Plants Fossil range: Cambrian to recent, but see text
Scientific classification
Domain: Eukaryota (unranked) Archaeplastida Kingdom: Plantae Haeckel, 1866[1]
Divisions
Green algae Chlorophyta Charophyta Land plants (embryophytes) Non-vascular land plants (bryophytes) Marchantiophyta—liverworts Anthocerotophyta—hornworts Bryophyta—mosses †Horneophytopsida Vascular plants (tracheophytes) †Rhyniophyta—rhyniophytes †Zosterophyllophyta—zosterophylls Lycopodiophyta—clubmosses †Trimerophytophyta—trimerophytes Pteridophyta—ferns and horsetails †Progymnospermophyta Seed plants (spermatophytes) †Pteridospermatophyta—seed ferns Pinophyta—conifers Cycadophyta—cycads Ginkgophyta—ginkgo Gnetophyta—gnetae Magnoliophyta—flowering plants †Nematophytes

Plants are a major group of life forms and include familiar organisms such as trees, herbs, bushes, grasses, vines, ferns, mosses, and green algae. The Cambrian is a geologic period and system that began about Ma (million years ago at the end of the Proterozoic eon and ended about Ma with Animals Plants fungi, and Protists are eukaryotes (juːˈkærɪɒt or -oʊt Organisms whose cells are organized into complex The Archaeplastida or Primoplantae are a major line of Eukaryotes comprising the land plants green and Red algae and a small Ernst Heinrich Philipp August Haeckel ( February 16, 1834 — August 9, 1919)also written von Haeckel, was an eminent German The green algae (singular green alga) are the large group of Algae from which the Embryophytes (higher plants emerged Chlorophyta, a division of Green algae, of mostly aquatic Photosynthetic Eukaryotic organisms The Charophyta are a division of Green algae, including the closest relatives of the Embryophyte plants The embryophytes are the most familiar group of Plants They include Trees Flowers Ferns Mosses and various other green Bryophytes are all Embryophytes ('land Plants) that are non-vascular: they have tissues and enclosed reproductive systems but they lack Vascular tissue The Marchantiophyta are a division of Bryophyte Plants commonly referred to as hepatics or liverworts. This is an article about the non-vascular plants The name Hornwort is also often applied to an aquatic plant Ceratophyllum demersum in the family Ceratophyllaceae Mosses are small soft Plants that are typically 1–10  cm (0 In Biology and Ecology, extinction is the cessation of existence of a Species or group of taxa. Horneophytopsida is a class of early Vascular plants including the genera Caia, Tortilicaulis, and Horneophyton Vascular plants (also known as tracheophytes or higher plants) are those Plants that have lignified tissues for conducting In Biology and Ecology, extinction is the cessation of existence of a Species or group of taxa. Rhyniophyta is a division of early Vascular plants including the class Rhyniopsida. In Biology and Ecology, extinction is the cessation of existence of a Species or group of taxa. The Zosterophyllaceae or Zosterophylls (class Zosterophyllopsida) were probably Stem-group Lycophytes forming a sister group to the ancestors The Division Lycopodiophyta (sometimes called Lycophyta) is a tracheophyte subdivision of the Kingdom Plantae It is the oldest extant (living In Biology and Ecology, extinction is the cessation of existence of a Species or group of taxa. A division of early land plant from the Devonian containing genera such as Psilophyton. A fern is any one of a group of about 20000 Species of Plants classified in the phylum or division Pteridophyta, also known as Filicophyta In Biology and Ecology, extinction is the cessation of existence of a Species or group of taxa. The spermatophytes (from the Greek word "Σπερματόφυτα" (also known as phanerogams) comprise those Plants that produce Seeds They are In Biology and Ecology, extinction is the cessation of existence of a Species or group of taxa. Pteridospermatophyta, also called seed ferns, is an extinct Spermatophyte group of the Plantae kingdom. Cycads are a group of Seed plants characterized by a large crown of compound leaves and a stout trunk. The Ginkgoaceae is a family of Gymnosperms which appeared during the Mesozoic Era of which the only extant representative is Ginkgo biloba The Plant division Gnetophyta or gnetophytes comprise three related families of Woody plants grouped in the Gymnosperms The gnetophytes differ from The flowering plants or angiosperms ( Angiospermae or Magnoliophyta) are the most widespread group In Biology and Ecology, extinction is the cessation of existence of a Species or group of taxa. The Nematophytes are a group of land organisms probably plants (although their biochemistry is consistent with an algal affnity known only from the Fossil record from Life is a state that distinguishes Organisms from non-living objects such as non-life and dead organisms being manifested by growth through Metabolism A tree is a perennial Woody plant. It is most often defined as a woody plant that has many secondary branches supported clear of the ground on a single main stem or A(n herb (ˈhɝb or /ˈɝb/ see pronunciation differences) is a plant that is valued for qualities such as medicinal properties flavor scent or the like A shrub or Bush is a horticultural rather than strictly botanical category of Woody plant, distinguished from a Tree Poaceae or Gramineae is a family in the Class Liliopsida of the flowering plants. A vine is any plant of Genus Vitis (the Grape plants or by extension any similar climbing or trailing plant A fern is any one of a group of about 20000 Species of Plants classified in the phylum or division Pteridophyta, also known as Filicophyta Mosses are small soft Plants that are typically 1–10  cm (0 The green algae (singular green alga) are the large group of Algae from which the Embryophytes (higher plants emerged About 350,000 species of plants, defined as seed plants, bryophytes, ferns and fern allies, are estimated to exist currently. In Biology, a species is one of the basic units of Biological classification and a Taxonomic rank. The spermatophytes (from the Greek word "Σπερματόφυτα" (also known as phanerogams) comprise those Plants that produce Seeds They are Bryophytes are all Embryophytes ('land Plants) that are non-vascular: they have tissues and enclosed reproductive systems but they lack Vascular tissue A fern is any one of a group of about 20000 Species of Plants classified in the phylum or division Pteridophyta, also known as Filicophyta Fern ally is a general term covering a somewhat diverse group of Vascular plants that are not Flowering plants and not true Ferns Like ferns these plants As of 2004, some 287,655 species had been identified, of which 258,650 are flowering and 18,000 bryophytes (see table below). A flower, also known as a bloom or Blossom, is the reproductive structure found in Flowering plants (plants of the division Magnoliophyta, also Bryophytes are all Embryophytes ('land Plants) that are non-vascular: they have tissues and enclosed reproductive systems but they lack Vascular tissue Green plants, sometimes called metaphytes, obtain most of their energy from sunlight via a process called photosynthesis. Electromagnetic radiation takes the form of self-propagating Waves in a Vacuum or in Matter. Photosynthesis is a Metabolic pathway that converts Light Energy into Chemical energy.

Definition

Aristotle divided all living things between plants (which generally do not move), and animals (which often are mobile to catch their food). Aristotle (Greek Aristotélēs) (384 BC – 322 BC was a Greek philosopher a student of Plato and teacher of Alexander the Great. In Linnaeus' system, these became the Kingdoms Vegetabilia (later Metaphyta or Plantae) and Animalia (also called Metazoa). Carl Linnaeus (Latinized as Carolus Linnaeus, also known after his ennoblement as, May 23 new style (13 May old style 1707 who laid the foundations for In biological Taxonomy, a kingdom or regnum is a Taxonomic rank in either (historically the highest rank or (in the new three-domain system Since then, it has become clear that the Plantae as originally defined included several unrelated groups, and the fungi and several groups of algae were removed to new kingdoms. A fungus (ˈfʌŋgəs is a eukaryotic Organism that is a member of the kingdom Fungi (ˈfʌndʒaɪ Algae ( sing. alga are a large and diverse group of simple typically Autotrophic organisms ranging from Unicellular to Multicellular forms However, these are still often considered plants in many contexts, both technical and popular.

