The gymnosperms are a group of seed A seed ( /ˈsiːd/ ) is a small embryonic plant enclosed in a covering called the seed coat, usually with some stored food. It is the product of the ripened ovule of gymnosperm and angiosperm plants which occurs after fertilization and some growth within the mother plant. The formation of the seed completes the process of reproduction in seed-bearing plants Plants are living organisms belonging to the kingdom Plantae. They include familiar organisms such as trees, herbs, bushes, grasses, vines, ferns, mosses, and green algae. The scientific study of plants, known as botany, has identified about 350,000 extant species of plants, defined as seed plants, bryophytes, ferns and fern allies. As of 2004, that includes conifers The conifers, division Pinophyta, also known as division Coniferophyta or Coniferae, are one of 13 or 14 division level taxa within the Kingdom Plantae. Pinophytes are gymnosperms. They are cone-bearing seed plants with vascular tissue; all extant conifers are woody plants, the great majority being trees with just a few being shrubs. Typical, cycads Cycads are seed plants characterized by a large crown of compound leaves and a stout trunk. They are evergreen, gymnospermous, dioecious plants having large pinnately compound leaves. They are frequently confused with and mistaken for palms or ferns, but are only distantly related to both, and instead belong to the division Cycadophyta, Ginkgo Ginkgo is a genus of highly unusual non-flowering plants with one extant species, G. biloba, which is regarded as a living fossil and Gnetales Gnetum is a genus of about 30-35 species of gymnosperms, the sole genus in the family Gnetaceae and order Gnetales. They are tropical evergreen trees, shrubs and lianas. Unlike other gymnosperms they possess vessel elements in the xylem. The term "gymnosperm" comes from the Greek Greek , an independent branch of the Indo-European family of languages, is the language of the Greeks. Native to the southern Balkans, it has the longest documented history of any Indo-European language, spanning 34 centuries of written records. In its ancient form, it is the language of classical ancient Greek literature and the New Testament of word gymnospermos (γυμνόσπερμος), meaning "naked seeds", after the unenclosed condition of their seeds (called ovules Ovule literally means "small egg." In seed plants, the ovule is the structure that gives rise to and contains the female reproductive cells. It consists of three parts: The integuments forming its outer layer, the nucellus , and the megaspore-derived female gametophyte (or megagametophyte) in its center. The megagametophyte (also called in their unfertilized state). Their naked condition stands in contrast to the seeds or ovules of flowering plants (angiosperms The flowering plants or angiosperms are the most diverse group of land plants. The flowering plants and the gymnosperms are the only extant groups of seed plants. The flowering plants are distinguished from other seed plants by a series of apomorphies, or derived characteristics) which are enclosed during pollination. Gymnosperm seeds develop either on the surface of scale- or leaf-like appendages of cones A cone is an organ on plants in the division Pinophyta (conifers) that contains the reproductive structures. The familiar woody cone is the female cone, which produces seeds. The male cones, which produce pollen, are usually herbaceous and much less conspicuous even at full maturity. The name "cone" derives from the fact that the shape, or at the end of short stalks (Ginkgo).
The gymnosperms and angiosperms together comprise the spermatophytes The spermatophytes (also known as phanerogams) comprise those plants that produce seeds. They are a subset of the embryophytes or land plants. The living spermatophytes form five groups: or seed plants The spermatophytes (also known as phanerogams) comprise those plants that produce seeds. They are a subset of the embryophytes or land plants. The living spermatophytes form five groups:. By far the largest group of living gymnosperms are the conifers (pines, cypresses, and relatives), followed by cycads, Gnetales (Gnetum Gnetum is a genus of about 30-35 species of gymnosperms, the sole genus in the family Gnetaceae and order Gnetales. They are tropical evergreen trees, shrubs and lianas. Unlike other gymnosperms they possess vessel elements in the xylem. Some species have been proposed to have been the first plants to be insect pollinated as they occur in, Ephedra Ephedra is a genus of gymnosperm shrubs, the only genus in the family Ephedraceae and order Ephedrales. These plants occur in dry climates over a wide area mainly in the northern hemisphere, across southern Europe, north Africa, southwest and central Asia, southwestern North America, and, in the southern hemisphere, in South America south to and Welwitschia Welwitschia is a monotypic genus of gymnosperm plant, composed solely of the very distinct Welwitschia mirabilis. It is the only genus of the family Welwitschiaceae, in the order Welwitschiales, in the division Gnetophyta. The plant is named after the Austrian botanist Friedrich Welwitsch who discovered it in 1859 and is considered a living fossil), and Ginkgo (a single living species).
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The presence of scorpionfly taxa suggests that siphonate proboscides fed on gymnosperm pollination drops and likely engaged in pollination mutualisms with ...
