All Topics  
Spermatophyte

 

   Email Print
   Bookmark   Link






 

Spermatophyte



 
 
The spermatophytes (from the Greek word "Spe?ľat?f?ta") (also known as phanerogams) comprise those plant
Plant

Plants are Life organisms belonging to the Kingdom Plantae. They include familiar organisms such as trees, herbs, bushes, grasses, vines, ferns, mosses, and green algae....
s that produce seed
Seed

A seed is a small Plant embryogenesis plant enclosed in a covering called the seed coat, usually with some Food storage. It is the product of the ripened ovule of gymnosperm and angiosperm plants which occurs after fertilization and some growth within the mother plant....
s. They are a subset of the embryophyte
Embryophyte

The embryophytes are the most familiar group of plants. They include trees, flowers, ferns, mosses, and various other green land plants. All are complex multicellular eukaryotes with specialized reproductive organs....
s or land plants. The living spermatophytes form five groups:



In addition to the taxa listed above, the fossil record contains evidence of many extinct taxa of seed plants. The so-called "seed ferns" (Pteridospermae) were one of the earliest successful groups of land plants, and forests dominated by seed ferns were prevalent in the late Paleozoic
Paleozoic

The Paleozoic or Palaeozoic Era is the earliest of three geology Era of the Phanerozoic Eon . The Paleozoic spanned from roughly , and is subdivided into six period ; from oldest to youngest they are: the Cambrian, Ordovician, Silurian, Devonian period, Carboniferous, and Permian...
.






Discussion
Ask a question about 'Spermatophyte'
Start a new discussion about 'Spermatophyte'
Answer questions from other users
Full Discussion Forum



Encyclopedia


The spermatophytes (from the Greek word "Spe?ľat?f?ta") (also known as phanerogams) comprise those plant
Plant

Plants are Life organisms belonging to the Kingdom Plantae. They include familiar organisms such as trees, herbs, bushes, grasses, vines, ferns, mosses, and green algae....
s that produce seed
Seed

A seed is a small Plant embryogenesis plant enclosed in a covering called the seed coat, usually with some Food storage. It is the product of the ripened ovule of gymnosperm and angiosperm plants which occurs after fertilization and some growth within the mother plant....
s. They are a subset of the embryophyte
Embryophyte

The embryophytes are the most familiar group of plants. They include trees, flowers, ferns, mosses, and various other green land plants. All are complex multicellular eukaryotes with specialized reproductive organs....
s or land plants. The living spermatophytes form five groups:

  • cycad
    Cycad

    File:Cycad cone.jpgCycads are a group of seed plants characterized by a large crown of compound Leaf and a stout trunk . They are evergreen, gymnospermous, dioecious plants having large pinnately compound leaves....
    s, a subtropical and tropical group of plants with a large crown of compound leaves and a stout trunk,
  • Ginkgo
    Ginkgo

    Ginkgo , frequently misspelled as "Gingko", and also known as the Maidenhair Tree after Adiantum, is a unique species of tree with no close living relatives....
    , a single living species of tree
    TREE

    TREE was a Boston hardcore punk band formed in the summer of 1990. They were active in the Boston music scene until disbanding in 2002....
    ,
  • conifers, cone-bearing trees and shrub
    Shrub

    A shrub or bush is a horticulture rather than strictly Botany category of woody plant, distinguished from a tree by its multiple stems and lower height, usually less than 5-6 m tall....
    s,
  • gnetophytes, woody plant
    Woody plant

    A woody plant is a Vascular tissue plant that has a Perennial plant Plant stem that is above ground and covered by a layer of thickened bark. Woody plants are adapted to survive from one year to the next; the stem supports continued vegetative growth above ground from one year to next....
    s in the genera Gnetum
    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....
    , Welwitschia
    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....
    , and Ephedra
    Ephedra (genus)

    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 A...
    , and
  • angiosperms, the flowering plants, a large group including many familiar plants in a wide variety of habitats.


In addition to the taxa listed above, the fossil record contains evidence of many extinct taxa of seed plants. The so-called "seed ferns" (Pteridospermae) were one of the earliest successful groups of land plants, and forests dominated by seed ferns were prevalent in the late Paleozoic
Paleozoic

The Paleozoic or Palaeozoic Era is the earliest of three geology Era of the Phanerozoic Eon . The Paleozoic spanned from roughly , and is subdivided into six period ; from oldest to youngest they are: the Cambrian, Ordovician, Silurian, Devonian period, Carboniferous, and Permian...
. Glossopteris
Glossopteris

Glossopteris is the largest and best-known genus of the Extinction Order of seed ferns known as Glossopteridales ....
 was the most prominent tree
TREE

TREE was a Boston hardcore punk band formed in the summer of 1990. They were active in the Boston music scene until disbanding in 2002....
 genus
Genus

A genus is a low-level taxonomic rank used in the classification of living and fossil organisms. The taxonomic ranks are domain , kingdom , phylum, class , order , family , genus, and species....
 in the ancient southern supercontinent
Supercontinent

In geology, a supercontinent is a landmass comprising more than one continental core, or craton. The assembly of cratons and terrane that form Eurasia qualifies as a supercontinent today....
 of Gondwana
Gondwana