When the name Plantae or plants is applied to a specific taxon, it is usually referring to one of three concepts. From smallest to largest in inclusiveness, these three groupings are:

• Land plants, also known as Embryophyta or Metaphyta. The embryophytes are the most familiar group of Plants They include Trees Flowers Ferns Mosses and various other green As the narrowest of plant categories, this is further delineated below.
• Green plants - also known as Viridiplantae, Viridiphyta or Chlorobionta - comprise the above Embryophytes, Charophyta (i. The Charophyta are a division of Green algae, including the closest relatives of the Embryophyte plants e. , primitive stoneworts), and Chlorophyta (i. The Charales are Algae in the division Charophyta. They are green plants believed to be the closest relatives of the green land plants. Chlorophyta, a division of Green algae, of mostly aquatic Photosynthetic Eukaryotic organisms e. , green algae such as sea lettuce). The green algae (singular green alga) are the large group of Algae from which the Embryophytes (higher plants emerged The sea lettuces comprise the Genus Ulva, a group of edible Green algae widely distributed along the coasts of the world's Oceans It is this clade which is mainly the subject of this article. A clade is a taxonomic group comprising a single Common ancestor and all the descendants of that ancestor
• Archaeplastida - also known as Plantae sensu lato, Plastida or Primoplantae - comprises the green plants above, as well as Rhodophyta (red algae) and Glaucophyta (simple glaucophyte algae). The Archaeplastida or Primoplantae are a major line of Eukaryotes comprising the land plants green and Red algae and a small Sensu is a Latin term meaning "in the sense of"It is used in fields including biology geology and law in the phrases sensu stricto The red algae (Rhodophyta ˌroʊdəˈfaɪtə roʊˈdɒfɨtə from Greek: ῥόδον (rhodon = rose + φυτόν (phyton = plant thus red plant are The glaucophytes, also known as glaucocystophytes or glaucocystids, are a small group of freshwater microscopic Algae. As the broadest plant clade, this comprises most of the eukaryotes that eons ago acquired their chloroplasts directly by engulfing cyanobacteria. Animals Plants fungi, and Protists are eukaryotes (juːˈkærɪɒt or -oʊt Organisms whose cells are organized into complex Chloroplasts are Organelles found in Plant cells and eukaryotic Algae that conduct Photosynthesis. Cyanobacteria, also known as blue-green algae, blue-green bacteria or Cyanophyta, is a phylum of Bacteria that obtain their energy

Informally, other creatures that carry out photosynthesis are called plants as well, but they do not constitute a formal taxon and represent species that are not closely related to true plants. There are around 375,000 species of plants, and each year more are found and described by science.

Algae

Green algae from Ernst Haeckel's Kunstformen der Natur, 1904. The green algae (singular green alga) are the large group of Algae from which the Embryophytes (higher plants emerged Ernst Heinrich Philipp August Haeckel ( February 16, 1834 — August 9, 1919)also written von Haeckel, was an eminent German Kunstformen der Natur ( German: Art Forms of Nature) is a book of lithographic and Autotype prints by German biologist

Main article: Algae

Most algae are no longer classified within the Kingdom Plantae. Algae ( sing. alga are a large and diverse group of simple typically Autotrophic organisms ranging from Unicellular to Multicellular forms Algae ( sing. alga are a large and diverse group of simple typically Autotrophic organisms ranging from Unicellular to Multicellular forms ^[2][3] The algae comprise several different groups of organisms that produce energy through photosynthesis, each of which arose independently from separate non-photosynthetic ancestors. Most conspicuous among the algae are the seaweeds, multicellular algae that may roughly resemble terrestrial plants, but are classified among the green, red, and brown algae. Seaweed is a loose colloquial term encompassing macroscopic Multicellular, benthic marine Algae. The green algae (singular green alga) are the large group of Algae from which the Embryophytes (higher plants emerged The red algae (Rhodophyta ˌroʊdəˈfaɪtə roʊˈdɒfɨtə from Greek: ῥόδον (rhodon = rose + φυτόν (phyton = plant thus red plant are The Phaeophyceae or brown algae, (singular alga is a large group of mostly marine multicellular Algae including many Seaweeds of colder Each of these algal groups also includes various microscopic and single-celled organisms.

Only two groups of algae are considered close relatives of land plants (embryophytes). The embryophytes are the most familiar group of Plants They include Trees Flowers Ferns Mosses and various other green The first of these groups is the Charophyta (desmids and stoneworts), from which the embryophytes developed. The Charophyta are a division of Green algae, including the closest relatives of the Embryophyte plants Desmids are an order ( Desmidiales) of Green algae comprising around 40 genera and 5000 to 6000 Species, found mostly but not exclusively ^[4][5][6] The sister group to the combined embryophytes and charophytes is the other group of green algae (Chlorophyta), and this more inclusive group is collectively referred to as the green plants or Viridiplantae. Cladistics is the hierarchical classification of Species based on evolutionary ancestry Chlorophyta, a division of Green algae, of mostly aquatic Photosynthetic Eukaryotic organisms Plants are living Organisms belonging to the kingdom Plantae. The Kingdom Plantae is often taken to mean this monophyletic grouping. A clade is a taxonomic group comprising a single Common ancestor and all the descendants of that ancestor With a few exceptions among the green algae, all such forms have cell walls containing cellulose, have chloroplasts containing chlorophylls a and b, and store food in the form of starch. Cellulose is an Organic compound with the formula, a Polysaccharide consisting of a linear chain of several hundred to over ten thousand β(1→4 Chloroplasts are Organelles found in Plant cells and eukaryotic Algae that conduct Photosynthesis. Chlorophyll is a green Pigment found in most Plants Algae and Cyanobacteria. Starch, CAS # 9005-25-8 Chemical formula (C6H10O5n is a Polysaccharide They undergo closed mitosis without centrioles, and typically have mitochondria with flat cristae. Mitosis is the process in which a Eukaryotic cell separates the Chromosomes in its Cell nucleus, into two identical sets in two daughter nuclei A Centriole is a barrel shaped Organelle found in most animal Eukaryotic cells though absent in Higher plants and Fungi. In Cell biology, a mitochondrion (plural mitochondria) is a membrane-enclosed Organelle found in most eukaryotic cells.

The chloroplasts of green plants are surrounded by two membranes, suggesting they originated directly from endosymbiotic cyanobacteria. Chloroplasts are Organelles found in Plant cells and eukaryotic Algae that conduct Photosynthesis. Cyanobacteria, also known as blue-green algae, blue-green bacteria or Cyanophyta, is a phylum of Bacteria that obtain their energy The same is true of two additional groups of algae: the Rhodophyta (red algae) and Glaucophyta. The red algae (Rhodophyta ˌroʊdəˈfaɪtə roʊˈdɒfɨtə from Greek: ῥόδον (rhodon = rose + φυτόν (phyton = plant thus red plant are The glaucophytes, also known as glaucocystophytes or glaucocystids, are a small group of freshwater microscopic Algae. All three groups together are generally believed to have a common origin, and so are classified together in the taxon Archaeplastida. The Archaeplastida or Primoplantae are a major line of Eukaryotes comprising the land plants green and Red algae and a small In contrast, most other algae (e. g. heterokonts, haptophytes, dinoflagellates, and euglenids) have chloroplasts with three or four surrounding membranes. The heterokonts or stramenopiles are a major line of Eukaryotes presently containing about 10500 known species The haptophytes, classed either as the Prymnesiophyta or Haptophyta are a Phylum of Algae The Chloroplasts are pigmented similarly to those of the The dinoflagellates are a large group of Flagellate Protists Most are marine Plankton, but The euglenids (or euglenoids) are one of the best-known groups of Flagellates commonly found in freshwater especially when it is rich in organic materials with a They are not close relatives of the green plants, presumably acquiring chloroplasts separately from ingested or symbiotic green and red algae.

Fungi

Main article: Fungi

Fungi are no longer considered to be plants, though they were previously included in the plant kingdom. A fungus (ˈfʌŋgəs is a eukaryotic Organism that is a member of the kingdom Fungi (ˈfʌndʒaɪ A fungus (ˈfʌŋgəs is a eukaryotic Organism that is a member of the kingdom Fungi (ˈfʌndʒaɪ Unlike embryophytes and algae, fungi are not photosynthetic, but are saprotrophs: obtaining food by breaking down and absorbing surrounding materials. Fungi are not plants, but were historically treated as closely related to plants, and were considered to be in the purview of botanists. It has long been recognized that fungi are evolutionarily closer to animals than to plants, but they still are covered more in depth in introductory botany courses and are not necessarily touched upon in introductory zoology courses. Most fungi are formed by microscopic structures called hyphae, which may or may not be divided into cells but contain eukaryotic nuclei. A hypha (plural hyphae) is a long branching filamentous cell of a Fungus, and also of unrelated Actinobacteria. Animals Plants fungi, and Protists are eukaryotes (juːˈkærɪɒt or -oʊt Organisms whose cells are organized into complex In Cell biology, the nucleus (pl nuclei; from Latin la ''nucleus'' or la ''nuculeus'' "little nut" or kernel is a membrane-enclosed Fruiting bodies, of which mushrooms are most familiar, are the reproductive structures of fungi. A mushroom is the fleshy Spore -bearing Fruiting body of a Fungus, typically produced above ground on soil or on its food source They are not related to any of the photosynthetic groups, but are close relatives of animals. Therefore, the fungi are in a kingdom of their own. A fungus (ˈfʌŋgəs is a eukaryotic Organism that is a member of the kingdom Fungi (ˈfʌndʒaɪ

