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Anatomy of a eudicot leaf The plant cuticle is a layer of lipid polymers impregnated with waxes that is present on the outer surfaces of the primary organs of all vascular land plants. It is also present in the sporophyte generation of hornworts , and in both sporophyte and gametophyte generations of mosses . [ 2 ]
The endodermis is the innermost layer of cortex in land plants. It is a cylinder of compact living cells, the radial walls of which are impregnated with hydrophobic substances (Casparian strip) to restrict apoplastic flow of water to the inside. [1] The endodermis is the boundary between the cortex and the stele.
Land plants maintain adequate tissue hydration by means of an outer waterproof layer. In soft or green tissues, this is usually a waxy cuticle over the outer epidermis.In older, woody tissues, waterproofing chemicals are present in the secondary cell wall that limit or inhibit the flow of water.
As CO 2 was withdrawn from the atmosphere by plants, more water was lost in its capture, and more elegant transport mechanisms evolved. [33] As water transport mechanisms, and waterproof cuticles, evolved, plants could survive without being continually covered by a film of water.
The epidermis is the outermost cell layer of the primary plant body. In some older works the cells of the leaf epidermis have been regarded as specialized parenchyma cells, [1] but the established modern preference has long been to classify the epidermis as dermal tissue, [2] whereas parenchyma is classified as ground tissue. [3]
The root is covered with a special, usually 4- to 5-cell layer thick, [12] spongy tissue (called Velamen), which helps the plant to absorb moisture from the atmosphere. Epiphytic orchid have another sort of root, called clinging roots, that help the orchid plant cling to the substratum (host).
Cross section of celery stalk, showing vascular bundles, which include both phloem and xylem Detail of the vasculature of a bramble leaf Translocation in vascular plants. Vascular tissue is a complex conducting tissue, formed of more than one cell type, found in vascular plants. The primary components of vascular tissue are the xylem and phloem ...
In botany, a stoma (pl.: stomata, from Greek στόμα, "mouth"), also called a stomate (pl.: stomates), is a pore found in the epidermis of leaves, stems, and other organs, that controls the rate of gas exchange between the internal air spaces of the leaf and the atmosphere.