The leaf is next to stem axis and the root of one of three basic institutions of higher plants and is known as an organ type Phyllom. Leaf are lateral outgrowths at the nodes (nodes) of stem axis. The original features of leaf are photosynthesis (structure of organic substances by means of light) and transpiration (evaporation of water is important for nutrient uptake and transport) (wholesale Galax leaves).
Lower leaf are also found in rhizomes, underground runners. The scales of onion bulbs are usually low-leaf. The base leaf or leaf base is the lowest part, with the the Journal of stem axis. As axillary refers to angle between the stem axis and it sheet. It is usually only slightly thickened, but sometimes occupies the entire circumference of stem axis. As is known in plants bracts subtending bracts, which carry inir axil a single flower, an inflorescence or part of inflorescence. A bract of a single flower is called wrapper. As bracts is called bracts, which are mostly surrounded several an inflorescence. Your whole shell is called (involucre). The most flowering branch directly to following bract leaf called bracts
In some plant families, such as sweet and sour grasses the leaf base forms a so-called leaf sheath. This is a more or less wide, mostly to be found on the base leaf, like a sheath surrounding the stem axis part. In most cases, this vagina is split, ie, the edges are free to set only one above the other. In contrast, the leaf of Sedge closed sheaths or those in which no free edges are present. But many leaf of vaginal portion is only hinted at or absent.
The stipules are lateral, zipfel- or sheet-like outgrowths Leaf bases. They are usually small, in many plant species are absent or already dropped the leaf emerge. Depending on the construction of petiole occur in two ways. In petiole occur who always sit in pairs side leaf base. This form is characteristic of dicots. In petiole occur on median (axillary) stipules that occur only in singular and lie in medians in axil leaf. They are often hood-shaped and occur mainly in monocots.
When two lines or couplets leaf position at each node is only one leaf, leaf consecutive nodes are shifted by 180, thus yielding to stem axis, two longitudinal rows of leaf. Representatives are many monocots and Legume. At constant exchange blade position is also located only one sheet at each node, the angle between two sheets but is different from 180 degrees, the leaf are along a spiral line. This arrangement is characteristic of dicotyledonous plants. When compared basal leaf position, two leaf at each node. When dekussierten or decussate phyllotaxis successive leaf pairs are rotated by 90 degrees, so above the other at right angles. It created four longitudinal rows. Representatives are mint, clove plants and Oleaceae.
The palisade parenchyma consists of one to three layers of elongated, upright to sheet surface, cells. The palisade parenchyma, whose main task is photosynthesis, there are about 80 percent of all chloroplasts. The spongy parenchyma consists of irregularly shaped cells that form large intercellular spaces because ofir shape. The main task of spongy parenchyma is to ensure the ventilation of parenchymal tissue. The cells are relatively low in chloroplasts.
The bundles are often located on the border between palisade and spongy parenchyma in upper spongy parenchyma. The structure resembles that of bundles in stem axis and is usually collateral. The bundles branch off from the stem axis and go through the leaf stalk without rotation in lamina over. As a result, the xylem to leaf surface, the phloem to lower leaf surface.
The petiole (petiole) is the following on the leaf base, more or less through its narrow stalk shape from the following part leaf sharply defined part leaf. According to anatomical structure, a distinction bifacial and petioles. In most monocots and many conifers, petiole absent. Leaf without stem are called sessile. There is also leaf, which consist only of stem, which is then flat and wide and on which the actual blade surface is entirely lacking. This is a so-called leaf petiole (Phyllodium), z. B. In some acacias. The petiole is usually formed only in leaf.
Lower leaf are also found in rhizomes, underground runners. The scales of onion bulbs are usually low-leaf. The base leaf or leaf base is the lowest part, with the the Journal of stem axis. As axillary refers to angle between the stem axis and it sheet. It is usually only slightly thickened, but sometimes occupies the entire circumference of stem axis. As is known in plants bracts subtending bracts, which carry inir axil a single flower, an inflorescence or part of inflorescence. A bract of a single flower is called wrapper. As bracts is called bracts, which are mostly surrounded several an inflorescence. Your whole shell is called (involucre). The most flowering branch directly to following bract leaf called bracts
In some plant families, such as sweet and sour grasses the leaf base forms a so-called leaf sheath. This is a more or less wide, mostly to be found on the base leaf, like a sheath surrounding the stem axis part. In most cases, this vagina is split, ie, the edges are free to set only one above the other. In contrast, the leaf of Sedge closed sheaths or those in which no free edges are present. But many leaf of vaginal portion is only hinted at or absent.
The stipules are lateral, zipfel- or sheet-like outgrowths Leaf bases. They are usually small, in many plant species are absent or already dropped the leaf emerge. Depending on the construction of petiole occur in two ways. In petiole occur who always sit in pairs side leaf base. This form is characteristic of dicots. In petiole occur on median (axillary) stipules that occur only in singular and lie in medians in axil leaf. They are often hood-shaped and occur mainly in monocots.
When two lines or couplets leaf position at each node is only one leaf, leaf consecutive nodes are shifted by 180, thus yielding to stem axis, two longitudinal rows of leaf. Representatives are many monocots and Legume. At constant exchange blade position is also located only one sheet at each node, the angle between two sheets but is different from 180 degrees, the leaf are along a spiral line. This arrangement is characteristic of dicotyledonous plants. When compared basal leaf position, two leaf at each node. When dekussierten or decussate phyllotaxis successive leaf pairs are rotated by 90 degrees, so above the other at right angles. It created four longitudinal rows. Representatives are mint, clove plants and Oleaceae.
The palisade parenchyma consists of one to three layers of elongated, upright to sheet surface, cells. The palisade parenchyma, whose main task is photosynthesis, there are about 80 percent of all chloroplasts. The spongy parenchyma consists of irregularly shaped cells that form large intercellular spaces because ofir shape. The main task of spongy parenchyma is to ensure the ventilation of parenchymal tissue. The cells are relatively low in chloroplasts.
The bundles are often located on the border between palisade and spongy parenchyma in upper spongy parenchyma. The structure resembles that of bundles in stem axis and is usually collateral. The bundles branch off from the stem axis and go through the leaf stalk without rotation in lamina over. As a result, the xylem to leaf surface, the phloem to lower leaf surface.
The petiole (petiole) is the following on the leaf base, more or less through its narrow stalk shape from the following part leaf sharply defined part leaf. According to anatomical structure, a distinction bifacial and petioles. In most monocots and many conifers, petiole absent. Leaf without stem are called sessile. There is also leaf, which consist only of stem, which is then flat and wide and on which the actual blade surface is entirely lacking. This is a so-called leaf petiole (Phyllodium), z. B. In some acacias. The petiole is usually formed only in leaf.
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