Diversity

About 350,000 species of plants, defined as seed plants, bryophytes, ferns and fern allies, are estimated to exist currently. In Biology, a species is one of the basic units of Biological classification and a Taxonomic rank. The spermatophytes (from the Greek word "Σπερματόφυτα" (also known as phanerogams) comprise those Plants that produce Seeds They are Bryophytes are all Embryophytes ('land Plants) that are non-vascular: they have tissues and enclosed reproductive systems but they lack Vascular tissue A fern is any one of a group of about 20000 Species of Plants classified in the phylum or division Pteridophyta, also known as Filicophyta Fern ally is a general term covering a somewhat diverse group of Vascular plants that are not Flowering plants and not true Ferns Like ferns these plants As of 2004, some 287,655 species had been identified, of which 258,650 are flowering plants, 16,000 bryophytes, 11,000 ferns and 8,000 green algae. The flowering plants or angiosperms ( Angiospermae or Magnoliophyta) are the most widespread group Bryophytes are all Embryophytes ('land Plants) that are non-vascular: they have tissues and enclosed reproductive systems but they lack Vascular tissue A fern is any one of a group of about 20000 Species of Plants classified in the phylum or division Pteridophyta, also known as Filicophyta The green algae (singular green alga) are the large group of Algae from which the Embryophytes (higher plants emerged

Phylogeny

A proposed phylogeny of the Plantae after Kenrick and Crane^[15] is as follows, with modification to the Pteridophyta from Smith et al. The green algae (singular green alga) are the large group of Algae from which the Embryophytes (higher plants emerged Chlorophyta, a division of Green algae, of mostly aquatic Photosynthetic Eukaryotic organisms The green algae (singular green alga) are the large group of Algae from which the Embryophytes (higher plants emerged The Charophyta are a division of Green algae, including the closest relatives of the Embryophyte plants The green algae (singular green alga) are the large group of Algae from which the Embryophytes (higher plants emerged Desmids are an order ( Desmidiales) of Green algae comprising around 40 genera and 5000 to 6000 Species, found mostly but not exclusively Bryophytes are all Embryophytes ('land Plants) that are non-vascular: they have tissues and enclosed reproductive systems but they lack Vascular tissue The Marchantiophyta are a division of Bryophyte Plants commonly referred to as hepatics or liverworts. This is an article about the non-vascular plants The name Hornwort is also often applied to an aquatic plant Ceratophyllum demersum in the family Ceratophyllaceae Mosses are small soft Plants that are typically 1–10  cm (0 The pteridophytes are Vascular plants (plants with Xylem and Phloem) that neither Flower nor produce Seeds hence they are called vascular The Division Lycopodiophyta (sometimes called Lycophyta) is a tracheophyte subdivision of the Kingdom Plantae It is the oldest extant (living A fern is any one of a group of about 20000 Species of Plants classified in the phylum or division Pteridophyta, also known as Filicophyta The spermatophytes (from the Greek word "Σπερματόφυτα" (also known as phanerogams) comprise those Plants that produce Seeds They are Cycads are a group of Seed plants characterized by a large crown of compound leaves and a stout trunk. The Ginkgoaceae is a family of Gymnosperms which appeared during the Mesozoic Era of which the only extant representative is Ginkgo biloba The Plant division Gnetophyta or gnetophytes comprise three related families of Woody plants grouped in the Gymnosperms The gnetophytes differ from The flowering plants or angiosperms ( Angiospermae or Magnoliophyta) are the most widespread group ^[16] The Prasinophyceae may be a paraphyletic basal group to all green plants. In taxonomy, Prasinophytes are a class of primitive Eukaryotic, marine Green algae.

Embryophytes

Main article: Embryophyte

Dicksonia antarctica, a species of tree fern. In taxonomy, Prasinophytes are a class of primitive Eukaryotic, marine Green algae. The embryophytes are the most familiar group of Plants They include Trees Flowers Ferns Mosses and various other green Polysporangiophytes are plants with a structure of branching axes terminating in sporangia. Vascular plants (also known as tracheophytes or higher plants) are those Plants that have lignified tissues for conducting The spermatophytes (from the Greek word "Σπερματόφυτα" (also known as phanerogams) comprise those Plants that produce Seeds They are A fern is any one of a group of about 20000 Species of Plants classified in the phylum or division Pteridophyta, also known as Filicophyta The Pteridopsida is a class of Plants in the Division Pteridophyta that includes all the Leptosporangiate ferns In the recent 2006 classification by Class Marattiopsida is a group of Ferns containing a single order Marattiales, and family Marattiaceae. Equisetopsida, or Sphenopsida, is a class of Plants with a fossil record going back to the Devonian. Psilotopsida is a class of Fern -like plants As circumscribed by Smith et al The cladoxylopsids are a group of Plants known only as Fossils that are thought to be ancestors of Ferns and Horsetails They had a central trunk The Division Lycopodiophyta (sometimes called Lycophyta) is a tracheophyte subdivision of the Kingdom Plantae It is the oldest extant (living The Zosterophyllaceae or Zosterophylls (class Zosterophyllopsida) were probably Stem-group Lycophytes forming a sister group to the ancestors Rhyniophyta is a division of early Vascular plants including the class Rhyniopsida. Aglaophyton major was the Sporophyte generation of Diplohaplontic, pre-vascular axial free-sporing land plant of the Lower Devonian that Horneophytopsida is a class of early Vascular plants including the genera Caia, Tortilicaulis, and Horneophyton Mosses are small soft Plants that are typically 1–10  cm (0 This is an article about the non-vascular plants The name Hornwort is also often applied to an aquatic plant Ceratophyllum demersum in the family Ceratophyllaceae The Marchantiophyta are a division of Bryophyte Plants commonly referred to as hepatics or liverworts. The Charophyta are a division of Green algae, including the closest relatives of the Embryophyte plants Chlorophyta, a division of Green algae, of mostly aquatic Photosynthetic Eukaryotic organisms In taxonomy, the Trebouxiophyceae are a class of Green algae, in the division Chlorophyta The Chlorophyceae are one of the classes of Green algae distinguished mainly on the basis of ultrastructural morphology The Ulvophyceae or Ulvophytes are class of Green algae The embryophytes are the most familiar group of Plants They include Trees Flowers Ferns Mosses and various other green Dicksonia antarctica, known as the Soft Tree Fern Man Fern or Tasmanian Tree Fern is an evergreen Tree fern native to parts of Australia, namely The order Cyatheales is a Taxonomic division of the Fern subclass Cyatheatae, which includes the tree ferns.

Most familiar are the multicellular land plants, called embryophytes. Multicellular organisms are Organisms consisting of more than one cell, and having Differentiated cells that perform specialized functions The embryophytes are the most familiar group of Plants They include Trees Flowers Ferns Mosses and various other green They include the vascular plants, plants with full systems of leaves, stems, and roots. Vascular plants (also known as tracheophytes or higher plants) are those Plants that have lignified tissues for conducting In Botany, a leaf is an above-ground Plant organ specialized for Photosynthesis. A stem is one of two main structural axes of a Vascular plant. ROOT is an object-oriented program and library developed by CERN. They also include a few of their close relatives, often called bryophytes, of which mosses and liverworts are the most common. Bryophytes are all Embryophytes ('land Plants) that are non-vascular: they have tissues and enclosed reproductive systems but they lack Vascular tissue Mosses are small soft Plants that are typically 1–10  cm (0 The Marchantiophyta are a division of Bryophyte Plants commonly referred to as hepatics or liverworts.

All of these plants have eukaryotic cells with cell walls composed of cellulose, and most obtain their energy through photosynthesis, using light and carbon dioxide to synthesize food. Animals Plants fungi, and Protists are eukaryotes (juːˈkærɪɒt or -oʊt Organisms whose cells are organized into complex A cell wall is a tough flexible and sometimes fairly rigid layer surrounding a cell, located external to the Cell membrane, which provides the cell with structural Cellulose is an Organic compound with the formula, a Polysaccharide consisting of a linear chain of several hundred to over ten thousand β(1→4 Photosynthesis is a Metabolic pathway that converts Light Energy into Chemical energy. Light, or visible light, is Electromagnetic radiation of a Wavelength that is visible to the Human eye (about 400–700 Carbon dioxide ( Chemical formula:) is a Chemical compound composed of two Oxygen Atoms covalently bonded to a single About three hundred plant species do not photosynthesize but are parasites on other species of photosynthetic plants. Parasitism is a type of symbiotic relationship between Organisms of different Species. Plants are distinguished from green algae, which represent a mode of photosynthetic life similar to the kind modern plants are believed to have evolved from, by having specialized reproductive organs protected by non-reproductive tissues. The green algae (singular green alga) are the large group of Algae from which the Embryophytes (higher plants emerged

Bryophytes first appeared during the early Palaeozoic. The Paleozoic or Palaeozoic Era (from the Greek palaio (παλαιο "old" and zoe (ζωη "life" meaning "ancient life" They can only survive where moisture is available for significant periods, although some species are desiccation tolerant. Most species of bryophyte remain small throughout their life-cycle. This involves an alternation between two generations: a haploid stage, called the gametophyte, and a diploid stage, called the sporophyte. "Haplo" redirects here For the fictional character see The Death Gate Cycle. In Plants and Algae that undergo Alternation of generations, a gametophyte is the multicellular structure or phase that is Haploid, containing "Haplo" redirects here For the fictional character see The Death Gate Cycle. All land plants and some Algae, have life cycles in which a haploid Gametophyte generation alternates with a Diploid sporophyte, the generation of a The sporophyte is short-lived and remains dependent on its parent gametophyte.

