Ovule

plant structure. a small body in seed-bearing plants that consists of the integument(s), nucellus, and embryosac (containing the egg cell) and develops into the seed after fertilization

Ovules produce the female reproductive cells which get fertilized during sexual reproduction in seed plants.[1] The word literally means "small egg."[2][3]

Location of ovules inside a Helleborus foetidus flower
Cross section of an ovule of a pine tree. A=Gametophyte, B=Egg cell, C=Micropyle, D=Integument, E=Sporangium

The megagametophyte (also called the embryo sac in flowering plants) is inside the ovule. The megagametophyte produces the egg cell.

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