Definition:
– Plants are eukaryotes in the kingdom Plantae.
– They are predominantly photosynthetic, using chloroplasts to produce sugars from carbon dioxide and water.
– Exceptions include parasitic plants that do not perform photosynthesis.
– Historically, plants encompassed all non-animal living things, including algae and fungi.
– Current definitions exclude fungi and some algae.
Taxonomic history:
– Aristotle classified living things into plants and animals based on soul characteristics.
– Linnaeus established the modern system of classification, naming the plant kingdom Vegetabilia.
– There are about 380,000 known plant species, with the majority producing seeds.
– Various green plant divisions exist, with flowering plants comprising 85-90%.
– Projects like the 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.
– Plant diversity began in the late Silurian period.
– Basic plant features like roots and leaves emerged by the end of the Devonian period.
– Flowering plants evolved rapidly in the Cretaceous period.
Phylogeny:
– A 2019 phylogeny based on genomes and transcriptomes proposed plant relationships.
– Algal groups support plant classification based on genome analyses.
– Bryophyta classification is backed by genomic studies.
– Plant cells have unique features compared to other eukaryotic cells.
– Land plants originated from chlorophyte and streptophyte algae.
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”).