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Encyclopedia > Leaf
Look up foliage in Wiktionary, the free dictionary.
The leaves of a Beech tree
The leaves of a Beech tree
A leaf with laminar structure and pinnate venation
A leaf with laminar structure and pinnate venation
Vein skeleton of a leaf
Vein skeleton of a leaf

In botany, a leaf is an above-ground plant organ specialized for photosynthesis. For this purpose, a leaf is typically flat (laminar) and thin, to expose the cells containing chloroplast (chlorenchyma tissue, a type of parenchyma) to light over a broad area, and to allow light to penetrate fully into the tissues. Leaves are also the sites in most plants where transpiration and guttation take place. Leaves can store food and water, and are modified in some plants for other purposes. The comparable structures of ferns are correctly referred to as fronds. Furthermore, leaves are prominent in the human diet as leaf vegetables. Wikipedia does not have an article with this exact name. ... Wiktionary (a portmanteau of wiki and dictionary) is a multilingual, Web-based project to create a free content dictionary, available in over 151 languages. ... The word leaf may refer to: Leaf, an organ of a plant. ... Maple leaves Autumn leaf color is a phenomenon that affects the normally green leaves of many deciduous trees and shrubs by which they take on, during a few weeks in the autumn months, one or many colors that range from red to yellow. ... Image File history File links Leavessnipedale. ... Image File history File links Leavessnipedale. ... For other uses, see Beech (disambiguation). ... Image File history File links Download high-resolution version (1024x768, 158 KB) Leaf1. ... Image File history File links Download high-resolution version (1024x768, 158 KB) Leaf1. ... Image File history File links Metadata Size of this preview: 800 × 466 pixelsFull resolution (3371 × 1964 pixel, file size: 3. ... Image File history File links Metadata Size of this preview: 800 × 466 pixelsFull resolution (3371 × 1964 pixel, file size: 3. ... Pinguicula grandiflora commonly known as a Butterwort Example of a cross section of a stem [1] Botany is the scientific study of plant life. ... For other uses, see Plant (disambiguation). ... This article is about the biological unit. ... The leaf is the primary site of photosynthesis in plants. ... Chloroplasts are organelles found in plant cells and eukaryotic algae that conduct photosynthesis. ... Parenchyma is a term used to describe a bulk of a substance. ... For other uses, see Light (disambiguation). ... Transpiration is the evaporation of excess water from aerial parts and of plants, especially leaves but also stems, flowers and fruits. ... Guttation is the appearance of drops of water on the leaves of some vascular plants, such as grasses. ... Impact from a water drop causes an upward rebound jet surrounded by circular capillary waves. ... This article is about the group of pteridophyte plants. ... A fern with simple (lobed or pinnatifid) blades, the dissection of each blade not quite reaching to the rachis. ... This article is about modern humans. ... In nutrition, the diet is the sum of food consumed by a person or other organism. ... Fresh Swiss chard Fresh water spinach Creamed spinach Steamed kale Leaf vegetables, also called potherbs, greens, or leafy greens, are plant leaves eaten as a vegetable, sometimes accompanied by tender petioles and shoots. ...

Contents

Leaf anatomy

A structurally complete leaf of an angiosperm consists of a petiole (leaf stem), a lamina (leaf blade), and stipules (small processes located to either side of the base of the petiole). The petiole attaches to the stem at a point called the "leaf axil". Not every species produces leaves with all of the aforementioned structural components. In some species, paired stipules are not obvious or are absent altogether. A petiole may be absent, or the blade may not be laminar (flattened). The tremendous variety shown in leaf structure (anatomy) from species to species is presented in detail below under Leaf morphology. After a period of time (i.e. seasonally, during the autumn), deciduous trees shed their leaves. These leaves then decompose into the soil. Classes Magnoliopsida - Dicots Liliopsida - Monocots The flowering plants or angiosperms are the most widespread group of land plants. ... Leaf of Dog Rose (Rosa canina), showing the petiole and two leafy stipules In botany, the petiole is the small stalk attaching the leaf blade to the stem. ... The lanceolate-linear, paired stipules of Hibiscus kokio In botany, stipule refers to outgrowths borne on either side of the base of a leafstalk (or petiole). ...


A leaf is considered a plant organ and typically consists of the following tissues:

  1. An epidermis that covers the upper and lower surfaces
  2. An interior chlorenchyma called the mesophyll
  3. An arrangement of veins (the vascular tissue).

Image File history File links Leaf_anatomy. ...

Epidermis

The epidermis is the outer multi-layered group of cells covering the leaf. It forms the boundary separating the plant's inner cells from the external world. The epidermis serves several functions: protection against water loss, regulation of gas exchange, secretion of metabolic compounds, and (in some species) absorption of water. Most leaves show dorsoventral anatomy: the upper (adaxial) and lower (abaxial) surfaces have somewhat different construction and may serve different functions. The epidermis is the outer multi-layered group of cells covering the leaf and young tissues of a plant. ... Drawing of the structure of cork as it appeared under the microscope to Robert Hooke from Micrographia which is the origin of the word cell being used to describe the smallest unit of a living organism Cells in culture, stained for keratin (red) and DNA (green) The cell is the... Structure of the coenzyme adenosine triphosphate, a central intermediate in energy metabolism. ...


The epidermis is usually transparent (epidermal cells lack chloroplasts) and coated on the outer side with a waxy cuticle that prevents water loss. The cuticle is in some cases thinner on the lower epidermis than on the upper epidermis, and is thicker on leaves from dry climates as compared with those from wet climates. Transparent glass ball In optics, transparency is the property of allowing light to pass. ... Plant cuticles are a protective waxy covering produced only by the epidermal cells (Kolattukudy, 1996) of leaves, young shoots and all other aerial plant organs. ...


The epidermis tissue includes several differentiated cell types: epidermal cells, guard cells, subsidiary cells, and epidermal hairs (trichomes). The epidermal cells are the most numerous, largest, and least specialized. These are typically more elongated in the leaves of monocots than in those of dicots. Trichomes, from the Greek meaning growth of hair, are fine outgrowths or appendages on plants and protists. ... Orders Base Monocots: Acorus Alismatales Asparagales Dioscoreales Liliales Pandanales Family Petrosaviaceae Commelinids: Arecales Commelinales Poales Zingiberales Family Dasypogonaceae Monocotyledons or monocots are a group of flowering plants usually ranked as a class and once called the Monocotyledoneae. ... Orders see text Dicotyledons or dicots are flowering plants whose seed contains two embryonic leaves or cotyledons. ...


