Biology module 3 - 2.sexual reproduction in flowering plants 2.2 describe the structure of the ovule and the formation of embryo sac

2.2 describe the structure of the ovule and the formation of embryo sac

diagram ovule 

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Ovum (Egg) - female gamete

Polar nuclei - later fuse to form diploid nucleus

Antipodal and synergids appear to have no function and eventually disintegrate

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Formation of embryo sac

Diagram of formation of embryo sac

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• In the center of each ovule the embryo sac mother cells divide by mitosis to form 4 haploid cells

• 3 degenerate and 1 haploid cell grows to form the embryo sac

• the haploid cell divides by mitosis to form eight haploid nuclei