Vascular plants first appeared during the Silurian period, and by the Devonian had diversified and spread into many different land environments. The Silurian is a geologic period and system that extends from the end of the Ordovician period about 443 The Devonian is a geologic period and system of the Paleozoic era spanning from to  million years ago. They have a number of adaptations that allowed them to overcome the limitations of the bryophytes. These include a cuticle resistant to desiccation, and vascular tissues which transport water throughout the organism. In most the sporophyte acts as a separate individual, while the gametophyte remains small.

The first primitive seed plants, Pteridosperms (seed ferns) and Cordaites, both groups now extinct, appeared in the late Devonian and diversified through the Carboniferous, with further evolution through the Permian and Triassic periods. The Permian is a geologic period and system that extends from 299 The Triassic is a geologic period and system that extends from about 251 to 199 Ma (million years ago In these the gametophyte stage is completely reduced, and the sporophyte begins life inside an enclosure called a seed, which develops while on the parent plant, and with fertilisation by means of pollen grains. A seed (in some plants referred to as a kernel) is a small embryonic Plant enclosed in a covering called the seed coat usually with some stored Pollen is a fine to coarse powder consisting of microgametophytes ( pollen grains) which produce the male Gametes (sperm cells of Whereas other vascular plants, such as ferns, reproduce by means of spores and so need moisture to develop, some seed plants can survive and reproduce in extremely arid conditions.

Early seed plants are referred to as gymnosperms (naked seeds), as the seed embryo is not enclosed in a protective structure at pollination, with the pollen landing directly on the embryo. Four surviving groups remain widespread now, particularly the conifers, which are dominant trees in several biomes. A tree is a perennial Woody plant. It is most often defined as a woody plant that has many secondary branches supported clear of the ground on a single main stem or A biome is a climatically and geographically defined area of ecologically similar climatic conditions such as communities of Plants Animals and The angiosperms, comprising the flowering plants, were the last major group of plants to appear, emerging from within the gymnosperms during the Jurassic and diversifying rapidly during the Cretaceous. The flowering plants or angiosperms ( Angiospermae or Magnoliophyta) are the most widespread group The Jurassic is a geologic period and system that extends from about Ma (million years ago to  Ma that is from the end of the Triassic to the beginning The Cretaceous (kriːˈteɪʃəs, usually abbreviated 'K' for its German translation "Kreide" is a geologic period and system, reaching from the end of These differ in that the seed embryo (angiosperm) is enclosed, so the pollen has to grow a tube to penetrate the protective seed coat; they are the predominant group of flora in most biomes today.

Fossils

Main articles: Paleobotany and Evolutionary history of plants

A petrified log in Petrified Forest National Park. Paleobotany, also spelled as palaeobotany (from the Greek words paleon = old and " Botany " study of plants is the branch of Plants have evolved through increasing levels of complexity, from the earliest Algal mats through Bryophytes Lycopods Ferns Petrified Forest National Park is along Interstate 40 between Holbrook and Navajo, in the United States.

Plant fossils include roots, wood, leaves, seeds, fruit, pollen, spores, phytoliths, and amber (the fossilized resin produced by some plants). FOSSIL is a standard protocol for allowing serial communication for Telecommunications programs under the DOS Operating system. Pollen is a fine to coarse powder consisting of microgametophytes ( pollen grains) which produce the male Gametes (sperm cells of In Biology, a spore is a reproductive structure that is adapted for dispersal and surviving for extended periods of time in unfavorable conditions A phytolith ("plant stone" is a rigid microscopic body that occurs in many Plants The most common type of phytolith is the Silicon phytolith also called Amber is Fossil tree Resin, which is appreciated for its color and beauty Fossil land plants are recorded in terrestrial, lacustrine, fluvial and nearshore marine sediments. Pollen, spores and algae (dinoflagellates and acritarchs) are used for dating sedimentary rock sequences. Pollen is a fine to coarse powder consisting of microgametophytes ( pollen grains) which produce the male Gametes (sperm cells of In Biology, a spore is a reproductive structure that is adapted for dispersal and surviving for extended periods of time in unfavorable conditions The dinoflagellates are a large group of Flagellate Protists Most are marine Plankton, but Acritarchs are small organic Fossils present from approximately to the present The remains of fossil plants are not as common as fossil animals, although plant fossils are locally abundant in many regions worldwide.

The earliest fossils clearly assignable to Kingdom Plantae are fossil green algae from the Cambrian. The Cambrian is a geologic period and system that began about Ma (million years ago at the end of the Proterozoic eon and ended about Ma with These fossils resemble calcified multicellular members of the Dasycladales. In Taxonomy, the Dasycladales is an order of large unicellular green algae in the class Ulvophyceae. Earlier Precambrian fossils are known which resemble single-cell green algae, but definitive identity with that group of algae is uncertain. The Precambrian ( Pre-Cambrian) is an informal name for the supereon comprising the eons of the Geologic timescale that came before the current

The oldest known trace fossils of embryophytes date from the Ordovician, though such fossils are fragmentary. Trace fossils, also called ichnofossils (ˈɪknoʊfɒsɨl ιχνος or ikhnos meaning "trace" or "track" are geological records of biological The Ordovician is a geologic period and system, the second of six of the Paleozoic era, and covers the time between 488 By the Silurian, fossils of whole plants are preserved, including the lycophyte Baragwanathia longifolia. The Silurian is a geologic period and system that extends from the end of the Ordovician period about 443 The Division Lycopodiophyta (sometimes called Lycophyta) is a tracheophyte subdivision of the Kingdom Plantae It is the oldest extant (living From the Devonian, detailed fossils of rhyniophytes have been found. Rhyniophyta is a division of early Vascular plants including the class Rhyniopsida. Early fossils of these ancient plants show the individual cells within the plant tissue. The Devonian period also saw the evolution of what many believe to be the first modern tree, Archaeopteris. The Devonian is a geologic period and system of the Paleozoic era spanning from to  million years ago. Archaeopteris is an Extinct genus of tree-like plants with Fern -like leaves This fern-like tree combined a woody trunk with the fronds of a fern, but produced no seeds.

The Coal Measures are a major source of Palaeozoic plant fossils, with many groups of plants in existence at this time. The Coal Measures is a lithostratigraphical term used mainly in the British Isles for the coal-bearing part of the Upper Carboniferous System The Paleozoic or Palaeozoic Era (from the Greek palaio (παλαιο "old" and zoe (ζωη "life" meaning "ancient life" The spoil heaps of coal mines are the best places to collect; coal itself is the remains of fossilised plants, though structural detail of the plant fossils is rarely visible in coal. In the Fossil Forest at Victoria Park in Glasgow, Scotland, the stumps of Lepidodendron trees are found in their original growth positions. Glasgow (ˈglæzgoʊ is the largest city in Scotland and third most populous in the United Kingdom Scotland ( Gaelic: Alba) is a Country in northwest Europethat occupies the northern third of the island of Great Britain. Lepidodendron (also known as the "Scale tree" is an Extinct Genus of primitive vascular arborescent ( Tree -like Plant

The fossilized remains of conifer and angiosperm roots, stems and branches may be locally abundant in lake and inshore sedimentary rocks from the Mesozoic and Caenozoic eras. The Mesozoic Era is one of three geologic eras of the Phanerozoic eon. The Cenozoic (also Caenozoic or Cainozoic) Era (ˌsiːnəˈzoʊɪk/ /ˌsɛn- (meaning "new life" ( Greek ( kainos) "new" Sequoia and its allies, magnolia, oak, and palms are often found. Sequoia sempervirens is the sole living Species of the Genus Sequoia in the cypress family Cupressaceae (formerly Magnolia is a large Genus of about 210 Flowering plant Species in the subclass Magnolioideae of the family The term oak can be used as part of the common name of any of about 400 species of Trees and Shrubs in the Genus Quercus (from Latin Arecaceae or Palmae (also known by the name Palmaceae, which is taxonomically invalid or commonly palm tree) the palm family is a family of Flowering

Petrified wood is common in some parts of the world, and is most frequently found in arid or desert areas where it is more readily exposed by erosion. Petrified wood (from the Greek root "petro" meaning "rock" or "stone" literally "wood turned into stone" is a type of Fossil: it Erosion is the carrying away or displacement of solids ( Sediment, Soil, rock and other particles usually by the agents of currents such as wind Petrified wood is often heavily silicified (the organic material replaced by silicon dioxide), and the impregnated tissue is often preserved in fine detail. The Chemical compound silicon dioxide, also known as silica or silox (from the Latin " Silex " is an Oxide Such specimens may be cut and polished using lapidary equipment. A lapidary (the word means "concerned with stones" is an Artisan who practices the craft of working forming and finishing stone, Mineral, Fossil forests of petrified wood have been found in all continents.