The epidermis is covered with pores called stomata, part of a stoma complex consisting of a pore surrounded on each side by chloroplast-containing guard cells, and two to four subsidiary cells that lack chloroplasts. The stoma complex regulates the exchange of gases and water vapor between the outside air and the interior of the leaf. Typically, the stomata are more numerous over the abaxial (lower) epidermis than the adaxial (upper) epidermis. Stoma of a leaf under a microscope. ...


Mesophyll

Most of the interior of the leaf between the upper and lower layers of epidermis is a parenchyma (ground tissue) or chlorenchyma tissue called the mesophyll (Greek for "middle leaf"). This assimilation tissue is the primary location of photosynthesis in the plant. The products of photosynthesis are called "assimilates". Parenchyma is a term used to describe a bulk of a substance. ... Chlorenchyma cells in plant anatomy are parenchyma cells that contain chloroplasts. ... This article or section is in need of attention from an expert on the subject. ...

Fallen leaves at autumn.
Fallen leaves at autumn.

In ferns and most flowering plants the mesophyll is divided into two layers: This article is about the temperate season. ...

  • An upper palisade layer of tightly packed, vertically elongated cells, one to two cells thick, directly beneath the adaxial epidermis. Its cells contain many more chloroplasts than the spongy layer. These long cylindrical cells are regularly arranged in one to five rows. Cylindrical cells, with the chloroplasts close to the walls of the cell, can take optimal advantage of light. The slight separation of the cells provides maximum absorption of carbon dioxide. This separation must be minimal to afford capillary action for water distribution. In order to adapt to their different environment (such as sun or shade), plants had to adapt this structure to obtain optimal result. Sun leaves have a multi-layered palisade layer, while shade leaves or older leaves closer to the soil, are single-layered.
  • Beneath the palisade layer is the spongy layer. The cells of the spongy layer are more rounded and not so tightly packed. There are large intercellular air spaces. These cells contain fewer chloroplasts than those of the palisade layer.

The pores or stomata of the epidermis open into substomatal chambers, connecting to air spaces between the spongy layer cells. Cross-section of a leaf Palisade cells are a type of leaf tissues and can be found within the mesophyll in leaves of dicotyledonous plants. ... Chloroplasts are organelles found in plant cells and eukaryotic algae which conduct photosynthesis. ... Absorption, in chemistry, is a physical or chemical phenomenon or a process in which atoms, molecules, or ions enter some bulk phase - gas, liquid or solid material. ... Capillary Flow Experiment to investigate capillary flows and phenomena onboard the International Space Station Capillary action, capillarity, capillary motion, or wicking is the ability of a substance to draw another substance into it. ...


These two different layers of the mesophyll are absent in many aquatic and marsh plants. Even an epidermis and a mesophyll may be lacking. Instead for their gaseous exchanges they use a homogeneous aerenchyma (thin-walled cells separated by large gas-filled spaces). Their stomata are situated at the upper surface. Aerenchyma is the spongy tissue occurring mainly in the stems of many aquatic or marsh plants. ...


Leaves are normally green in color, which comes from chlorophyll found in plastids in the chlorenchyma cells. Plants that lack chlorophyll cannot photosynthesize. For other uses, see Green (disambiguation). ... Chlorophyll is a green pigment found in most plants, algae, and cyanobacteria. ... Plant cells with visible chloroplasts. ... The leaf is the primary site of photosynthesis in plants. ...

Autumn Leaves
Autumn Leaves
Fallen autumn leaves
Fallen autumn leaves

Leaves in temperate, boreal, and seasonally dry zones may be seasonally deciduous (falling off or dying for the inclement season). This mechanism to shed leaves is called abscission. After the leaf is shed, a leaf scar develops on the twig. In cold autumns they sometimes change color, and turn yellow, bright orange or red as various accessory pigments (carotenoids and xanthophylls) are revealed when the tree responds to cold and reduced sunlight by curtailing chlorophyll production. Red anthocyanin pigments are now thought to be produced in the leaf as it dies. Image File history File links Download high resolution version (1600x1067, 349 KB) Please see the file description page for further information. ... Image File history File links Download high resolution version (1600x1067, 349 KB) Please see the file description page for further information. ... For the usage in virology, see temperate (virology). ... Boreal may refer to these: Northern from the eponymous Boreas, god of the North Wind in Greek mythology. ... For other uses, see Deciduous (disambiguation). ... Abscission (from ab- away from, and scission cutting or severing) is the shedding of a body part. ... Maple leaves Autumn leaf color is a phenomenon that affects the normally green leaves of many deciduous trees and shrubs by which they take on, during a few weeks in the autumn months, one or many colors that range from red to yellow. ... A yellow Tulip. ... The orange, the fruit from which the modern name of the orange colour comes. ... For other uses, see Red (disambiguation). ... The orange ring surrounding Grand Prismatic Spring is due to carotenoid molecules, produced by huge mats of algae and bacteria. ... This article or section does not cite its references or sources. ... Prism splitting light High Resolution Solar Spectrum Sunlight in the broad sense is the total spectrum of the electromagnetic radiation given off by the Sun. ...


Veins

The veins are the vascular tissue of the leaf and are located in the spongy layer of the mesophyll. They are typical examples of pattern formation through ramification. The pattern of the veins is called venation. Cross section of celery stalk, showing vascular bundles, which include both phloem and xylem. ... The science of pattern formation deals with the visible, (statistically) orderly outcomes of self-organisation and the common principles behind similar patterns. ... Naturally-occurring ramification helps gives these conifers a regular, cone-shaped outline. ... The arrangements of veins and veinlets is called venation. ...


The veins are made up of:

  • xylem, tubes that brings water and minerals from the roots into the leaf.
  • phloem, tubes that usually moves sap, with dissolved sucrose, produced by photosynthesis in the leaf, out of the leaf.

The xylem typically lies over the phloem. Both are embedded in a dense parenchyma tissue, called "pith", with usually some structural collenchyma tissue present. In vascular plants, xylem is one of the two types of transport tissue, phloem being the other one. ... In vascular plants, phloem is the living tissue that carries organic nutrients, particularly sucrose, a sugar, to all parts of the plant where needed. ...


Leaf morphology

Underside view of a leaf
Underside view of a leaf

External leaf characteristics (such as shape, margin, hairs, etc.) are important for identifying plant species, and botanists have developed a rich terminology for describing leaf characteristics. These structures are a part of what makes leaves determinant, they grow and achieve a specific pattern and shape, then stop. Other plant parts like stems or roots are non-determinant, and will usually continue to grow as long as they have the resources to do so. Leaf photo close-up, shot on a Nikon digital camera by Nicholas Moreau (user:zanimum) This image has been released into the public domain by the copyright holder, its copyright has expired, or it is ineligible for copyright. ... Leaf photo close-up, shot on a Nikon digital camera by Nicholas Moreau (user:zanimum) This image has been released into the public domain by the copyright holder, its copyright has expired, or it is ineligible for copyright. ... For other uses, see Species (disambiguation). ... Terminology is the study of terms and their use — of words and compound words that are used in specific contexts. ...


