The seed-producing vascular plants are the gymnosperms and angiosperms. Neither requires water for sperm to meet eggs. Gymnosperm seeds are not enclosed in fruits, and many lack vessels in the xylem. They have diverse leaves and reproductive structures. Gymnosperms include ginkgos, cycads, conifers, and gnetophytes.
Angiosperms appear rather suddenly in the fossil record and rapidly diversified.
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