Seed bag

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Schematic representation of a seedling with a seed bag inside. A - germinated window, B - chalazal end, C - ovum, D - synergides, E - polar nuclei, F - antipodes.

Embryo embryo sac - Simplified female gametophytes in seminal plants, resulting from the megasporogenesis process within the center (macrosporangium). Ripe seedlings are usually composed of a diploid central cell, an ovary on the lateral side of the eggshell (i.e. micropillar side), formed by an egg cell and two synergides, and three antipodes on the chalazal side.

In some species, the number of antipodes in the seed bag can reach several dozens, as a result of repeated cell division.

The seed bag is homologous with macrospora.

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