Ovule

Common card · No. 387829

The ovule (from Latin: ovulum) is a small structure present in a seed plant's floral ovary that gives rise to and contains its female reproductive cells. It consists of three parts: the integument, forming its outer layer, the nucellus (or remnant of the megasporangium), and the female gametophyte (formed from a haploid megaspore) in its center. The female gametophyte — specifically termed a megagametophyte — is also called the embryo sac in angiosperms. The megagametophyte produces an egg cell for the purpose of fertilization. The ovule is attached to the placenta by a stalk called a "funicle" that nourishes it. On the basis of the relative position of micropyle, body of the ovule, chalaza and funicle, there are six types of ovules.

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