Editing Botany (section)

== Plant anatomy and morphology ==
[[File:Oryza sativa - Köhler–s Medizinal-Pflanzen-232.jpg|thumb|alt=Colour image of a 19th-century illustration of the morphology of a rice plant|A nineteenth-century illustration showing the morphology of the roots, stems, leaves and flowers of the rice plant ''[[Oryza sativa]]'']]

[[Plant anatomy]] is the study of the structure of plant cells and tissues, whereas [[plant morphology]] is the study of their external form.{{sfn|Raven|Evert|Eichhorn|2005|p = 9}}
All plants are multicellular eukaryotes, their DNA stored in nuclei.{{sfn|Mauseth|2003|pp = 433–467}}{{sfn|National Center for Biotechnology Information|2004}} The characteristic features of [[plant cell]]s that distinguish them from those of animals and fungi include a primary [[cell wall]] composed of the polysaccharides [[cellulose]], [[hemicellulose]] and [[pectin]],{{Sfn|Mauseth|2003|pp = 62–81}} larger [[vacuole]]s than in animal cells and the presence of [[plastid]]s with unique photosynthetic and biosynthetic functions as in the chloroplasts. Other plastids contain storage products such as starch ([[amyloplasts]]) or lipids ([[elaioplast]]s). Uniquely, [[streptophyte]] cells and those of the green algal order [[Trentepohliales]]{{sfn|López-Bautista|Waters|Chapman|2003|pp = 1715–1718}} divide by construction of a [[phragmoplast]] as a template for building a [[cell plate]] late in [[cell division]].{{sfn|Lewis|McCourt|2004|pp=1535–1556}}

{{plain image with caption|File:Plant.svg|A diagram of a "typical" [[eudicot]], the most common type of plant (three-fifths of all plant species).{{sfn|Campbell|Reece|Urry|Cain|2008|pp=630, 738}} However, no plant actually looks exactly like this.|275px|left|bottom|triangle|#43d050}}

The bodies of [[vascular plant]]s including [[Lycopodiopsida|clubmosses]], [[fern]]s and [[spermatophyte|seed plants]] ([[gymnosperm]]s and [[angiosperms]]) generally have aerial and subterranean subsystems. The [[Shoot (botany)|shoot]]s consist of [[Plant stem|stems]] bearing green photosynthesising [[Leaf|leaves]] and reproductive structures. The underground vascularised [[root]]s bear [[root hairs]] at their tips and generally lack chlorophyll.{{sfn|Campbell|Reece|Urry|Cain|2008|p=739}} Non-vascular plants, the [[Marchantiophyta|liverworts]], [[hornworts]] and [[mosses]] do not produce ground-penetrating vascular roots and most of the plant participates in photosynthesis.{{sfn|Campbell|Reece|Urry|Cain|2008|pp = 607–608}} The [[sporophyte]] generation is nonphotosynthetic in liverworts but may be able to contribute part of its energy needs by photosynthesis in mosses and hornworts.{{sfn|Lepp|2012}}

The root system and the shoot system are interdependent – the usually nonphotosynthetic root system depends on the shoot system for food, and the usually photosynthetic shoot system depends on water and minerals from the root system.{{sfn|Campbell|Reece|Urry|Cain|2008|p = 739}} Cells in each system are capable of creating cells of the other and producing [[adventitious]] shoots or roots.{{sfn|Campbell|Reece|Urry|Cain|2008|pp = 812–814}} [[Stolons]] and [[tuber]]s are examples of shoots that can grow roots.{{sfn|Campbell|Reece|Urry|Cain|2008|p = 740}} Roots that spread out close to the surface, such as those of willows, can produce shoots and ultimately new plants.{{sfn|Mauseth|2003|pp = 185–208}} In the event that one of the systems is lost, the other can often regrow it. In fact it is possible to grow an entire plant from a single leaf, as is the case with plants in [[Streptocarpus sect. Saintpaulia|''Streptocarpus'' sect. ''Saintpaulia'']],{{sfn|Mithila|Hall|Victor|Saxena|2003|pp = 408–414}} or even a single [[Cell (biology)|cell]] – which can dedifferentiate into a [[Callus (cell biology)|callus]] (a mass of unspecialised cells) that can grow into a new plant.{{sfn|Campbell|Reece|Urry|Cain|2008|pp = 812–814}}
In vascular plants, the xylem and phloem are the conductive tissues that transport resources between shoots and roots. Roots are often adapted to store food such as sugars or [[starch]],{{sfn|Campbell|Reece|Urry|Cain|2008|p = 739}} as in [[sugar beet]]s and carrots.{{sfn|Mauseth|2003|pp = 185–208}}

Stems mainly provide support to the leaves and reproductive structures, but can store water in succulent plants such as [[Cactus|cacti]], food as in potato [[tubers]], or [[vegetative reproduction|reproduce vegetatively]] as in the [[stolons]] of [[strawberry#Cultivation|strawberry]] plants or in the process of [[layering]].{{sfn|Campbell|Reece|Urry|Cain|2008|p = 741}} Leaves gather sunlight and carry out [[photosynthesis]].{{sfn|Mauseth|2003|pp = 114–153}} Large, flat, flexible, green leaves are called foliage leaves.{{sfn|Mauseth|2003|pp = 154–184}} [[Gymnosperm]]s, such as [[conifer]]s, [[cycad]]s, ''[[Ginkgo]]'', and [[gnetophyta|gnetophytes]] are seed-producing plants with open seeds.{{sfn|Capon|2005|p = 11}} [[Angiosperms]] are [[Spermatophyte|seed-producing plants]] that produce flowers and have enclosed seeds.{{sfn|Mauseth|2003|pp = 720–750}} Woody plants, such as [[azalea]]s and [[oak]]s, undergo a secondary growth phase resulting in two additional types of tissues: wood (secondary [[xylem]]) and bark (secondary [[phloem]] and [[Cork cambium|cork]]). All gymnosperms and many angiosperms are woody plants.{{sfn|Mauseth|2003|pp = 209–243}} Some plants reproduce sexually, some asexually, and some via both means.{{sfn|Mauseth|2003|pp = 244–277}}

Although reference to major morphological categories such as root, stem, leaf, and trichome are useful, one has to keep in mind that these categories are linked through intermediate forms so that a continuum between the categories results.{{sfn|Sattler|Jeune|1992|pp = 249–269}} Furthermore, structures can be seen as processes, that is, process combinations.{{sfn|Sattler|1992|pp = 708–714}}

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