Epidermal stem cell

Epidermal cells Tabular are layered sheets on surfaces of leaves and young roots, stems, flowers, fruits, seeds, ovules Secrete the fatty substance, cutin, which forms a protective layer, the cuticle cuticle covered by an epicuticular wax... 

Feruloylated pectins have been found in the parenchymatous cell walls of many Dicotyledons (mainly in the Centrospermae and Solanaceae), but UV-fluorescence microscopy suggests that at least the epidermal cell walls of all Dicotyledons contain phenolic residues it remains to be seen whether these phenolic residues are attached to polysaccharides or to cutin, but location of even a small quantity of, say, feruloyl-pectin in the epidermal wall would be particularly significant in the control of growth because the extensibility of the epidermis controls the expansion of whole stems (23) and leaves (Fry, unpublished observations). The extensins, as already mentioned, are rich in the phenolic amino acid tyrosine (2). 

Epidermis is the outer covering tissue of a plant and is protective in function. Its cells may be brick-shaped, polygonal, equilateral or wavy in outline. Their outer walls are frequently lutinized (infiltrated with a waxy-like substance called cutin). Among the epidermal cells of leaves and young green stems may be found numerous pores or stomata (sing, stoma) surrounded by pairs of crescent-... 

The epidermis of leaves, stems, fruits, and seeds of many plants frequently give rise to outgrowths in the form of papillae, hairs and scales. Epidermal papilla are short protuberances of epidermal cells. They may be seen to advantage on the upper epidermis of the... 

Acanthaceae or Acanthus Family.—Usually herbaceous Ruellia), rarely sub-woody or woody plants, occasionally bushy in habit, containing cystoliths in the mesophyll or epidermal cells of the leaves and in the parenchyma of the roots and stems. Leaves opposite. 

Bloom.—The whitish and waxy secretion of epidermal cells, as in the stems of Sugar Cane or the leaves.of Cabbage. 

Microbial 3-Glucan Hydrolases and Lysis of Plant Cell Wall Polymers. Many soil and aerial pathogens gain access to host tissues by enzymic lysis of epidermal cell walls of roots, leaves, stems, etc.. Phytopathogenic organisms possess an array of inducible polysaccharide hydrolases capable of degrading the complex polysaccharides of the plant cell wall (, 10). The... 

The epidermis is a designation of location rather than type of cells. The epidermal layer of vertebrates, which is the outer layer of skin, is usually made up of stratified epithelium with an outer layer of dead cells and an inner layer of growing and dividing cells. The invertebrate epidermis is normally one cell thick and often forms a protective cuticle (Hale et al., 1995). The epidermis of plants is a one-ceU thick tissue that surrounds young roots, stems, and leaves. The epidermal cells (not epithelium) of stems and leaves secrete a cuticle (a protective layer of protein or lipids). 

Quinolizidine alkaloids are accumulated in the epidermal cells of leaves, petioles, and stems. These plant parts often contain as much as 5-6 mg/g fresh weight. Although the alkaloids are accumulated in the epidermis, they are synthesized in chloroplasts of mesophyll cells. Specific mechanisms for movement of the alkaloids into the vacuoles of the epidermal cells appear to involve carrier proteins (Mende and Wink, 1987 Wink, 1985b). 

Anthocyanins are present in different plant organs, such as fruits, flowers, stems, leaves, and roots [16]. These pigments are normally found dissolved uniformly in the vacuolar solution of epidermal cells. However, in certain species, the anthocy-anins are localized in discrete regions of the cell vacuole, called anthocyanoplasts [17]. The main sources of anthocyanin (Table 58.1) are red fruits, maiifly berries and red grapes cereals, principally purple maize and red-purple and vegetables such as eggplant [6, 18]. 

Reynolds AJ, Jahoda CA (1991) Hair follicle stem cells A distinct germinative epidermal cell population is activated in vitro by the presence of hair dermal papilla cells. J Cell Sci 99(2) 373-385... 

Auxins stimulate the elongation of stem and coleoptile cells within 10 to 20 min of application (Evans 1974). This is accompanied by enhancement of wall biosynthesis, wall loosening, and ion secretion (Evans 1974). Stimulation of elongation by auxin occurs in hypocotyl, epicotyl, and stem cells of a wide variety of dicots (Cleland et al. 1968, Barkley and Evans 1970, Audus 1972, Kazama and Katsumi 1973), and in the coleoptiles of all of the grasses that have been examined (Audus 1972, Evans 1974). The epidermal cells of seedling stems and hypocotyls are most responsive to auxin and may, in large measure, control the growth response to this hormone (Masuda and Yamamoto 1972). 

Lawton J R 1980 Observations on the structure of epidermal cells, particularly the cork and silica cells, from the flowering stem internode of Lolium emulentum L. (Gramineae). Bot J Linn Soc 80 161-177... 

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