Gymnosperm and Angiosperm Seeds

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The term gymnosperm is derived from two Greek words: gymnos, meaning naked, and sperma, meaning seed. The term refers to plants, such as pine and spruce, in which seeds mature on the surface of cone scales. In contrast, the term angiosperm means a seed contained in a vessel and refers to flowering plants, in which seeds mature within a fruit.



The seeds of angiosperms develop in an ovary, a part of the carpel that surrounds and protects the egg-containing ovules. Seeds develop from the ovules after pollination and fertilization of the eggs. Ovules and seeds are not exclusive to angiosperms. The “naked-seed” plants (see Gymnosperm), which include the conifers, cycads, and ginkgo, have ovules that lie exposed on the surface of specialized, scalelike leaves arranged into cones. The development of seeds from ovules enclosed in an ovary, which enlarges into a fruit as the fertilized seeds grow, is a feature unique to the angiosperms.

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