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).
The bundles are popular mostly referred to as nerves or veins, both misleading term, since the bundles still have a circulatory function neither. There are three types of veins that have a systematic significance. In monocots. Here the main veins running along and parallel to each other. This provides the most smooth leaf margin of monocots.
This is particularly evident in grasses. The main veins and also the many smaller parallel bundles are associated with each other by small, usually visible to naked eye bundles (transverse anastomoses). The parallel arrangement of bundles also leads to a parallel arrangement of stomata.
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.
In some families, the stipules are highly developed, as in pea family (such as the pea), the rose family and violet plants. You can either free (z. B. Vetches) or apparently the petiole be grown (roses).
For a number of trees such as lime, hornbeam poplar and the stipules are designed as membranous, not green scales, which already fall during the unfolding leaf. In the stipules are transformed to an extension leaf sheath (Ochrea), a membranous sheath that encloses the stem tubular. The ligule (ligule) of sweet and sour grasses that sits at the junction leaf sheath in leaf blade is also a by-sheet.
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 shape of blade or flake: Specifies whether the sheet, for example, is round, elliptical, linear, kidney-shaped, etc. Leaf describes how leaf blade enters the petiole. Eg, heart-shaped, arrow-shaped. The spreading-Apex (peak), rounded, be sharp, dull, etc. From the Journal of plant leaf hump develops, it differentiates itself by a constriction in a wide proximal portion, the bottom sheet, and a narrow distal portion, the top sheet. Growth occurs only for a short time with the point. The tip is very early in their growth, the growth is by intercalary meristems or basal (untercalary growth).
The bundles are popular mostly referred to as nerves or veins, both misleading term, since the bundles still have a circulatory function neither. There are three types of veins that have a systematic significance. In monocots. Here the main veins running along and parallel to each other. This provides the most smooth leaf margin of monocots.
This is particularly evident in grasses. The main veins and also the many smaller parallel bundles are associated with each other by small, usually visible to naked eye bundles (transverse anastomoses). The parallel arrangement of bundles also leads to a parallel arrangement of stomata.
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.
In some families, the stipules are highly developed, as in pea family (such as the pea), the rose family and violet plants. You can either free (z. B. Vetches) or apparently the petiole be grown (roses).
For a number of trees such as lime, hornbeam poplar and the stipules are designed as membranous, not green scales, which already fall during the unfolding leaf. In the stipules are transformed to an extension leaf sheath (Ochrea), a membranous sheath that encloses the stem tubular. The ligule (ligule) of sweet and sour grasses that sits at the junction leaf sheath in leaf blade is also a by-sheet.
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 shape of blade or flake: Specifies whether the sheet, for example, is round, elliptical, linear, kidney-shaped, etc. Leaf describes how leaf blade enters the petiole. Eg, heart-shaped, arrow-shaped. The spreading-Apex (peak), rounded, be sharp, dull, etc. From the Journal of plant leaf hump develops, it differentiates itself by a constriction in a wide proximal portion, the bottom sheet, and a narrow distal portion, the top sheet. Growth occurs only for a short time with the point. The tip is very early in their growth, the growth is by intercalary meristems or basal (untercalary growth).
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