Fossils of seed ferns such as Glossopteris are widely distributed throughout several continents of the southern hemisphere, a fact that gave support to Alfred Wegener's early ideas regarding Continental drift theory. Glossopteris ( Greek glossa (γλώσσα meaning "tongue" because the leaves were tongue-shaped is the largest and best-known Genus Southern Hemisphere is the half of a Planet that is South of the Equator —the word hemisphere literally means 'half ball' Alfred Lothar Wegener ( November 1, 1880 – November 2 or 3 1930 was a German Scientist and Meteorologist. Continental drift is the movement of the Earth 's Continents relative to each other

Life processes

Growth

Most of the solid material in a plant is taken from the atmosphere. Through a process known as photosynthesis, plants use the energy in sunlight to convert carbon dioxide from the atmosphere into simple sugars. Photosynthesis is a Metabolic pathway that converts Light Energy into Chemical energy. Sunlight, in the broad sense is the total spectrum of the Electromagnetic radiation given off by the Sun. Sugar is a class of edible Crystalline substances mainly Sucrose, Lactose, and Fructose. These sugars are then used as building blocks and form the main structural component of the plant. Plants rely on soil primarily for support and water (in quantitative terms), but also obtain nitrogen, phosphorus and other crucial elemental nutrients. Nitrogen (ˈnaɪtɹəʤɪn is a Chemical element that has the symbol N and Atomic number 7 and Atomic weight 14 Phosphorus, (ˈfɒsfərəs is the Chemical element that has the symbol P and Atomic number 15 For the majority of plants to grow successfully they also require oxygen in the atmosphere and around their roots for respiration. However, a few specialized vascular plants, such as Mangroves, can grow with their roots in anoxic conditions. Mangroves (generally are Trees and Shrubs that grow in saline coastal habitats in the Tropics and Subtropics.

The leaf is the primary site of photosynthesis in plants. In Botany, a leaf is an above-ground Plant organ specialized for Photosynthesis. Photosynthesis is a Metabolic pathway that converts Light Energy into Chemical energy.

Factors affecting growth

The genotype of a plant affects its growth, for example selected varieties of wheat grow rapidly, maturing within 110 days, whereas others, in the same environmental conditions, grow more slowly and mature within 155 days. ^[17]

Growth is also determined by environmental factors, such as temperature, available water, available light, and available nutrients in the soil. Temperature is a physical property of a system that underlies the common notions of hot and cold something that is hotter generally has the greater temperature Water is a common Chemical substance that is essential for the survival of all known forms of Life. Light, or visible light, is Electromagnetic radiation of a Wavelength that is visible to the Human eye (about 400–700 A nutrient is food or chemicals that an organism needs to live and grow or a substance used in an organism's metabolism which must be taken in from its environment Any change in the availability of these external conditions will be reflected in the plants growth.

Biotic factors (living organisms) also affect plant growth.

• Plants compete with other plants for space, water, light and nutrients. Plants can be so crowded that no single individual makes normal growth. ^[17]
• Many plants rely on birds and insects to effect pollination.
• Grazing animals may affect vegetation.
• Soil fertility is influenced by the activity of bacteria and fungi.
• Bacteria, fungi, viruses, nematodes and insects can parasitise plants.
• Some plant roots require an association with fungi to maintain normal activity (mycorrhizal association). ^[17]

Simple plants like algae may have short life spans as individuals, but their populations are commonly seasonal. Other plants may be organized according to their seasonal growth pattern:

• Annual: live and reproduce within one growing season. Botanically an annual plant is a Plant that usually germinates, Flowers and dies in one Year.
• Biennial: live for two growing seasons; usually reproduce in second year. A biennial plant is a flowering Plant that takes two years to complete its lifecycle.
• Perennial: live for many growing seasons; continue to reproduce once mature. A perennial plant or perennial ( Latin per, "through" annus, "year" is a Plant that lives for more than

Among the vascular plants, perennials include both evergreens that keep their leaves the entire year, and deciduous plants which lose their leaves for some part of it. In Botany, an Evergreen plant is a plant having leaves all year round Botany Autumn leaf color. See --> In Botany and Horticulture, deciduous Plants, including In temperate and boreal climates, they generally lose their leaves during the winter; many tropical plants lose their leaves during the dry season. The Tropics are centered on the Equator and limited in Latitude by the Tropic of Cancer in the northern hemisphere at approximately 23°26' (23

The growth rate of plants is extremely variable. Some mosses grow less than 0. 001 mm/h, while most trees grow 0. 025-0. 250 mm/h. Some climbing species, such as kudzu, which do not need to produce thick supportive tissue, may grow up to 12. Pueraria lobata (syn P montana P thunbergiana) (sometimes known as foot a night vine, mile a minute vine, Gat Gun, Ge Gan and 5 mm/h.

Plants protect themselves from frost and dehydration stress with antifreeze proteins, heat-shock proteins and sugars (sucrose is common). Frost is the solid deposition of Water vapor from saturated air Dehydration ( hypohydration) is the removal of Water ( hydro in ancient Greek) from an object Antifreeze proteins (AFPs or ice structuring proteins (ISPs refer to a class of Polypeptides produced by certain vertebrates plants fungi and bacteria that permit Heat shock proteins ( HSP) are a group of Proteins whose expression is increased when the cells are exposed to elevated temperatures or other stress Solubility of Pure SucroseTemperature(Cg LEA (Late Embryogenesis Abundant) protein expression is induced by stresses and protects other proteins from aggregation as a result of desiccation and freezing. Embryogenesis is the process by which the Embryo is formed and develops Desiccation is the state of extreme dryness or the process of extreme drying For freezing as a method of food preservation see Frozen food. ^[18]

Internal distribution

Vascular plants differ from other plants in that they transport nutrients between different parts through specialized structures, called xylem and phloem. Vascular plants (also known as tracheophytes or higher plants) are those Plants that have lignified tissues for conducting In Vascular plants xylem is one of the two types of transport tissue Phloem being the other In Vascular plants phloem is the living tissue that carries organic Nutrients (known as photosynthate particularly Sucrose, a sugar to They also have roots for taking up water and minerals. ROOT is an object-oriented program and library developed by CERN. The xylem moves water and minerals from the root to the rest of the plant, and the phloem provides the roots with sugars and other nutrient produced by the leaves. ^[19]

Ecology

The photosynthesis conducted by land plants and algae is the ultimate source of energy and organic material in nearly all ecosystems. Photosynthesis is a Metabolic pathway that converts Light Energy into Chemical energy. Photosynthesis radically changed the composition of the early Earth's atmosphere, which as a result is now 21% oxygen. Oxygen (from the Greek roots ὀξύς (oxys (acid literally "sharp" from the taste of acids and -γενής (-genēs (producer literally begetteris the Animals and most other organisms are aerobic, relying on oxygen; those that do not are confined to relatively rare anaerobic environments. An aerobic organism or aerobe is an Organism that has an Oxygen based Metabolism. For other uses of the term "hypoxia" see Hypoxia. Hypoxia or oxygen depletion is a phenomenon that occurs in aquatic environments Plants are the primary producers in most terrestrial ecosystems and form the basis of the food web in those ecosystems. An autotroph (from the Greek autos = self and trophe = nutrition is an Organism that produces complex Organic compounds from simple Food chains, also called food networks and/or trophic networks, describe the feeding relationships between species within an Ecosystem. Many animals rely on plants for shelter as well as oxygen and food.

