Gymnosperms represent the earliest extant seed plants and include the tallest, broadest, and oldest of living organisms.  They are heterosporous, with tiny microgametophytes (pollen grains) developing just 2 sperm each.  Megagametophytes are relatively large, but always enclosed in an integument (that becomes the seed coat) and always remains attached as an ovule/immature seed to the mother sporophyte plant until the seeds are dispersed.  Gymnosperms are mostly woody shrubs to trees, and sometimes vines.  Seeds may be borne in cones, or on modified leaves/stems, but are always naked at the time of pollination.



Family Galleries

Cycads  [ Wikipedia ]

    • Cycadaceae

    • Zamiaceae

Ginkgo  [ Wikipedia ]

    • Ginkgoaceae

Conifers  [ Wikipedia ]

    • Pinaceae

    • Taxaceae

    • Cuppressaceae

    • Taxodiaceae

Gnetophytes  [ Wikipedia ]

    • Ephedraceae