Gondwana , originally Gondwanaland is the name given to a southern precursor-supercontinent and then as a remnant separated from Laurasia 180- during the breakup of the Pangaea supercontinent that existed about 500 to 200 Annum ago into two large segments.
 during the Permian
Permian

The PermianThe term "Permian" was introduced into geology in 1841 by Sir Roderick Murchison, president of the Geological Society of London, who identified typical strata in extensive Russian explorations undertaken with Edouard de Verneuil; Murchison asserted in 1841 that he named his "Permian system" after the ancient kingdom...
 period. By the Triassic
Triassic

The Triassic is a geologic period that extends from about 251 to 199 annum . As the first period of the Mesozoic Era, the Triassic follows the Permian and is followed by the Jurassic....
 period, seed ferns had declined in ecological importance, and representatives of modern gymnosperm groups were abundant and dominant through the end of the Cretaceous
Cretaceous

The Cretaceous , usually abbreviated K for its German translation Kreide, is a geologic period from circa to million years ago . In the geologic timescale, the Cretaceous follows on the Jurassic period and is followed by the Paleogene period....
, when angiosperms radiated. Another Late Paleozoic group of probable spermatophytes were the gigantopterid
Gigantopterid

Gigantopterids is the name given to fossils of a group of plants existing in the Late Permian, until some 250 million years ago. Gigantopterids were among the most advanced land plants of the Paleozoic and disappeared soon after the massive Permian?Triassic extinction event 251.4 million years ago....
s.

Relationships and nomenclature


Seed-bearing plants were traditionally divided into angiosperms, or flowering plants, and gymnosperm
Gymnosperm

Gymnosperm is a group of spermatophyte seed-bearing plants with ovules on scales, which are usually arranged in cone-like structures. The other major group of seed-bearing plants, the angiosperms, [from the Greek, 'angion' - container] have ovules enclosed in a carpel, a sporophyll with fused margins....
s, which includes the gnetophytes, cycads, ginkgo, and conifers. Older morphological studies have shown a close relationship between the gnetophytes and the angiosperms, in particular based on vessel elements. However, molecular studies (and some more recent morphological and fossil papers) have generally shown a clade
Clade

A clade is a term used in modern alpha taxonomy, the scientific classification of living and fossil organisms, to describe a monophyletic group, defined as a group consisting of a single common ancestor and all its descendants.The term "monophyletic group" is used in this article in the conventional sense of "an a...
 of gymnosperm
Gymnosperm

Gymnosperm is a group of spermatophyte seed-bearing plants with ovules on scales, which are usually arranged in cone-like structures. The other major group of seed-bearing plants, the angiosperms, [from the Greek, 'angion' - container] have ovules enclosed in a carpel, a sporophyll with fused margins....
s, with the gnetophytes in or near the conifers. For example, one common proposed set of relationships is known as the gne-pine hypothesis and looks like:

The relationships between these groups should not be considered settled.

A traditional classification grouped put all the seed plants in a single division, with classes for our five groups:
  • Division Spermatophyta
    • Cycad
      Cycad

      File:Cycad cone.jpgCycads are a group of seed plants characterized by a large crown of compound Leaf and a stout trunk . They are evergreen, gymnospermous, dioecious plants having large pinnately compound leaves....
      opsida
      , the cycads
    • Ginkgo
      Ginkgo

      Ginkgo , frequently misspelled as "Gingko", and also known as the Maidenhair Tree after Adiantum, is a unique species of tree with no close living relatives....
      opsida
      , the ginkgo
    • Pinopsida, the conifers, ("Coniferopsida")
    • Gnetopsida, the gnetophytes
    • Magnoliopsida
      Magnoliopsida

      Magnoliopsida is a valid botanical name for a class of flowering plants. By definition the class will include the family Magnoliaceae, but its wiktionary:circumscription can otherwise vary, being more inclusive or less inclusive depending upon the classification system being discussed....
      , the flowering plant
      Flowering plant

      The flowering plants or angiosperms are the most widespread group of Embryophytes. The flowering plants and the gymnosperms are the only extant groups of Spermatophyte....
      s, or Angiospermopsida


A more modern classification ranks these groups as separate divisions (sometimes under the Superdivision Spermatophyta):
  • Cycad
    Cycad

    File:Cycad cone.jpgCycads are a group of seed plants characterized by a large crown of compound Leaf and a stout trunk . They are evergreen, gymnospermous, dioecious plants having large pinnately compound leaves....
    ophyta
    , the cycads
  • Ginkgo
    Ginkgo

    Ginkgo , frequently misspelled as "Gingko", and also known as the Maidenhair Tree after Adiantum, is a unique species of tree with no close living relatives....
    phyta
    , the ginkgo
  • Pinophyta
    Pinophyta

    The conifers, division Pinophyta, also known as division Coniferae, are one of 13 or 14 division level taxon within the Plant. They are Conifer cone-bearing seed plants with Vascular plant tissue; all extant conifers are woody plants, the great majority being trees with just a few being shrubs....
    , the conifers
  • Gnetophyta, the gnetophytes
  • Magnoliophyta
    Flowering plant

    The flowering plants or angiosperms are the most widespread group of Embryophytes. The flowering plants and the gymnosperms are the only extant groups of Spermatophyte....
    , the flowering plant
    Flowering plant

    The flowering plants or angiosperms are the most widespread group of Embryophytes. The flowering plants and the gymnosperms are the only extant groups of Spermatophyte....
    s