Land plants are key components of the water cycle and several other biogeochemical cycles. The Earth 's Water is always in movement and the water cycle, also known as the hydrologic cycle, describes the continuous movement of water on above In Ecology and Earth science, a biogeochemical cycle is a circuit or pathway by which a Chemical element or Molecule moves through both biotic Some plants have coevolved with nitrogen fixing bacteria, making plants an important part of the nitrogen cycle. In a broad sense biological co-evolution is "the change of a biological object triggered by the change of a related object" Nitrogen fixation is the process by which Nitrogen is taken from its natural relatively inert molecular form (N2 in the atmosphere and converted into The nitrogen cycle is the Biogeochemical cycle that describes the transformations of Nitrogen and nitrogen-containing compounds in nature Plant roots play an essential role in soil development and prevention of soil erosion. Soil, often typeset as SOiL, is a four piece rock band from Chicago Illinois United States founded by Shaun Glass Tom Schofield Tim King and Adam Zadel Erosion is the carrying away or displacement of solids ( Sediment, Soil, rock and other particles usually by the agents of currents such as wind

Distribution

Plants are distributed worldwide in varying numbers. While they inhabit a multitude of biomes and ecoregions, few can be found beyond the tundras at the northernmost regions of continental shelves. A biome is a climatically and geographically defined area of ecologically similar climatic conditions such as communities of Plants Animals and An ecoregion ( ecological region) sometimes called a bioregion, is an ecologically and geographically defined area smaller than a "realm" or " In physical Geography, tundra is an area where the Tree growth is hindered by low temperatures and short growing seasons The continental shelf is the extended perimeter of each Continent and associated Coastal plain, which is covered during interglacial periods such At the southern extremes, plants have adapted tenaciously to the prevailing conditions. (See Antarctic flora. Antarctic flora is a distinct community of Vascular plants which evolved millions of years ago on the supercontinent of Gondwana, and is now found on several separate )

Plants are often the dominant physical and structural component of habitats where they occur. Many of the Earth's biomes are named for the type of vegetation because plants are the dominant organisms in those biomes, such as grasslands and forests. A biome is a climatically and geographically defined area of ecologically similar climatic conditions such as communities of Plants Animals and Grasslands (also called greenswards) are areas where the Vegetation is dominated by Grasses ( Poaceae) and other Herbaceous (non-woody A forest is an area with a high density of Trees There are many definitions of a forest based on various criteria

Ecological relationships

The Venus flytrap, a species of carnivorous plant. The Venus Flytrap Dionaea muscipula, is a Carnivorous plant that catches and digests animal prey&mdashmostly Insects and Arachnids Carnivorous plants (sometimes called insectivorous plants) are Plants that derive some or most of their Nutrients (but not Energy) from trapping

Numerous animals have coevolved with plants. Many animals pollinate flowers in exchange for food in the form of pollen or nectar. Pollination in angiosperms and Gymnosperms is the process that transfers pollen grains, which contain the male Gametes (sperm to where the female A flower, also known as a bloom or Blossom, is the reproductive structure found in Flowering plants (plants of the division Magnoliophyta, also Nectar is a Sugar -rich liquid produced by plants It is produced either by the Flowers in which it attracts pollinating animals or by extrafloral Many animals disperse seeds, often by eating fruit and passing the seeds in their feces. Biological dispersal refers to those processes by which a Species maintains ecosystem The term fruit has different meanings dependent on context and the term is not synonymous in Food preparation and Biology. Feces, faeces, or fæces (see spelling differences) is a waste product from an animal's digestive tract expelled through the Anus Myrmecophytes are plants that have coevolved with ants. A myrmecophyte or ant plant is a Plant that lives in association with a colony of Ants and possesses specialized organs in which the ants live Ants are social Insects of the family Formicidae and along with the related families of Wasps and Bees belong to the order The plant provides a home, and sometimes food, for the ants. In exchange, the ants defend the plant from herbivores and sometimes competing plants. Herbivory is a form of Predation in which an Organism, known as a herbivore, consumes principally Autotrophs ref name=Campbell>Campbell Ant wastes provide organic fertilizer. Fertilizers ( also spelt fertiliser are chemical compounds given to Plants to promote growth they are usually applied either through the soil for uptake by plant

The majority of plant species have various kinds of fungi associated with their root systems in a kind of mutualistic symbiosis known as mycorrhiza. Mutualism is a Biological interaction between individuals of two different Species, where both individuals derive a fitness benefit for example increased This article is about the biological phenomenon for other uses see Symbiosis (disambiguation The term symbiosis (from the Greek A mycorrhiza (Greek for fungus roots coined by Frank 1885 typically seen in the plural forms mycorrhizae or mycorrhizas) is a symbiotic (occasionally The fungi help the plants gain water and mineral nutrients from the soil, while the plant gives the fungi carbohydrates manufactured in photosynthesis. Some plants serve as homes for endophytic fungi that protect the plant from herbivores by producing toxins. An endophyte is an Endosymbiont, often a Bacterium or Fungus, that lives within a Plant for at least part of its life without causing apparent The fungal endophyte, Neotyphodium coenophialum, in tall fescue (Festuca arundinacea) does tremendous economic damage to the cattle industry in the U. Neotyphodium coenophialum is a systemic and seed-transmissible Symbiont (endophyte of Lolium arundinaceum (= Festuca arundinacea; tall Fescue Festuca arundinacea is a species of Fescue known by the common name tall fescue. S.

Various forms of parasitism are also fairly common among plants, from the semi-parasitic mistletoe that merely takes some nutrients from its host, but still has photosynthetic leaves, to the fully parasitic broomrape and toothwort that acquire all their nutrients through connections to the roots of other plants, and so have no chlorophyll. Mistletoe is the common name for a group of hemi-parasitic Plants in the order Santalales that grow attached to and within the Broomrape or Broom-rape ( Orobanche) is a genus of about 150 species of parasitic herbaceous plants in the family Orobanchaceae Toothwort ( Lathraea) is a small genus of five to seven species of Flowering plants native to temperate Europe and Asia. Chlorophyll is a green Pigment found in most Plants Algae and Cyanobacteria. Some plants, known as myco-heterotrophs, parasitize mycorrhizal fungi, and hence act as epiparasites on other plants. Myco-heterotrophy is a Symbiotic relationship between certain kinds of Plants and Fungi, in which the plant gets all or part of its food from Parasitism is a type of symbiotic relationship between Organisms of different Species.

Many plants are epiphytes, meaning they grow on other plants, usually trees, without parasitizing them. An epiphyte is an organism that grows upon or attaches to a living plant Epiphytes may indirectly harm their host plant by intercepting mineral nutrients and light that the host would otherwise receive. The weight of large numbers of epiphytes may break tree limbs. Many orchids, bromeliads, ferns and mosses often grow as epiphytes. A fern is any one of a group of about 20000 Species of Plants classified in the phylum or division Pteridophyta, also known as Filicophyta Mosses are small soft Plants that are typically 1–10  cm (0 Bromeliad epiphytes accumulate water in leaf axils to form phytotelmata, complex aquatic food webs. ^[20]

A few plants are carnivorous, such as the Venus flytrap and sundew. Carnivorous plants (sometimes called insectivorous plants) are Plants that derive some or most of their Nutrients (but not Energy) from trapping The Venus Flytrap Dionaea muscipula, is a Carnivorous plant that catches and digests animal prey&mdashmostly Insects and Arachnids The Sundews ( Drosera) comprise one of the largest genera of Carnivorous plants with over 170 Species. They trap small animals and digest them to obtain mineral nutrients, especially nitrogen. Nitrogen (ˈnaɪtɹəʤɪn is a Chemical element that has the symbol N and Atomic number 7 and Atomic weight 14

Importance

Potato plant. The potato is a Starchy Tuberous crop Vegetable from the perennial Solanum tuberosum of the Solanaceae Potatoes spread to the rest of the world after European contact with the Americas in the late 1400s and early 1500s and have since become an important field crop.

Timber in storage for later processing at a sawmill. Lumber or timber is Wood in any of its stages from felling through readiness for use as structural Material for Construction, or A sawmill is a facility where logs are cut into boards Sawmill process A sawmill's basic operation is much like those of 100 years ago a log enters

A section of a Yew branch showing 27 annual growth rings, pale sapwood and dark heartwood, and pith (centre dark spot). Taxus is a Genus of yews small coniferous Trees or Shrubs in the yew family Taxaceae. Pith is a light substance that is found in Vascular plants It consists of soft spongy Parenchyma cells and is located in the center of the stem. The dark radial lines are small knots.

The study of plant uses by people is termed economic botany or ethnobotany. Ethnobotany ( from " ethnology " - study of culture and " Botany " - study of plants) is the scientific study of the relationships They are often used as synonyms but some consider economic botany to focus mainly on uses of modern cultivated plants, while ethnobotany studies uses of indigenous plants by native peoples. Human cultivation of plants is part of agriculture, which is the basis of human civilization. Agriculture refers to the production of goods through the growing of plants and fungi and the raising of domesticated Animals The study of agriculture Plant agriculture is subdivided into agronomy, horticulture and forestry. Agronomy is the science and technology of using plants for food fuel feed and fiber Horticulture is the art and science of plant cultivation Horticulturists (or horticuluralists) work and conduct research in the fields of Plant propagation Forestry is the Art and Science of managing forests tree Plantations and related Natural resources.

