Some of the more commonly found examples of gymnosperms are pines, spruces, cedars and sequoias. The less abundant varieties include the cycads, such as the sago palm, and the maidenhair tree or Ginkgo biloba. Overall, there are more than 1,000 species of gymnosperms encompassing 14 plant families.Know More
Gymnosperms are seed-bearing plants that do not produce fruits or flowers. They are heterosporous and produce gametophytes and spores that are embedded within their parental diploid tissues. The seeds of gymnosperms either develop on the scales or leaves of the plant, often in a protected manner such as the pine cone, or at the tips of short stalks, such as in the case of the Ginkgo biloba.
Together with the angiosperms, which produce fruits or flowers, gymnosperms represent the spermatophytes, or seed-producing plants. The conifers, most of which are evergreens, represent the widest variety of gymnosperms, with more than 600 species. Conifers are a source of a significant economic commodity in the form of lumber.
Gymnosperms are commonly accepted as the group from which the angiosperms evolved, but which particular group they came from remains, in the words of Charles Darwin, "an abominable mystery." A wide variety of gymnosperms have been suggested as possible ancestors of the fruit- and flower-producing angiosperms. It is believed that the gymnosperms themselves originated about 319 million years ago during the late Carboniferous period.Learn more about Botany
Pollination differs between angiosperms and gymnosperms in that most angiosperms entice animals to carry their pollen from plant to plant, while most gymnosperms rely on the wind carrying their pollen to other plants. There are many wind-pollinated angiosperms and a very few animal-pollinated gymnosperms, however. The methods angiosperms use tend to be more effective at spreading quickly, but gymnosperms, particularly conifers, are generally better adapted to cold or dry environments.Full Answer >
Distinguishing characteristics of the phylum Gnetophyta include the presence of both tracheids and vessels in their xylem tissue, a unique fertilization feature in which a tube grows from the eggs to unite with pollen tubes, and being the only division of gymnosperms that undergo double fertilization. Gnetophyta plants include trees, shrubs, or stumpy, turnip-like growth forms with simple leaves.Full Answer >
Pollen is produced in the stamen in angiosperms and is produced in the microsporangiate cones in gymnosperms. The cones that pollen is produced in are usually referred to as male cones or pollen cones.Full Answer >
Though angiosperms and gymnosperms are both seed-producing plants of the Embryophyta subkingdom, they share many more differences than similarities. The most significant regards seed development. While angiosperms produce seeds within an enclosure, the seeds of gymnosperms are not enclosed.Full Answer >