Classification of leaves can occur through many different designative schema, and the type of leaf is usually characteristic of a species, although some species produce more than one type of leaf. The longest type of leaf is a leaf from palm trees, measuring at nine feet long. The terminology associated with the description of leaf morphology is presented, in illustrated form, at Wikibooks.


Basic leaf types

Leaves of the White Spruce (Picea glauca) are needle-shaped and their arrangement is spiral
Leaves of the White Spruce (Picea glauca) are needle-shaped and their arrangement is spiral

Image File history File links Download high-resolution version (1024x1280, 205 KB) File links The following pages on the English Wikipedia link to this file (pages on other projects are not listed): Leaf Gymnosperm ... Image File history File links Download high-resolution version (1024x1280, 205 KB) File links The following pages on the English Wikipedia link to this file (pages on other projects are not listed): Leaf Gymnosperm ... This article is about the group of pteridophyte plants. ... A fern with simple (lobed or pinnatifid) blades, the dissection of each blade not quite reaching to the rachis. ... Orders & Families Cordaitales † Pinales   Pinaceae - Pine family   Araucariaceae - Araucaria family   Podocarpaceae - Yellow-wood family   Sciadopityaceae - Umbrella-pine family   Cupressaceae - Cypress family   Cephalotaxaceae - Plum-yew family   Taxaceae - Yew family Vojnovskyales † Voltziales † The conifers, division Pinophyta, are one of 13 or 14 division level taxa within the Kingdom Plantae. ... Classes Magnoliopsida - Dicots Liliopsida - Monocots The flowering plants or angiosperms are the most widespread group of land plants. ... Classes Lycopodiopsida - clubmosses Selaginellopsida - spikemosses Isoetopsida - quillworts The Division Lycopodiophyta (sometimes called Lycophyta) is a tracheophyte subdivision of the Kingdom Plantae. ... Microphylls are photosynthetic flaps of plant tissue with a solitary, unbranched vein. ... Hemerocallis flower, with three flower parts in each whorl Wheat, an economically important monocot The monocotyledons or Monocots are a group of flowering plants, (angiosperms) dominating great parts of the earth. ... Subfamilies There are 7 subfamilies: Subfamily Arundinoideae Subfamily Bambusoideae Subfamily Centothecoideae Subfamily Chloridoideae Subfamily Panicoideae Subfamily Pooideae Subfamily Stipoideae The true grasses are monocotyledonous plants (Class Liliopsida) in the Family Poaceae, also known as Gramineae. ... Species See text The genus Nepenthes (Tropical Pitcher Plants or Monkey Cups) in the monotypic family Nepenthaceae contains roughly 80-100 species, (depending on author), several natural and many cultivated hybrids. ...

Arrangement on the stem

Different terms are usually used to describe leaf placement (phyllotaxis): In botany, phyllotaxis is the arrangement of the leaves on the shoot of a plant. ...

The leaves on this plant are arranged in pairs opposite one another, with successive pairs at right angles to each other ("decussate") along the red stem. Note developing buds in the axils of these leaves.
The leaves on this plant are arranged in pairs opposite one another, with successive pairs at right angles to each other ("decussate") along the red stem. Note developing buds in the axils of these leaves.
  • Alternate — leaf attachments are singular at nodes, and leaves alternate direction, to a greater or lesser degree, along the stem.
  • Opposite — leaf attachments are paired at each node; decussate if, as typical, each successive pair is rotated 90° progressing along the stem; or distichous if not rotated, but two-ranked (in the same geometric flat-plane).
  • Whorled — three or more leaves attach at each point or node on the stem. As with opposite leaves, successive whorls may or may not be decussate, rotated by half the angle between the leaves in the whorl (i.e., successive whorls of three rotated 60°, whorls of four rotated 45°, etc). Opposite leaves may appear whorled near the tip of the stem.
  • Rosulate — leaves form a rosette

As a stem grows, leaves tend to appear arranged around the stem in a way that optimizes yield of light. In essence, leaves form a helix pattern centred around the stem, either clockwise or counterclockwise, with (depending upon the species) the same angle of divergence. There is a regularity in these angles and they follow the numbers in a Fibonacci sequence: 1/2, 2/3, 3/5, 5/8, 8/13, 13/21, 21/34, 34/55, 55/89. This series tends to a limit of 360° x 34/89 = 137.52 or 137° 30', an angle known mathematically as the golden angle. In the series, the numerator indicates the number of complete turns or "gyres" until a leaf arrives at the initial position. The denominator indicates the number of leaves in the arrangement. This can be demonstrated by the following: Download high resolution version (950x683, 185 KB)Photo of plant (Alternanthera sp. ... Download high resolution version (950x683, 185 KB)Photo of plant (Alternanthera sp. ... A rosette of leaves at the base of a dandelion In botany, a rosette is a circular arrangement of the leaves, with all the leaves at a single height. ... A helix (pl: helices), from the Greek word έλικας/έλιξ, is a twisted shape like a spring, screw or a spiral (correctly termed helical) staircase. ... A clockwise motion is one that proceeds like the clocks hands: from the top to the right, then down and then to the left, and back to the top. ... In mathematics, the Fibonacci numbers form a sequence defined recursively by: In words: you start with 0 and 1, and then produce the next Fibonacci number by adding the two previous Fibonacci numbers. ... The golden angle is the angle subtended by the smaller (red) arc when two arcs that make up a circle are in the golden ratio In geometry, the golden angle is the smaller of the two angles created by sectioning the circumference of a circle according to the golden section... In algebra, a vulgar fraction consists of one integer divided by a non-zero integer. ...

  • alternate leaves have an angle of 180° (or 1/2)
  • 120° (or 1/3) : three leaves in one circle
  • 144° (or 2/5) : five leaves in two gyres
  • 135° (or 3/8) : eight leaves in three gyres.

The fact that an arrangement of anything in nature can be described by a mathematical formula is not in itself mysterious. Mathematics are the science of discovering numerical relationships and applying formulae to these relationships. The formulae themselves can provide clues to the underlying physiological processes that, in this case, determine where the next leaf bud will form in the elongating stem. For other meanings of mathematics or uses of math and maths, see Mathematics (disambiguation) and Math (disambiguation). ... A formula is a concise way of expressing information symbolically (as in a mathematical or chemical formula) or a general relationship between quantities. ...


