Plant

Plants are the eukaryotes that form the kingdom Plantae; they are predominantly photosynthetic. This means that they obtain their energy from sunlight, using chloroplasts derived from endosymbiosis with cyanobacteria to produce sugars from carbon dioxide and water, using the green pigment chlorophyll. Exceptions are parasitic plants that have lost the genes for chlorophyll and photosynthesis, and obtain their energy from other plants or fungi.

For other uses, see Plant (disambiguation).

Historically, as in Aristotle's biology, the plant kingdom encompassed all living things that were not animals, and included algae and fungi. Definitions have narrowed since then; current definitions exclude the fungi and some of the algae. By the definition used in this article, plants form the clade Viridiplantae (green plants), which consists of the green algae and the embryophytes or land plants (hornworts, liverworts, mosses, lycophytes, ferns, conifers and other gymnosperms, and flowering plants). A definition based on genomes includes the Viridiplantae, along with the red algae and the glaucophytes, in the clade Archaeplastida.

There are about 380,000 known species of plants, of which the majority, some 260,000, produce seeds. They range in size from single cells to the tallest trees. Green plants provide a substantial proportion of the world's molecular oxygen; the sugars they create supply the energy for most of Earth's ecosystems and other organisms, including animals, either consume plants directly or rely on organisms which do so.

Grain, fruit, and vegetables are basic human foods and have been domesticated for millennia. People use plants for many purposes, such as building materials, ornaments, writing materials, and, in great variety, for medicines. The scientific study of plants is known as botany, a branch of biology.

Cross-section of a stem of Rhynia, an early land plant, preserved in Rhynie chert from the early Devonian

By the Devonian, plants had adapted to land with roots and woody stems.

In the Carboniferous, horsetails such as Asterophyllites proliferated in swampy forests.

Conifers became diverse and often dominant in the Jurassic. Cone of Araucaria mirabilis.

Adaptive radiation in the Cretaceous created many flowering plants, such as Sagaria in the Ranunculaceae.

Bee gathering pollen (orange pollen basket on its leg)

Hummingbird visiting a flower for nectar

Seed dispersal by animals: many hooked Geum urbanum fruits attached to a dog's fur

Legumes have root nodules containing symbiotic Rhizobium nitrogen fixing bacteria.

A sundew leaf with sticky hairs curling to trap and digest a fly

Aquatic plant

Carbon dioxide removal

Ecological succession

Foodscaping

Natural environment

Perennial

Phytoremediation

Plant identification

Plant perception (physiology)

Terrarium

World Environment Day

Evans, L.T. (1998). Feeding the Ten Billion – Plants and Growth. Cambridge University Press.ISBN 0-521-64685-5.

Population

Kenrick, Paul; Crane, Peter R. (1997). The Origin and Early Diversification of Land Plants: A Cladistic Study. Washington, D.C.: . ISBN 1-56098-730-8.

Smithsonian Institution Press

Raven, Peter H.; Evert, Ray F.; Eichhorn, Susan E. (2005). Biology of Plants (7th ed.). New York: . ISBN 0-7167-1007-2.

W.H. Freeman and Company

Taylor, Thomas N.; Taylor, Edith L. (1993). The Biology and Evolution of Fossil Plants. Englewood Cliffs, New Jersey: . ISBN 0-13-651589-4.

Prentice Hall

General:

Species estimates and counts:

Index Nominum Algarum

. Archived 10 February 2006.

Interactive Cronquist classification

. Archived 11 June 2010.

Plant Resources of Tropical Africa

. Archived 9 March 2022 at the Wayback Machine.