploid cell in the nucellus is the Megaspore Mother Cell (MMC). It undergoes a reduction division (meiosis) to form four haploid megaspores. Three degenerate, leaving one functional haploid megaspore. This functional megaspore undergoes three successive free-nuclear equational divisions (mitosis), resulting in 2, then 4, and finally 8 haploid nuclei. After the 8-nucleate stage, cell walls are laid down leading to the organization of the typical female gametophyte (embryo sac). Six of the eight nuclei are surro