Plant (organism)

From Citizendium
Revision as of 10:11, 5 March 2009 by imported>Dalton Holland Baptista
Jump to navigation Jump to search
This article is a stub and thus not approved.
Main Article
Discussion
Related Articles  [?]
Bibliography  [?]
External Links  [?]
Citable Version  [?]
 
This editable Main Article is under development and subject to a disclaimer.
Plantae
Cypripedium reginae
Cypripedium reginae
Scientific classification
Domain: Eukaryota
Kingdom: Plantae
Haeckel 1866
Divisions

Plants, green plants, or just Plantae, is a group of living beings that have gone through several definitions along history, although, according to phylogeny concepts, it is accepted today that they are the organisms which belong to the kingdom Viridiplantae, as a monophyletic eukaryotic group of beings with cells recovered by a mostly cellulose made wall; which carry photosyntheses using chlorophyll types a and b, present in chloroplasts; and keep their products, such as amid; therefore some algae, and all fungi and bacteria are not technically considered members of this group anymore.

The exact number of plant species is unknown but it is consensus they are more than 285.000 and some assume they may be circa 350.000. From these, only about 20.000 do not produce flowers. Trees, grasses, vines, cacti, bushes, mosses and ferns are some well known plants.

Despite Phylogeny is changing many of the concepts as how plants should be classified an what are the divisions to stay, so far plants are informally divided among four groups main called green algae, about 8.000 species; non vascular plants, or Bryophytes, circa 20.000 species; the ferns and horsetails, or Pteridophytes, around 12.000; and seed plants, that is the largest group with 260.000 estimated species. These are split in twelve total divisions:

  1. Chlorophyta: part of green algae
  2. Charophyta: the rest of green algae
  3. Marchantiophyta: liverworts
  4. Anthocerotophyta: hornworts
  5. Bryophyta: mosses
  6. Lycopodiophyta: club mosses
  7. Pteridophyta: ferns
  8. Cycadophyta: cycads
  9. Ginkgophyta: ginkgo
  10. Pinophyta: conifers
  11. Gnetophyta: gnetophytes
  12. Magnoliophyta: flowering plants