Food

Virtually all human nutrition depends on land plants directly or indirectly. Much of human nutrition depends on cereals, especially maize or corn, wheat and rice or other staple crops such as potato, cassava, and legumes. Maize (ˈmeɪz ( Zea mays L. ssp mays) known as corn in some countries is a cereal grain domesticated in Mesoamerica Wheat ( Triticum spp is a worldwide cultivated grass from the Levant area of the Middle East. Rice is a Cereal foodstuff which forms an important part of the diet of many people worldwide and as such it is a staple food for many A staple food is a Food that forms the basis of a Traditional diet. The potato is a Starchy Tuberous crop Vegetable from the perennial Solanum tuberosum of the Solanaceae The cassava, yuca, manioc, or mandioca ( Manihot esculenta) is a woody Shrub of the Euphorbiaceae (spurge family native A legume is a Plant in the family Fabaceae (or Leguminosae or a Fruit of these specific plants Other parts from plants that are eaten include fruits, vegetables, nuts, herbs, spices and edible flowers. The term fruit has different meanings dependent on context and the term is not synonymous in Food preparation and Biology. The term " vegetable " generally means the edible parts of Plants The definition of the word is traditional rather than Scientific, however Nut is a general term for the large dry oily Seeds or Fruit of some Plants. A(n herb (ˈhɝb or /ˈɝb/ see pronunciation differences) is a plant that is valued for qualities such as medicinal properties flavor scent or the like A spice is a dried Seed, Fruit, Root, Bark or vegetative substance used in Nutritionally insignificant quantities as a Food additive A flower, also known as a bloom or Blossom, is the reproductive structure found in Flowering plants (plants of the division Magnoliophyta, also Beverages from plants include coffee, tea, wine, beer and alcohol. CoFFEE is an Open source Software for computer supported collaborative learning (CSCL in a digital classroom Tea refers to the cured agricultural product of the leaves leaf buds and internodes of Camellia sinensis, which have been prepared and cured for the market Wine is an Alcoholic beverage made from the fermentation of Grape juice Beer is the world's oldest and most widely consumed Alcoholic beverage and the third most popular drink overall after water and tea In Chemistry, an alcohol is any Organic compound in which a Hydroxyl group ( - O[[hydrogen H]]) is bound to a Carbon Sugar is obtained mainly from sugar cane and sugar beet. Sugar is a class of edible Crystalline substances mainly Sucrose, Lactose, and Fructose. Sugarcane ( Saccharum) is a genus of 6 to 37 species (depending on taxonomic interpretation of tall perennial grasses (family Poaceae tribe Andropogoneae Sugar beet ( Beta vulgaris L a member of the Chenopodiaceae family is a plant whose root contains a high concentration of Sucrose. Cooking oils and margarine come from corn, soybean, canola, safflower, sunflower, olive and others. Cooking oil is purified Fat of Plant or Animal origin which is liquid at room temperature Margarine (ˈmɑrdʒərɨn /ˈmɑrdʒəriːn/ or /ˈmɑrgəriːn/ as a generic term can indicate any of a wide range of Butter substitutes Canola is a type of Edible oil derived from plants initially bred in Canada by Keith Downey and Baldur Stefansson in the 1970s Safflower ( Carthamus tinctorius L) is a highly branched Herbaceous, Thistle -like annual usually with many long sharp spines on the leaves The sunflower ( Helianthus annuus) is an Annual plant in the family Asteraceae and native to the Americas, with a large flowering The Olive ( Olea europaea) is a Species of small Tree in the family Oleaceae, native to the coastal areas of the eastern Food additives include gum arabic, guar gum, locust bean gum, starch and pectin. Food additives are substances added to food to preserve flavour or improve its taste and appearance Gum arabic, a Natural gum also called gum acacia, and chaar gund or char goond (in India is the hardened Sap taken from two species Guar gum, also called guaran, is a Galactomannan. It is primarily the ground Endosperm of Guar beans The guar seeds are dehusked milled Locust bean gum (also known as carob gum, carob bean gum, carobin, E410) is a Galactomannan vegetable Gum Starch, CAS # 9005-25-8 Chemical formula (C6H10O5n is a Polysaccharide Pectin (from Greek πηκτικός - pektikos, "congealed curdled" a white to light brown powder is a Heteropolysaccharide

Nonfood products

Wood is used for buildings, furniture, paper, cardboard, musical instruments and sports equipment. Wood is hard fibrous lignified structural tissue produced as secondary Xylem in the stems of Woody plants notably trees but also shrubs Cloth is often made from cotton, flax or synthetic fibers derived from cellulose, such as rayon and acetate. Cotton is a soft staple Fibre that grows around the seeds of the cotton plant ( Gossypium sp Flax (also known as common flax or linseed) (binomial name Linum usitatissimum) is a member of the genus Linum Cellulose is an Organic compound with the formula, a Polysaccharide consisting of a linear chain of several hundred to over ten thousand β(1→4 Rayon is a manufactured regenerated cellulosic Fiber. Rayon is produced from naturally occurring Polymers and therefore it is not a truly An acetate, or ethanoate, is either a salt or Ester of Acetic acid. Renewable fuels from plants include firewood, peat and many other biofuels. Firewood was the primary source of fuel until the 1800s when it was displaced by coal and later by oil Peat is an accumulation of partially Decayed Vegetation matter. Coal and petroleum are fossil fuels derived from plants. Petroleum ( L petroleum, from Greek πετρέλαιον, lit Medicines derived from plants include aspirin, taxol, morphine, quinine, reserpine, colchicine, digitalis and vincristine. Aspirin, or acetylsalicylic acid (ASA (əˌsɛtɨlsælɨˌsɪlɨk ˈæsɨd is a Salicylate drug, often used as an Analgesic to relieve Paclitaxel is a Mitotic inhibitor used in Cancer Chemotherapy. Medical uses Morphine can be used as an analgesic in hospital settings to relieve pain in Myocardial infarction pain in Quinine (ˈkwaɪnaɪn kwɪˈniːn ˈkwiːniːn is a natural white Crystalline Alkaloid having Antipyretic (fever-reducing antimalarial, Reserpine is an Indole Alkaloid Antipsychotic and Antihypertensive drug that has been used for the control of high blood pressure Colchicine is a highly poisonous Natural product and Secondary metabolite, originally extracted from plants of the genus Colchicum ( Autumn Vincristine (brand name Oncovin also known as leurocristine, is a vinca Alkaloid from the Madagascar periwinkle ( Catharanthus roseus, There are hundreds of herbal supplements such as ginkgo, Echinacea, feverfew, and Saint John's wort. Ginkgo is a genus of highly unusual non-flowering plants with one extant species G Echinacea, commonly called Purple Coneflower, is a genus of nine species of Herbaceous plants in the family Asteraceae. Feverfew ( Tanacetum parthenium; syn Chrysanthemum parthenium ( L St John's wort (pronounced) used alone refers to the species Hypericum perforatum, also known as Tipton's Weed or Klamath weed, but with qualifiers is Pesticides derived from plants include nicotine, rotenone, strychnine and pyrethrins. A pesticide is a substance or mixture of substances used to kill a pest. Nicotine is an Alkaloid found in the Nightshade family of plants ( Solanaceae) which constitutes approximately 0 Rotenone is an odorless chemical that is used as a broad-spectrum Insecticide, Piscicide, and Pesticide. Strychnine (ˈstrɪkniːn (British US /-naɪn/ or /-nɪn/ (US The pyrethrins are a pair of natural Organic compounds that have potent insecticidal activity Drugs obtained from plants include opium, cocaine and marijuana. Opium is a Narcotic formed from the Latex (ie sap released by lacerating (or "scoring" the immature seed pods of opium poppies ( Cocaine ( benzoylmethyl ecgonine) is a Crystalline Tropane Alkaloid that is obtained from the leaves of the Coca plant Cannabis, also known as marijuana or marihuana, or ganja (from Hindi / Sanskrit: गांजा gānjā hemp) is a Poisons from plants include ricin, hemlock and curare. Ricin (ˈraɪ sɨn is a Protein Toxin that is extracted from the castor bean ( Ricinus communis) Poison hemlock redirects here For other uses of "hemlock" see Hemlock. Curare ''rah'' ree is a common name for various Arrow poisons originating from South America Plants are the source of many natural products such as fibers, essential oils, dyes, pigments, waxes, tannins, latex, gums, resins, alkaloids, amber and cork. Products derived from plants include soaps, paints, shampoos, perfumes, cosmetics, turpentine, rubber, varnish, lubricants, linoleum, plastics, inks, chewing gum and hemp rope. Plants are also a primary source of basic chemicals for the industrial synthesis of a vast array of organic chemicals. A chemical substance is a Material with a definite chemical composition. These chemicals are used in a vast variety of studies and experiments.