Divisions of the lamina (blade)

Two basic forms of leaves can be described considering the way the blade is divided. A simple leaf has an undivided blade. However, the leaf shape may be formed of lobes, but the gaps between lobes do not reach to the main vein. A compound leaf has a fully subdivided blade, each leaflet of the blade separated along a main or secondary vein. Because each leaflet can appear to be a simple leaf, it is important to recognize where the petiole occurs to identify a compound leaf. Compound leaves are a characteristic of some families of higher plants, such as the Fabaceae. The middle vein of a compound leaf or a frond, when it is present, is called a rachis. A leaflet in botany is a part of a compound leaf. ... Subfamilies Faboideae Caesalpinioideae Mimosoideae References GRIN-CA 2002-09-01 The name Fabaceae belongs to either of two families, depending on viewpoint. ... A fern with simple (lobed or pinnatifid) blades, the dissection of each blade not quite reaching to the rachis. ... Rachis type barley Rachis is also the alternate spelling of Ratchis, king of the Lombards, 744-749. ...

  • Palmately compound leaves have the leaflets radiating from the end of the petiole, like fingers off the palm of a hand, e.g. Cannabis (hemp) and Aesculus (buckeyes).
  • Pinnately compound leaves have the leaflets arranged along the main or mid-vein.
    • odd pinnate: with a terminal leaflet, e.g. Fraxinus (ash).
    • even pinnate: lacking a terminal leaflet, e.g. Swietenia (mahogany).
  • Bipinnately compound leaves are twice divided: the leaflets are arranged along a secondary vein that is one of several branching off the rachis. Each leaflet is called a "pinnule". The pinnules on one secondary vein are called "pinna"; e.g. Albizia (silk tree).
  • trifoliate: a pinnate leaf with just three leaflets, e.g. Trifolium (clover), Laburnum (laburnum).
  • pinnatifid: pinnately dissected to the midrib, but with the leaflets not entirely separate, e.g. Polypodium, some Sorbus (whitebeams).

This article is about the plant genus Cannabis. ... Species Aesculus arguta: Texas Buckeye Aesculus californica: California Buckeye Aesculus chinensis: Chinese Horse-chestnut Aesculus flava (): Yellow Buckeye Aesculus glabra: Ohio Buckeye Aesculus hippocastanum: Common Horse-chestnut Aesculus indica: Indian Horse-chestnut Aesculus neglecta: Dwarf Buckeye Aesculus parviflora: Bottlebrush Buckeye Aesculus pavia: Red Buckeye Aesculus sylvatica: Painted Buckeye Aesculus turbinata... Species See text European Ash in flower Narrow-leafed Ash (Fraxinus angustifolia) shoot with leaves Closeup of European Ash seeds 19th century illustration of Manna Ash (Fraxinus ornus) An ash can be any of four different tree genera from four very distinct families (see end of page for disambiguation), but... This article is about the timber. ... Species See List of Albizia species Albizia (syn. ... For other uses, see Clover (disambiguation). ... Species Laburnum anagyroides Laburnum alpinum Laburnum is a genus of two species of small trees in the subfamily Faboideae of the pea family Fabaceae, Laburnum anagyroides (Common Laburnum) and (Alpine Laburnum). ... Species See text Polypodium is a large genus of true ferns, widely distributed throughout the world, but specially developed in the tropics. ... Subgenera Sorbus Aria Micromeles Cormus Torminaria Chamaemespilus The genus Sorbus is a genus of about 100-200 species of trees and shrubs in the subfamily Maloideae of the Rose family Rosaceae. ...

Characteristics of the petiole

The overgrown petioles of Rhubarb (Rheum rhabarbarum) are edible.
The overgrown petioles of Rhubarb (Rheum rhabarbarum) are edible.

Petiolated leaves have a petiole. Sessile leaves do not: the blade attaches directly to the stem. In clasping or decurrent leaves, the blade partially or wholly surrounds the stem, often giving the impression that the shoot grows through the leaf. When this is actually the case, the leaves are called "perfoliate", such as in Claytonia perfoliata. In peltate leaves, the petiole attaches to the blade inside from the blade margin. Image File history File links Rabarber_stelen. ... Image File history File links Rabarber_stelen. ... For other uses see Rhubarb (disambiguation) Species About 60, including: R. nobile R. palmatum Rhubarb is a perennial plant that grows from thick short rhizomes, comprising the genus Rheum. ... Leaf of Dog Rose (Rosa canina), showing the petiole and two leafy stipules In botany, the petiole is the small stalk attaching the leaf blade to the stem. ... Binomial name Claytonia perfoliata Donn ex Willd. ...


In some Acacia species, such as the Koa Tree (Acacia koa), the petioles are expanded or broadened and function like leaf blades; these are called phyllodes. There may or may not be normal pinnate leaves at the tip of the phyllode. For other uses, see Acacia (disambiguation). ... A young Koa tree showing compound leaves and phyllodes The Koa (Acacia koa; Family Fabaceae) is a large tree endemic to the Australian and Pacific islands acacias) in that the leaves produced early in the growth of the plant are compound leaves typical of the pea family. ... Phyllodes are modified petioles or leaf stems. ...


A stipule, present on the leaves of many dicotyledons, is an appendage on each side at the base of the petiole resembling a small leaf. Stipules may be lasting and not be shed (a stipulate leaf, such as in roses and beans), or be shed as the leaf expands, leaving a stipule scar on the twig (an exstipulate leaf). The lanceolate-linear, paired stipules of Hibiscus kokio In botany, stipule refers to outgrowths borne on either side of the base of a leafstalk (or petiole). ... Orders See text. ... For other uses, see Rose (disambiguation). ... Green beans Bean is a common name for large plant seeds of several genera of Fabaceae (formerly Leguminosae) used for food or feed. ...

  • The situation, arrangement, and structure of the stipules is called the "stipulation".
    • free
    • adnate : fused to the petiole base
    • ochreate : provided with ochrea, or sheath-formed stipules, e.g. rhubarb,
    • encircling the petiole base
    • interpetiolar : between the petioles of two opposite leaves.
    • intrapetiolar : between the petiole and the subtending stem

In botany, stipule (Latin stipula: straw, stalk[1]) is a term coined by Linnaeus[1] which refers to outgrowths borne on either side of the base of a leafstalk (the petiole). ... For other uses see Rhubarb (disambiguation) Species About 60, including: R. nobile R. palmatum Rhubarb is a perennial plant that grows from thick short rhizomes, comprising the genus Rheum. ...

