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Ovule

Structure found in seed plants that develops into a seed after fertilization. It consists of an embryo sac containing the female gamete (ovum or egg cell), surrounded by nutritive tissue, the nucellus. Outside this there are one or two coverings that provide protection, developing into the testa, or seed coat, following fertilization.

In angiosperms (flowering plants) the ovule is within an ovary, but in gymnosperms (conifers and their allies) the ovules are borne on the surface of an ovuliferous (ovule-bearing) scale, usually within a cone, and are not enclosed.


See also: Ovum



07-14-2008 23:18:10
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