Plant (organism): Difference between revisions

From Citizendium
Jump to navigation Jump to search
imported>D. Matt Innis
(Dalton, just some copyedits - make sure I didn't change any meanings)
imported>Joshua Choi
(Starting to beef this article up)
Line 24: Line 24:
*[[Magnoliophyta]]  
*[[Magnoliophyta]]  
}}
}}
'''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 covered by a mostly cellulose made wall; which carry out [[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.
The '''green plants''' (from the Latin ''planta'', meaning "sprout") are those [[organism]]s classified into the [[kingdom (biology)|kingdom]] '''Plantae'''. Descending from a single [[common ancestor]], the plants take up a large portion of [[life]]—with estimates exceeding 285,000 [[species]]—and include many familiar and ubiquitous species including [[tree]]s, [[shrub]]s, [[cactus|cacti]], [[grass]]es, [[herb]]s, [[fern]]s, [[moss]]es, and [[green algae]]. Plants share certain characteristics—unlike [[animal]]s and [[fungi]], they do not voluntarily move, typically growing in a permanent site, passively absorbing [[nutrients]] and [[energy]] from their environment. In terms of both their total mass and their importance to other organisms, the green plants dominate [[ecosystem]]s in both [[land]] and [[freshwater]]. By harnessing [[sunlight]], they act as the primary sources of energy and [[food]] for all life in those ecosystems: green algae in freshwater and [[land plant]]s on the land.
 
==Usage of the term==
 
The term "plant" has gone through several definitions along history.
 
[[Green algae]], for instance, were traditionally classified as [[protist]]s, but recent evidence has moved them into the plants along with the land plants.
 
==Origin and phylogeny==


Despite Phylogeny changing many of the concepts of how plants should be classified and what divisions remain, currently plants are informally divided among four main groups 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:
Despite Phylogeny changing many of the concepts of how plants should be classified and what divisions remain, currently plants are informally divided among four main groups 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:

Revision as of 15:40, 3 May 2009

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

The green plants (from the Latin planta, meaning "sprout") are those organisms classified into the kingdom Plantae. Descending from a single common ancestor, the plants take up a large portion of life—with estimates exceeding 285,000 species—and include many familiar and ubiquitous species including trees, shrubs, cacti, grasses, herbs, ferns, mosses, and green algae. Plants share certain characteristics—unlike animals and fungi, they do not voluntarily move, typically growing in a permanent site, passively absorbing nutrients and energy from their environment. In terms of both their total mass and their importance to other organisms, the green plants dominate ecosystems in both land and freshwater. By harnessing sunlight, they act as the primary sources of energy and food for all life in those ecosystems: green algae in freshwater and land plants on the land.

Usage of the term

The term "plant" has gone through several definitions along history.

Green algae, for instance, were traditionally classified as protists, but recent evidence has moved them into the plants along with the land plants.

Origin and phylogeny

Despite Phylogeny changing many of the concepts of how plants should be classified and what divisions remain, currently plants are informally divided among four main groups 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