Venation (arrangement of the veins)

Palmate-veined leaf
Palmate-veined leaf
Vein skeleton of a Hydrangea leaf

There are two subtypes of venation, namely, craspedodromous, where the major veins stretch up to the margin of the leaf, and camptodromous, when major veins extend close to the margin, but bend before they intersect with the margin. Palmate-veined leaf File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ... Palmate-veined leaf File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ... Image File history File linksMetadata Download high-resolution version (800x700, 144 KB)HELLO File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ... Image File history File linksMetadata Download high-resolution version (800x700, 144 KB)HELLO File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ... Species See text Hydrangea (common names also Hydrangea, in English pronounced IPA , and Hortensia) is a genus of about 70-75 species of flowering plants native to southern and eastern Asia (from Japan to China, the Himalaya and Indonesia) and North and South America. ...

  • Feather-veined, reticulate — the veins arise pinnately from a single mid-vein and subdivide into veinlets. These, in turn, form a complicated network. This type of venation is typical for (but by no means limited to) dicotyledons.
    • Pinnate-netted, penniribbed, penninerved, penniveined; the leaf has usually one main vein (called the mid-vein), with veinlets, smaller veins branching off laterally, usually somewhat parallel to each other; eg Malus (apples).
    • Three main veins branch at zhe base of the lamina and run essentially parallel subsequently, as in Ceanothus. A similar pattern (with 3-7 veins) is especially conspicuous in Melastomataceae.
    • Palmate-netted, palmate-veined, fan-veined; several main veins diverge from near the leaf base where the petiole attaches, and radiate toward the edge of the leaf; e.g. most Acer (maples).
  • Parallel-veined, parallel-ribbed, parallel-nerved, penniparallel — veins run parallel for the length of the leaf, from the base to the apex. Commissural veins (small veins) connect the major parallel veins. Typical for most monocotyledons, such as grasses.
  • Dichotomous — There are no dominant bundles, with the veins forking regularly by pairs; found in Ginkgo and some pteridophytes.

Note that although it is the more complex pattern, branching veins appear to be plesiomorphic and in some form were present in ancient seed plants as long as 250 million years ago. A pseudo-reticulate venation that is actually a highly modified penniparallel one is an autapomorphy of some Melanthiaceae which are monocots, e.g. Paris quadrifolia (True-lover's Knot). Orders See text. ... Species Malus angustifolia - Southern Crab Malus baccata - Siberian Crabapple Malus bracteata Malus brevipes Malus coronaria - Sweet Crabapple Malus domestica - Apple Malus florentina Malus floribunda - Japanese Crabapple Malus formosana Malus fusca - Oregon Crab, Pacific Crab Malus glabrata Malus glaucescens Malus halliana Malus honanensis Malus hupehensis - Chinese Crabapple Malus ioensis - Prairie Crab... Species See text Ceanothus L., is a genus of about 50-60 species of shrubs or small trees in the buckthorn family Rhamnaceae. ... Genera See text. ... In vector calculus, the divergence is an operator that measures a vector fields tendency to originate from or converge upon a given point. ... For other uses, see Maple (disambiguation). ... Parallel is a term in geometry and in everyday life that refers to a property in Euclidean space of two or more lines or planes, or a combination of these. ... Hemerocallis flower, with three flower parts in each whorl Wheat, an economically important monocot The monocotyledons or Monocots are a group of flowering plants, (angiosperms) dominating great parts of the earth. ... Subfamilies There are 7 subfamilies: Subfamily Arundinoideae Subfamily Bambusoideae Subfamily Centothecoideae Subfamily Chloridoideae Subfamily Panicoideae Subfamily Pooideae Subfamily Stipoideae The true grasses are monocotyledonous plants (Class Liliopsida) in the Family Poaceae, also known as Gramineae. ... Species G. biloba L. The Ginkgo (Ginkgo biloba; 銀杏 in Chinese), frequently misspelled as Gingko, and also known as the Maidenhair Tree, is a unique tree with no close living relatives. ... This article is about the group of pteridophyte plants. ... This cladogram shows the relationship among various insect groups. ... The spermatophytes comprise those plants that produce seeds. ... An autapomorphy in cladistics is a derived trait that is unique to a given taxon. ... Genera See text The family Melanthiaceae (formerly Trilliaceae) consists of a number of genera petaloid, lilioid monocot flowering plants. ... Binomial name Paris quadrifolia Linnaeus, Paris quadrifolia is a species of the genus Paris in the family Melanthiaceae although authorities formerly regarded it as part of the Liliaceae family. ...


Leaf morphology changes within a single plant

  • Homoblasty - Characteristic in which a plant has small changes in leaf size, shape, and growth habit between juvenile and adult stages.
  • Heteroblasty - Charactistic in which a plant has marked changes in leaf size, shape, and growth habit between juvenile and adult stages.



Leaf terminology

Chart illustrating some leaf morphology terms
Chart illustrating some leaf morphology terms

Image File history File links Download high resolution version (2163x1977, 603 KB) Summary Chart of leaf morphology characteristics. ... Image File history File links Download high resolution version (2163x1977, 603 KB) Summary Chart of leaf morphology characteristics. ...

Shape

Main article: Leaf shape

In botany, the following terms are used to describe the shape of plant leaves: cordate leaf Acicular: slender and pointed Alternate (alternifolia): Arranged alternately Bipinnate (bipinnata): Each leaflet also pinnate Cordate (cordata): Heart-shaped, stem attaches to cleft Cuneate: Triangular, stem attaches to point Deltoid: Triangular, stem attaches to side...

Margins (edge)

The leaf margin is characteristic for a genus and aids in determining the species.

  • entire: even; with a smooth margin; without toothing
  • ciliate: fringed with hairs
  • crenate: wavy-toothed; dentate with rounded teeth, such as Fagus (beech)
  • dentate: toothed, such as Castanea (chestnut)
    • coarse-toothed: with large teeth
    • glandular toothed: with teeth that bear glands.
  • denticulate: finely toothed
  • doubly toothed: each tooth bearing smaller teeth, such as Ulmus (elm)
  • lobate: indented, with the indentations not reaching to the center, such as many Quercus (oaks)
    • palmately lobed: indented with the indentations reaching to the center, such as Humulus (hop).
  • serrate: saw-toothed with asymmetrical teeth pointing forward, such as Urtica (nettle)
  • serrulate: finely serrate
  • sinuate: with deep, wave-like indentations; coarsely crenate, such as many Rumex (docks)
  • spiny: with stiff, sharp points, such as some Ilex (hollies) and Cirsium (thistles).

