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Photosynthate
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The carbohydrates produced by photosynthesis. |
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Photosynthesis
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The process by which green plants produce carbohydrates from carbon dioxide and water utilizing radiant energy from the sun. |
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Photosynthetic bark
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Refers to bark that harbors chlorophyll which gives at least some of the bark a green color. Most often plants with photosynthetic bark drop their leaves (are deciduous) at a certain time of year and whatever photosynthesis that takes place at that time is within the bark chlorophyll. Usually trees of species with photosynthetic bark grow under environmental stress at certain times of the year, e.g., during the dry season or when river levels rise and water covers the lower part of the trunk |
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Photosynthetic stems
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Stems that harbor chlorophyll which gives them a green color. Often plants with photosynthetic stems drop their leaves (are deciduous) at a certain time of year and whatever photosynthesis that takes place at that time is within the stem chlorophyll. Usually plants with photosynthetic stems grow under environmental stress at certain times of the year, e.g., extremely dry periods during which considerable evapotranspiration would take place if the leaves were retained. |
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Phyllary (plural = phyllaries)
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One of a series of overlapping bracts that subtends the capitulum (head) of Asteraceae. |
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Phylloclade
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A branch that has taken on the form and function of a leaf. |
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Phyllode
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A petiole and or rachis that has taken on the form and function of a leaf; e.g., in certain species of Acacia. |
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Pilose (diminutive = pilosulous)
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A covering of long, soft, simple trichomes. |
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Pin flower
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One of two types of flowers found in some species in which the style is long and the stamens are short. Compare with thrum flower; see heterostyly. |
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Pinnate
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Feather-like; generally referring to the arrangement of veins along a midrib of a leaf blade or to leaflets along a rachis in a way that resembles the structure of a feather. |
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Pinnate (pinnately compound leaves)
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Bearing leaflets along a common axis or rachis. See paripinnate and imparipinnate. |
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Pinnate venation
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A type of venation pattern in which the secondary veins run parallel to each other from the midrib toward the margin. |
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Pinnately veined
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Bearing the secondary veins along both sides and for the length of the midrib (primary vein). |
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Pinnule
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A secondary or higher division of a compound leaf of ferns, in this example the marked pinnule is a primary pinnule which makes up the primary pinnule which, in turn, makes up the frond. |
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Pioneer
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A species of plant that colonizes a deforested, barren, or disturbed area; e.g., many species of Cecropia (Cecropiaceae) are pioneer plants. |
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Pistil
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The female part of the flower composed of the ovary, style, and stigma. |
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Pistillate flower
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Referring to unisexual flowers with functional gynoecia but without functional stamens (staminodes may be present). Same as female flower. |
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Pistillate phase
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Refers to species with bisexual flowers that release pollen and have receptive stigmas at different times over the course of floweirng, the pistillate phase is when the stigmas are receptive and the anthers either have or will release their pollen. This serves as a mechanism that promotes outcrossing, especially when the different phases are synchronous on the same plant. |
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Pith
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The spongy ground tissue occupying the center of many stems. |
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Placenta (pl. = placentae)
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The tissue within an ovary to which the ovules are attached or closely associated. |
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Placenta (plural = placentae)
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The structure in the ovary to which the ovules are attached. |
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Placenta arched
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A type of placentation in which the placenta arches from the top of the lower septum and gets progressively thicker toward the base as seen in medial longitudinal section. |
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Placenta columnar
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A type of placentation in which the lower septum is only slightly expanded more-or-less equally throughout its length as seen in a medial longitudinal section. |
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Placenta flabellate
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A type of placenta in which the ovules are inserted on placenta tissue that fans outward from the lower septum as viewed in medial longitudinal section. |
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Placenta incipient
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A type of placenta which is barely expanded from the septum as seen in medial longitudinal section. |
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