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Ovules obliquely oriented downward
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Ovules obliquely oriented upward
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Ovules projecting upward at less than right angles from the vertical axis of the ovary. |
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Ovules pendulous
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Ovules that hang downward from the septum at apex of the locule with the micropyle facing upward. |
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Ovules tenuinucellate
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The presence of no cells or a single cell layer between the megasporophyte and the epidermal cells in the early development of the megasporophyte. |
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Ovules tenuinucellate
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The presence of no cells or a single cell layer between the megasporophyte and the epidermal cells in the early development of the megasporophyte. The megasporophyte develops into the embryo sac which contains an egg that, if fertilized and the conditions are right, will develop into an embryo. |
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Oxidation
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The process of using oxygen to break down glucose to obtain energy. This results in the production of carbon dioxide and water as by products. Carbon dioxide and water are also released when forests are burned resulting in the release of greenhouse gases in the atmosphere. |
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Pachycaul
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A type of growth form in which the tree is unbranched (monocaulis) or sparsely branched, the stems are thick, and the leaves very large. |
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Pachycaul
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A type of growth form in which the tree is unbranched (monocaulis) or sparsely branched, the stems are thick, and the leaves very large. |
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Pachycaulous
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Referring to a growth form in which the branching is sparse and the higher-order branches and stems are not markedly diminished in thickness. Compare with leptocaulous. |
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Palea
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The upper of the two bracts that enclose the floret in the Poaceae. Compare with lemma. |
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Palinactinodromous
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Referring to a type of leaf venation in which the primaries have one or more subsidiary points of radiation above the lowest point. |
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Palisade mesophyll
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Referring to one or more layers of cells located directly under the epidermal cells of the adaxial leaf blade surface. The palisade mesophyll is oriented vertically and is longer than broad. Photosynthesis takes place in both palisade and spongy mesophyll. |
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Palmate
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Referring to leaf venation in which the main veins of the blade radiate from a common point near the base or to compound leaves in which all leaflets radiate from a common point. See digitate. palmately lobed, palmatilobate, |
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Palmately veined
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Referring to leaf venation in which the main veins of the blade radiate from a common point near the base. |
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Palmatinervia
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Se refiere a la disposición radial de los nervios que nacen desde un punto común en la base de una hoja |
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Panicle
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A compound raceme in which the primary branches are racemose, which, in turn, give rise to secondary and sometimes higher order racemose branches. |
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Papilionaceous corolla
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The zygomorphic corolla of most species of papilionoid legumes. |
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Papilla (plural = papillae, adj. = papillate)
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Small projections that are often found on leaf blade surfaces. Papillae usually represent modifications of the cuticle. |
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Papilla (plural = papillae; adj. = papillate)
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Referring to an abaxial leaf blade surface or a stigma that bears minute protuberances that appear to be outgrowths of the cuticle of the leaf blade or of the stigma. |
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Papillae
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Minute, rounded protuberances that may cover a surface, e.g., the abaxial leaf blade surfaceae. |
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Pappus
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A modified calyx of hairs, scales, or bristles typical of many Asteraceae. |
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Paracytic stomata
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Referring to a stomatal type in which the two subsidiary cells are parallel to the long axis of the guard cells. The brachyparacytic type is the same as the paracytic type. |
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Paracytic stomata
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Referring to a stomatal type in which the two subsidiary cells are parallel to the long axis of the guard cells. The brachyparacytic type is the same as the paracytic type. |
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Parallel venation
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Generally applied to secondary or higher-order veins that are parallel to each other and to the margins of the leaf, sepal, or petal in which they occur but in monocots they are often numerous primary veins of the same size. |
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Parallelodromous
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Referring to a leaf venation in which there are multiple parallel primary veins that originate at the leaf blade base and converge toward the leaf blade apex. Mostly restricted to monocotyledons. See Ellis et al. 2009 for more detailed descriptions of leaf characters. |
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