For other uses, see Beech (disambiguation). ... Species Castanea alnifolia - Bush Chinkapin* Castanea crenata - Japanese Chestnut Castanea dentata - American Chestnut Castanea henryi - Henrys Chestnut Castanea mollissima - Chinese Chestnut Castanea ozarkensis - Ozark Chinkapin Castanea pumila - Allegheny Chinkapin Castanea sativa - Sweet Chestnut Castanea seguinii - Seguins Chestnut * treated as a synonym of by many authors Chestnut is a... Species See Elm species, varieties, cultivars and hybrids Elms are deciduous and semi-deciduous trees making up the genus Ulmus, family Ulmaceae, found throughout the Northern Hemisphere from Siberia to Indonesia, Mexico to Japan. ... Species See List of Quercus species The term oak can be used as part of the common name of any of several hundred species of trees and shrubs in the genus Quercus (from Latin oak tree), which are listed in the List of Quercus species, and some related genera, notably... Species Humulus lupulus L. Humulus japonicus Siebold & Zucc. ... Nettles redirects here. ... Species About 200, see text. ... This article is about the plant. ... Milk thistle flowerhead Thistledown a method of seed dispersal by wind. ...

Tip of the leaf

Leaves showing various morphologies. Clockwise from upper left: tripartite lobation, elliptic with serrulate margin, peltate with palmate venation, acuminate odd-pinnate (center), pinnatisect, lobed, elliptic with entire margin
Leaves showing various morphologies. Clockwise from upper left: tripartite lobation, elliptic with serrulate margin, peltate with palmate venation, acuminate odd-pinnate (center), pinnatisect, lobed, elliptic with entire margin
  • acuminate: long-pointed, prolonged into a narrow, tapering point in a concave manner.
  • acute: ending in a sharp, but not prolonged point
  • cuspidate: with a sharp, elongated, rigid tip; tipped with a cusp.
  • emarginate: indented, with a shallow notch at the tip.
  • mucronate: abruptly tipped with a small short point, as a continuation of the midrib; tipped with a mucro.
  • mucronulate: mucronate, but with a smaller spine.
  • obcordate: inversely heart-shaped, deeply notched at the top.
  • obtuse: rounded or blunt
  • truncate: ending abruptly with a flat end, that looks cut off.

Image File history File links Download high resolution version (847x1159, 108 KB) Summary leaves scanned by me, User debivort 1998. ... Image File history File links Download high resolution version (847x1159, 108 KB) Summary leaves scanned by me, User debivort 1998. ...

Base of the leaf

  • acuminate: coming to a sharp, narrow, prolonged point.
  • acute: coming to a sharp, but not prolonged point.
  • auriculate: ear-shaped
  • cordate: heart-shaped with the notch towards the stalk.
  • cuneate: wedge-shaped.
  • hastate: shaped like an halberd and with the basal lobes pointing outward.
  • oblique: slanting.
  • reniform: kidney-shaped but rounder and broader than long.
  • rounded: curving shape.
  • sagittate: shaped like an arrowhead and with the acute basal lobes pointing downward.
  • truncate: ending abruptly with a flat end, that looks cut off.

Surface of the leaf

Scale-shaped leaves of a Norfolk Island Pine, Araucaria heterophylla.
Scale-shaped leaves of a Norfolk Island Pine, Araucaria heterophylla.

The surface of a leaf can be described by several botanical terms: Image File history File linksMetadata Download high-resolution version (576x800, 412 KB) Close up of Norfolk Pine needles. ... Image File history File linksMetadata Download high-resolution version (576x800, 412 KB) Close up of Norfolk Pine needles. ... Binomial name Araucaria heterophylla (Salisb. ...

  • farinose: bearing farina; mealy, covered with a waxy, whitish powder.
  • glabrous: smooth, not hairy.
  • glaucous: with a whitish bloom; covered with a very fine, bluish-white powder.
  • glutinous: sticky, viscid.
  • papillate, papillose: bearing papillae (minute, nipple-shaped protuberances).
  • pubescent: covered with erect hairs (especially soft and short ones)
  • punctate: marked with dots; dotted with depressions or with translucent glands or colored dots.
  • rugose: deeply wrinkled; with veins clearly visible.
  • scurfy: covered with tiny, broad scalelike particles.
  • tuberculate: covered with tubercles; covered with warty prominences.
  • verrucose: warted, with warty outgrowths.
  • viscid, viscous: covered with thick, sticky secretions.

The leaf surface is also host to a large variety of microorganisms; in this context it is referred to as the phyllosphere. A microorganism or microbe is an organism that is so small that it is microscopic (invisible to the naked eye). ... The phyllosphere is a term used in microbiology to refer to leaf surfaces or total above-ground surfaces of a plant as a habitat for microorganisms. ...


Hairiness (trichomes)

Common Mullein (Verbascum thapsus) leaves are covered in dense, stellate trichomes.
Scanning electron microscope image of trichomes on the lower surface of a Coleus blumei [coleus] leaf.
Scanning electron microscope image of trichomes on the lower surface of a Coleus blumei [coleus] leaf.

"Hairs" on plants are properly called trichomes. Leaves can show several degrees of hairiness. The meaning of several of the following terms can overlap. Image File history File linksMetadata Download high-resolution version (1224x1632, 1060 KB) http://www. ... Image File history File linksMetadata Download high-resolution version (1224x1632, 1060 KB) http://www. ... Binomial name Verbascum thapsus L. Verbascum thapsus (Common or Great Mullein) is a species of mullein, native to Europe, northern Africa and Asia, and introduced in the Americas and Australia. ... Image File history File links Size of this preview: 585 × 599 pixelsFull resolution‎ (1,024 × 1,049 pixels, file size: 315 KB, MIME type: image/jpeg) File historyClick on a date/time to view the file as it appeared at that time. ... Image File history File links Size of this preview: 585 × 599 pixelsFull resolution‎ (1,024 × 1,049 pixels, file size: 315 KB, MIME type: image/jpeg) File historyClick on a date/time to view the file as it appeared at that time. ... Trichomes, from the Greek meaning growth of hair, are fine outgrowths or appendages on plants and protists. ...

  • glabrous: no hairs of any kind present.
  • arachnoid, arachnose: with many fine, entangled hairs giving a cobwebby appearance.
  • barbellate: with finely barbed hairs (barbellae).
  • bearded: with long, stiff hairs.
  • bristly: with stiff hair-like prickles.
  • canescent: hoary with dense grayish-white pubescence.
  • ciliate: marginally fringed with short hairs (cilia).
  • ciliolate: minutely ciliate.
  • floccose: with flocks of soft, woolly hairs, which tend to rub off.
  • glandular: with a gland at the tip of the hair.
  • hirsute: with rather rough or stiff hairs.
  • hispid: with rigid, bristly hairs.
  • hispidulous: minutely hispid.
  • hoary: with a fine, close grayish-white pubescence.
  • lanate, lanose: with woolly hairs.
  • pilose: with soft, clearly separated hairs.
  • puberulent, puberulous: with fine, minute hairs.
  • pubescent: with soft, short and erect hairs.
  • scabrous, scabrid: rough to the touch
  • sericeous: silky appearance through fine, straight and appressed (lying close and flat) hairs.
  • silky: with adpressed, soft and straight pubescence.
  • stellate, stelliform: with star-shaped hairs.
  • strigose: with appressed, sharp, straight and stiff hairs.
  • tomentose: densely pubescent with matted, soft white woolly hairs.
    • cano-tomentose: between canescent and tomentose
    • felted-tomentose: woolly and matted with curly hairs.
  • villous: with long and soft hairs, usually curved.
  • woolly: with long, soft and tortuous or matted hairs.

