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pollinium pl. pollinia |
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STRUCTURE |
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A mass of coherent pollen grains disseminated as a unit by adhering to a pollinating insect, representing the entire content of a single theca or of fused thecae; often distally attenuate to a sterile caudicle (translator arm), which may attach to a viscidium, either directly or through an intervening stipe; esp. in Asclepiadaceae, Orchidaceae. |
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pollinial |
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arrangement |
pollen |
Polyadal with the grains of individual thecae (pollen sacs), or of fused thecae, compacted and forming tightly coherent masses (pollinia) that constitute the basic dispersal units, these sometimes distally attenuate to a sterile caudicle (translator arm), sometimes united by caudicles in groups of two or more, the caudicle(s) sometimes attached to a viscidium, either directly or through an intervening stipe; esp. in Asclepiadaceae, Orchidaceae. |
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pollinarium pl. pollinaria |
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STRUCTURE |
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A pollinium together with, when present, its stipe and viscidium; the entire unit of pollinium dispersal. |
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pollen sac |
= theca |
STRUCTURE |
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Any of the one, two or four ontogenetically distinct, pollen-producing sectors (microsporangia) of an anther. In some taxa the walls between pairs of adjacent thecae break down as an anther approaches maturity, the mature anther thus ultimately containing half as many locules as thecae. |
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pollen |
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STRUCTURE |
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Collectively, the spores or grains produced within the thecae of anthers, each containing a very small microgametophyte (or its evolutionary homologue); serving as disseminules from which microgametes are released after transport to a receptive micropylar pollen droplet (in Pinophyta) or stigma (in Magnoliophyta) by a variety of vectors, notably wind, water, insects, bats, and birds. |
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polished |
= glossy, laevigate, lustrous, shining, shiny |
reflectance |
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Uniformly reflecting a high proportion of incident light at all angles. |
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pneumatophore |
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STRUCTURE |
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A structurally and functionally specialized root serving as an aboveground aerating organ; found in some woody taxa of wet habitats, notably some mangroves. |
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pluri… |
= many-…, multi…, poly… |
prefix |
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Indicating presence of or constitution by a relatively large number of entities of the type denoted by the term's stem; as in plurilocular, pluriseriate. See also oligo… (few-…). |
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plumule |
= epicotyl |
STRUCTURE |
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A distinguishable nascent shoot developed in the embryo in some taxa, consisting of a shoot axis with unexpanded internodes and one or more leaf primordia, being that portion of the embryo above the level of cotyledon insertion; the primordial shoot, when developed by the embryo within a seed; the first bud of a spermatophyte, when developed by an embryo within the seed. In other taxa the shoot is represented in the embryo only by a quiescent apical meristem at the summit of the embryonic axis. |
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plumose |
= feather-shaped |
solid shape |
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Having a slender central axis bearing two opposite ranks of numerous, closely proximate, ascending, very slender branches or appendages; resembling the generalized form of a feather. |
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pliestesial |
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duration |
plant |
Perennial and monocarpic, living several to many years before reproducing sexually, dying promptly thereafter. |
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plicate 3 |
= plaited, pleated |
vernation |
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Having alternately adaxial and abaxial lengthwise folds, resembling a closed fan. |
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plicate 2 |
= plaited, pleated |
solid shape |
foliaceous structure |
Having alternately adaxial and abaxial lengthwise folds, resembling a fan. |
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plicate 1 |
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aestivation |
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Valvate with each member strongly infolded longitudinally. |
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pliant |
= flexible, pliable, supple |
texture |
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Able to bend over its length and/or breadth without structural disruption. |
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pliable |
= flexible, pliant, supple |
texture |
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Able to bend over its length and/or breadth without structural disruption. |
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pleurorhizal |
= accumbent |
arrangement |
cotyledons |
Having the two cotyledons facing and parallel (adaxial surfaces contiguous) and recurved together, one lateral edge of each abutting the hypocotyl and radicle. |
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pleated 2 |
= plaited, plicate |
vernation |
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Having alternately adaxial and abaxial lengthwise folds, resembling a closed fan. |
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pleated 1 |
= plaited, plicate |
solid shape |
foliaceous structure |
Having alternately adaxial and abaxial lengthwise folds, resembling a fan. |
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platter-shaped |
= scutellate, scutelliform |
solid shape |
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Relatively thin with opposite broad oval faces, shallowly concave-convex; like a serving platter. See also buckler-shaped (scutate, scutiform), which is not clearly distinct in its application. |
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plated |
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relief |
bark |
Fissured in a more or less regular, anastomosing pattern with distinct, relatively large, undisturbed sectors intervening, the latter ultimately falling away more or less intact after attaining considerable thickness. |
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plantlet |
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STRUCTURE |
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A juvenile, complete plant produced asexually by budding, as from the leaf margin in some Kalanchoë (Crassulaceae); this term is usually applied only while such vegetatively produced offspring remain attached to the plant of origin. |
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planoconvex |
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solid shape |
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Relatively thin with opposite broad faces, one plane and one convex. |
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planoconcave |
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solid shape |
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Relatively thin with opposite broad faces, one plane and one concave. |
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plane shape |
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CHARACTER |
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Overall two-dimensional form or aspect(s) thereof. Overlaps conceptually with architecture, arrangement, habit, insertion, orientation, and position. |
