– Definition:
– Plants are eukaryotes in the kingdom Plantae.
– They are predominantly photosynthetic, using chloroplasts to produce sugars.
– Parasitic plants exist that do not perform photosynthesis.
– Historically, the plant kingdom included algae and fungi.
– Current definitions exclude fungi and some algae.
– Taxonomic history:
– Aristotle classified living things into plants and animals.
– Linnaeus laid the basis for modern classification systems.
– There are around 382,000 accepted plant species.
– 85-90% of plants are flowering plants.
– Projects like World Flora Online aim to document all plant species.
– Evolutionary history:
– Land plants evolved from aquatic ancestors.
– The first land plants appeared around 450 million years ago.
– Plants diversified in the late Silurian period.
– Basic plant features like roots and leaves were present by the end of the Devonian.
– The Cretaceous period saw a rapid evolution of flowering plants.
– Phylogeny:
– A 2019 phylogeny was proposed based on genomes of 1,153 plant species.
– Algal groups’ placement is supported by genome-based phylogenies.
– Chlorophyte and streptophyte algae are considered paraphyletic.
– Land plants arose from a common ancestor shared with some algal groups.
– Phylogenetic relationships among plant species are continually refined.
– Importance and uses:
– Plants provide a substantial amount of the world’s oxygen.
– They form the basis of many ecosystems and food chains.
– Plants like grains, fruits, and vegetables are essential in human diets.
– People use plants for building materials, medicines, and other purposes.
– The scientific study of plants is known as botany, a branch of biology.
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.
| Plants Temporal range:
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|---|---|
Scientific classification 
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| Domain: | Eukaryota |
| Clade: | Diaphoretickes |
| (unranked): | Archaeplastida |
| Kingdom: | Plantae H.F.Copel., 1956 |
| Superdivisions | |
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see text | |
| Synonyms | |
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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.
English
Etymology
From Middle English plante, from Old English plante (“young tree or shrub, herb newly planted”), from Latin planta (“sprout, shoot, cutting”).