Aesthetic uses

Thousands of plant species are cultivated to beautify the human environment as well as to provide shade, modify temperatures, reduce windspeed, abate noise, provide privacy and prevent soil erosion. People use cut flowers, dried flowers and house plants indoors. Outdoors, they use lawngrasses, shade trees, ornamental trees, shrubs, vines, herbaceous perennials and bedding plants. Images of plants are often used in art, architecture, humor, language and photography and on textiles, money, stamps, flags and coats of arms. The language of flowers, sometimes called floriography, was a Victorian-era means of Communication in which various Flowers and floral arrangements Living plant art forms include topiary, bonsai, ikebana and espalier. Topiary is the art of creating Sculptures in the medium of clipped Trees, Shrubs and Sub-shrubs The word derives from the Latin Bonsai (盆栽 literally "potted plant" is the art of Aesthetic miniaturization of Trees by growing them in containers is the Japanese art of Flower arrangement, also known as. Ikebana is the Japanese art of flower arrangement Espalier is the horticultural technique of training trees through pruning and Grafting in order to create formal "two-dimensional" or single plane patterns Ornamental plants have sometimes changed the course of history, as in tulipomania. Ornamental plants are typically grown in the flower Garden or as House plants Most commonly they are grown for the display of their Flowers Other common Tulip mania or tulipomania ( Dutch names include tulpenmanie tulpomanie tulpenwoede tulpengekte and bollengekte) was a period in the Plants are the basis of a multi-billion dollar per year tourism industry which includes travel to arboretums, botanical gardens, historic gardens, national parks, tulip festivals, rainforests, forests with colorful autumn leaves and the National Cherry Blossom Festival. An arboretum is a collection of trees Related collections include a fruticetum (from the Latin frutex, meaning shrub and a viticetum a collection of vines Botanical gardens grow a wide variety of Plants primarily to categorize and document for scientific purposes Garden tourism is a type of niche tourism involving visits or travel to Botanical gardens and places which are significant in the History of gardening. A national park is a reserve of land usually declared and owned by a national Government, protected from most Human development and pollution The Tulip Festivals are held in several North American cities most often ones with Dutch heritage including Albany New York; Ottawa, Ontario Rainforests are Forests characterized by high Rainfall with definitions setting minimum normal annual rainfall between 1750–2000 mm (68-78 inches A forest is an area with a high density of Trees There are many definitions of a forest based on various criteria The National Cherry Blossom Festival is a spring celebration in Washington D Venus flytrap, sensitive plant and resurrection plant are examples of plants sold as novelties. Mimosa pudica ( Sensitive Plant) ( pudica = shy is a creeping annual or perennial Herb often grown for its curiosity value the compound

Scientific and cultural uses

Tree rings are an important method of dating in archeology and serve as a record of past climates. Dendrochronology (from Greek grc δένδρον dendron, "tree" grc χρόνος khronos, "time" and grc -λογία Basic biological research has often been done with plants, such as the pea plants used to derive Gregor Mendel's laws of genetics. Gregor Johann Mendel ( July 20, 1822 &ndash January 6, 1884) was Space stations or space colonies may one day rely on plants for life support. Controlled (or Closed) Ecological Life Support Systems (acronym CELSS) are a type of scientific endeavor to create a self-supporting Life support Plants are used as national and state emblems, including state trees and state flowers. This article is about symbols of nations Many countries it can be used for is Chantal This List of US state trees includes official trees of the following states and U This is a list of US state flowers: See also List of US state trees Lists of U Ancient trees are revered and many are famous. The following is a partial list of trees of significance in history religion size or age Numerous world records are held by plants. Plants are often used as memorials, gifts and to mark special occasions such as births, deaths, weddings and holidays. Plants figure prominently in mythology, religion and literature. Trees have played an important role in many of the world's mythologies and Religions and have been given deep and sacred meanings throughout the ages Fictional plants are plants that have been invented and do not exist in real life The field of ethnobotany studies plant use by indigenous cultures which helps to conserve endangered species as well as discover new medicinal plants. Ethnobotany ( from " ethnology " - study of culture and " Botany " - study of plants) is the scientific study of the relationships Herbalism is a traditional Medicinal or Folk medicine practice based on the use of Plants and Plant extracts Herbalism is also known as Gardening is the most popular leisure activity in the U. Gardening is the practice of growing Plants for their attractive flowers or foliage and Vegetables or Fruits for consumption S. Working with plants or horticulture therapy is beneficial for rehabilitating people with disabilities. Horticultural therapy is the practice of Horticulture as therapy to improve human well-being Certain plants contain psychotropic chemicals which are extracted and ingested, including tobacco, cannabis (marijuana), and opium. Tobacco is an Agricultural product recognized as an addictive drug processed from the fresh Leaves of plants in the genus Nicotiana. Cannabis, also known as marijuana or marihuana, or ganja (from Hindi / Sanskrit: गांजा gānjā hemp) is a Opium is a Narcotic formed from the Latex (ie sap released by lacerating (or "scoring" the immature seed pods of opium poppies (

Negative effects

Weeds are plants that grow where people do not want them. WEED (1390 AM) is a Radio station broadcasting a Spanish format People have spread plants beyond their native ranges and some of these introduced plants become invasive, damaging existing ecosystems by displacing native species. Introduced species|Weed Invasive species is a phrase with several definitions Invasive plants cause billions of dollars in crop losses annually by displacing crop plants, they increase the cost of production and the use of chemical means to control them affects the environment.

Plants may cause harm to people. Plants that produce windblown pollen invoke allergic reactions in people who suffer from hay fever. Hay Fever is a comic play written by Noel Coward in 1924 and first produced in 1925 with Marie Tempest as the first Judith Bliss A wide variety of plants are poisonous. This is a list of Plants containing Poisonous parts that pose a serious risk of illness, injury or Death to Humans or Animals. Several plants cause skin irritations when touched, such as poison ivy. Certain plants contain psychotropic chemicals, which are extracted and ingested or smoked, including tobacco, cannabis (marijuana), cocaine and opium, causing damage to health or even death. A psychoactive drug or psychotropic substance is a Chemical substance that acts primarily upon the Central nervous system where it alters Brain Secondary metabolites are Organic compounds that are not directly involved in the normal growth, development or Reproduction of Organisms Cocaine ( benzoylmethyl ecgonine) is a Crystalline Tropane Alkaloid that is obtained from the leaves of the Coca plant Opium is a Narcotic formed from the Latex (ie sap released by lacerating (or "scoring" the immature seed pods of opium poppies ( ^[21][22] Both illegal and legal drugs derived from plants have negative effects on the economy, affecting worker productivity and law enforcement costs. ^[23][24] Some plants cause allergic reactions in people and animals when ingested, while other plants cause food intolerances that negatively affect health.

See also

• Biosphere
• Botany
• Evolutionary history of plants
• Flower
• Forest
• Fruit
• Garden
• Gardening
• Greenhouse
• Houseplant
• List of poisonous plants
• Paleobotany
• Photosynthesis
• Plant cell
• Plant defense against herbivory
• Plant perception (paranormal)
• Plant perception (physiology)
• Rapid plant movement
• Tree
• Vegetable
• Vegetation
• Phytopathology

References

Further reading

General

• Evans, L. T. (1998). Feeding the Ten Billion - Plants and Population Growth. In Biology a population is the collection of inter-breeding organisms of a particular Species; in Sociology Cambridge University Press. Paperback, 247 pages. ISBN 0-521-64685-5.
• Kenrick, Paul & Crane, Peter R. (1997). The Origin and Early Diversification of Land Plants: A Cladistic Study. Washington, D. C. : Smithsonian Institution Press. ISBN 1-56098-730-8.
• Raven, Peter H. , Evert, Ray F. , & Eichhorn, Susan E. (2005). Biology of Plants (7th ed. ). New York: W. H. Freeman and Company. ISBN 0-7167-1007-2.
• Taylor, Thomas N. & Taylor, Edith L. (1993). The Biology and Evolution of Fossil Plants. Englewood Cliffs, NJ: Prentice Hall. ISBN 0-13-651589-4.
• Trewavas, A. (2003). Aspects of Plant Intelligence, Annals of Botany 92: 1-20.

Species estimates and counts

• Prance, G. T. (2001). Discovering the Plant World. Taxon 50: 345-359.
• International Union for Conservation of Nature and Natural Resources (IUCN) Species Survival Commission (2004). IUCN Red List of Threatened Species [1].

External links

• Tree of Life
• Answers to several questions from curious kids about plants
• Chaw, S. -M. et al. (1997). Molecular Phylogeny of Extant Gymnosperms and Seed Plant Evolution: Analysis of Nuclear 18s rRNA Sequences. Molec. Biol. Evol. 14 (1): 56–68.  
• Interactive Cronquist classification
• Plant Picture Gallery
• Plant Photo Gallery of Japan - Flavon's Wild herb and Alpine plants
• Plant Resources of Tropical Africa
• PROTAbase
• Index Nominum Algarum

Botanical and vegetation databases

• e-Floras (Flora of China, Flora of North America and others)
• PlantFiles - 150,000 plants
• Australia
• Chilean plants at Chilebosque
• Flora Europaea
• FloraWeb - Flora of Central Europe
• Flora of North America
• Native Plant Information Network
• United States Department of Agriculture
• List of Japanese Wild Plants Online
• Meet the Plants-National Tropical Botanical Garden
• African Plants Initiative database