Each ovule possesses one or two integuments which enclose ovule except the micropyle.
Chalaza is the basal part of an ovule. The nucleus encloses a mass of cells. Emrbyo sac is 7 celled but 8 nucleate lies in the ovule. It is called female gameto phyte.
cell walls are laid down. Six of 8 nuclei are surrounded by cell walls and organized into the cells. The remaining 2 nuclei in
the centre of emrbyo sac are polar nuclei.
They lie below egg apparatus in the big central cell. Three cells at micropylar end form egg apparatus.
It has 2 synergids and one egg cell. Three other cells at chalzal end form antipodals. The big central cell has 2 nuclei. So mature 8 nucleate embryo sac is 7 celled.
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