Adaptations

Poinsettia bracts are leaves which have evolved red pigmentation in order to attract insects and birds to the central flowers, an adaptive function normally served by petals (which are themselves highly modified leaves).
Poinsettia bracts are leaves which have evolved red pigmentation in order to attract insects and birds to the central flowers, an adaptive function normally served by petals (which are themselves highly modified leaves).

In the course of evolution, leaves adapted to different environments in the following ways: Image File history File links No higher resolution available. ... Image File history File linksMetadata Download high resolution version (2592x1944, 1232 KB) Summary Photo of Poinsettia, taken by Vineeth. ... Image File history File linksMetadata Download high resolution version (2592x1944, 1232 KB) Summary Photo of Poinsettia, taken by Vineeth. ... Binomial name Willd. ... Toothed bracts on Rhinanthus minor In botany, a bract is a modified or specialized leaf, from the axil of which a flower or flower stalk arises; or a bract may be any leaf associated with an inflorescence. ... It has been suggested that Corolla be merged into this article or section. ...

  • A certain surface structure avoids moistening by rain and contaminations (Lotus effect).
  • Sliced leaves reduce wind resistance.
  • Hairs on the leaf surface trap humidity in dry climates and creates a large boundary layer and reduces water loss.
  • Waxy leaf surfaces reduce water loss.
  • Shiny leaves deflect the sun's rays.
  • Reductions of leaf sizes accompanied by a transfer of the photosynthetic functions to the stems reduces water loss.
  • In more or less opaque or buried in the soil leaves translucent windows filter the light before the photosynthetis takes place at the inner leaf surfaces (e.g. Fenestraria).
  • Thicker leaves store water (leaf succulents).
  • Aromatic oils, poisons or pheromones produced by leaf borne glands deter herbivores (e.g. eucalypts).
  • Inclusions of crystalline minerals deters herbivores.
  • A transformation into petals attracts pollinators.
  • A transformation into spines protects the plants (e.g. cactus).
  • A transformation into insect traps helps feeding the plants (carnivorous plants).
  • A transformation into bulbs helps storing food and water (e.g. onion).
  • A transformation into tendrils allow the plant to climb (e.g. pea).
  • A transformation into bracts and pseudanthia (false flowers) replaces normal flower structures if the true flowers are extremely reduced (e.g. Spurges).

Water on the surface of a lotus leaf The Lotus effect in material science is the observed self-cleaning property found with lotus plants. ... candle wax This page is about the substance. ... Sol redirects here. ... Species Fenestraria rhopalophylla Fenestraria is a monotypic genus of succulent plants in the family Aizoaceae. ... Succulent plants, or succulents, are plants that store water in their enlarged fleshy leaves, stems, or roots. ... Fragrance oils, also known as aroma oils, aromatic oils, and flavor oils, are blended synthetic aroma compounds or natural essential oils that are diluted with a carrier like propylene glycol, vegetable oil, or mineral oil. ... This article is about the dangerous substance. ... Fanning honeybee exposes Nasonov gland (white-at tip of abdomen) releasing pheromone to entice swarm into an empty hive A pheromone is any chemical produced by a living organism that transmits a message to other members of the same species. ... Species About 600, see text Eucalyptus is a diverse genus of trees (rarely shrubs), the members of which dominate the tree flora of Australia. ... It has been suggested that Corolla be merged into this article or section. ... Raised thorns on the stem of the wait-a-bit climber Prickles on rose stems Thorns of the Ocotillo A spine is a rigid, pointed surface protuberance or needle-like structure on an animal, shell, or plant, presumably serving as a defense against attack by predators. ... Subfamilies Cactoideae Maihuenioideae Opuntioideae Pereskioideae See also taxonomy of the Cactaceae A cactus (plural cacti, cactuses or cactus) is any member of the succulent plant family Cactaceae, native to the Americas. ... Nepenthes mirabilis in flower, growing on a road cut in Palau Carnivorous plants (sometimes called insectivorous plants) are plants that derive some or most of their nutrients (but not energy) from trapping and consuming animals or protozoans, most focusing on insects and other arthropods. ... Shallot bulbs A bulb is an underground vertical shoot that has modified leaves (or thickened leaf bases) that is used as food storage organs by a dormant plant. ... For other uses, see Onion (disambiguation). ... In botany, a tendril is a specialized stem, leaf or petiole with a threadlike shape that is used by climbing plants for support and attachment, generally by twining around whatever it touches. ... Binomial name L. Percentages are relative to US recommendations for adults. ... Toothed bracts on Rhinanthus minor In botany, a bract is a modified or specialized leaf, from the axil of which a flower or flower stalk arises; or a bract may be any leaf associated with an inflorescence. ... A pseudanthium (Greek: false flower) is a special type of inflorescence, in which several flowers are grouped together to form a flower-like structure. ... Species See full list. ...

Interactions with other organisms

Leaf insects mimic leaves.
Leaf insects mimic leaves.

Although not as nutritious as other organs such as fruit, leaves provide a food source for many organisms. Animals which eat leaves are known as folivores. The leaf is one of the most vital parts of the plant, and plants have evolved protection against folivores such as tannins, chemicals which hinder the digestion of proteins and have an unpleasant taste. Some animals have cryptic adaptations to avoid their own predators, for example some caterpillars will create a small home in the leaf by folding it over themselves, while other herbivores and their prey mimic the appearance of the leaf. Some insects, such as the katydid, take this even further, moving from side to side much like a leaf does in the wind. Image File history File links LeafInsect. ... Image File history File links LeafInsect. ... Genera Chitoniscus Microphyllium Nanophyllium Phyllium Eophyllium (extinct) The family Phylliidae (often misspelled Phyllidae) contains the extant true leaf insects or walkingleaves, which include some of the most remarkable leaf mimics in the entire animal kingdom. ... In Zoology, a folivore is an animal that specializes in eating leaves. ... A bottle of tannic acid. ... Crypsis is a phenomena where an organisms appearance allows it to blend well into its environment. ... For other uses, see Mimic (disambiguation). ... Subfamilies See text. ...


Bibliography

  • Leaves: The formation, charactistics and uses of hundred of leaves in all parts of the world by Ghillean Tolmie Prance. 324 photographic plates in black and white, and colour by Kjell B Sandved 256 pages[1]

Sir Ghillean Tolmie Prance (b. ...

Footnotes

  1. ^ Published by Thames and Hudson (London) with an ISBN 0 500 54104 3

This article is about the capital of England and the United Kingdom. ...

See also

Abscission (from ab- away from, and scission cutting or severing) is the shedding of a body part. ... Cladophylls also called cladodes are photosynthetic branches or portions of a stem that resemble and function as a leaf, as in the asparagus. ... Guttation is the appearance of drops of water on the leaves of some vascular plants, such as grasses. ... The Leaf Area Index or LAI is the ratio of total upper leaf surface of a crop divided by the surface area of the land on which the crop grows. ... Phylloclades are flattened, photosynthetic branches or stems that resemble or perform the function of a leaf, as in certain cacti. ... This Australian tree fern is producing a new frond by the process of circinate vernation Vernation (from vernal, since that is when leaves spring forth in Temperate regions) is the formation of new leaves or fronds. ... Evolutionary developmental biology (evo-devo) refers to the study of developmental programs and patterns from an evolutionary perspective. ... Image File history File links Question_book-3. ...

External links

Wikimedia Commons has media related to:
Leaves


Image File history File links Commons-logo. ...

Pinguicula grandiflora commonly known as a Butterwort Example of a cross section of a stem [1] Botany is the scientific study of plant life. ... Ethnobotany is the study of the relationship between plants and people: Fromethno - study of people and botany - study of plants. ... Paleobotany (from the Greek words paleon = old and botanikos = of herbs) is the branch of paleontology dealing with the recovery and identification of plant remains from geological contexts, and their use in the reconstruction of past environments and the history of life. ... Plant anatomy or phytotomy is the general term for the study of the structure of plants. ... For the journal, see Ecology (journal). ... Evolutionary developmental biology (evo-devo) refers to the study of developmental programs and patterns from an evolutionary perspective. ... Plant anatomy or phytotomy is the general term for the study of the structure of plants. ... A germination rate experiment Plant physiology is a subdiscipline of botany concerned with the function, or physiology, of plants. ... Download high resolution version (454x765, 178 KB)Coconut Palm on Martinique. ... For other uses, see Plant (disambiguation). ... Plant evolution is an aspect of the study of biological evolution, involving predominantly the evolution of plants suited to live on land, the greening of the various land masses by the filling of their niches with land plants, and the diversification of the groups of land plants. ... Osborne (talk) 20:17, 5 December 2007 (UTC):For the programming language, see algae (programming language) Laurencia, a marine red alga from Hawaii. ... The bryophytes are those embryophytes (land plants) that are non-vascular: they have tissues and enclosed reproductive systems, but they lack vascular tissue that circulates liquids. ... Classes Marattiopsida Osmundopsida Gleicheniopsida Pteridopsida A fern, or pteridophyte, is any one of a group of some twenty thousand species of plants classified in the Division Pteridophyta, formerly known as Filicophyta. ... Divisions Pinophyta (or Coniferophyta) - Conifers Ginkgophyta - Ginkgo Cycadophyta - Cycads Gnetophyta - Gnetum, Ephedra, Welwitschia The gymnosperms (Gymnospermae) are a group of spermatophyte seed-bearing plants with ovules on the edge or blade of an open sporophyll, the sporophylls usually arranged in cone-like structures. ... Classes Magnoliopsida - Dicots Liliopsida - Monocots The flowering plants or angiosperms are the most widespread group of land plants. ... For other uses, see Flower (disambiguation). ... For other uses, see Fruit (disambiguation). ... Tunica-Corpus model of the apical meristem. ... For other uses, see Root (disambiguation). ... Stem showing internode and nodes plus leaf petiole and new stem rising from node. ... Stoma of a leaf under a microscope. ... Cross section of celery stalk, showing vascular bundles, which include both phloem and xylem. ... For other uses, see Wood (disambiguation). ... For the scientific journal see The Plant Cell. ... Plant cells separated by transparent cell walls. ... Chlorophyll is a green pigment found in most plants, algae, and cyanobacteria. ... Chloroplasts are organelles found in plant cells and eukaryotic algae that conduct photosynthesis. ... The leaf is the primary site of photosynthesis in plants. ... Plant hormones (also known as plant growth regulators (PGRs) and phytohormones) are chemicals that regulate a plants growth. ... Plant cells with visible chloroplasts. ... Transpiration is the evaporation of excess water from aerial parts and of plants, especially leaves but also stems, flowers and fruits. ... Sporic or diplohaplontic life cycle. ... In plants that undergo alternation of generations, a gametophyte is the structure, or phase of life, that contains only half of the total complement of chromosomes: The sporophyte produces spores, in a process called meiosis. ... Close-up of an Echinopsis spachiana flower, showing both carpels and stamen, making it a complete flower. ... SEM image of pollen grains from a variety of common plants: sunflower (Helianthus annuus), morning glory (Ipomoea purpurea), prairie hollyhock (Sidalcea malviflora), oriental lily (Lilium auratum), evening primrose (Oenothera fruticosa), and castor bean (Ricinus communis). ... Carpenter bee with pollen collected from Night-blooming cereus Pollination is an important step in the reproduction of seed plants: the transfer of pollen grains (male gametes) to the plant carpel, the structure that contains the ovule (female gamete). ... A ripe red jalapeño cut open to show the seeds For other uses, see Seed (disambiguation). ... This article or section is in need of attention from an expert on the subject. ... Young sporophytes of the common moss Tortula muralis. ... Plant taxonomy is the science that finds, describes, classifies and names plants. ... A botanical name is a formal name conforming to the ICBN. As with its zoological and bacterial equivalents it may also be called a scientific name. Botanical names may be in one part (genus and above), two parts (species) or three parts (below the rank of species). ... Botanical nomenclature Plants are given formal names, governed by the ICBN. Within the limits set by the ICBN there is a separate set of rules, the ICNCP, for those plants in cultivation that require separate recognition, so-called cultivars. ... In Botany, a herbarium is a collection of preserved plants or plant parts, mainly in a dried form. ... The International Association for Plant Taxonomy (IAPT) is devoted to plant systematics, taxonomy and nomenclature. ... The International Code of Botanical Nomenclature (ICBN) is the set of rules that governs plant nomenclature, i. ... Writing the Species Plantarum was one of Carolus Linnaeus two great contributions to the Scientific community. ...


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