stem |
> cane, culm |
STRUCTURE |
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The entire axial system of a shoot, or a component, primary or higher-order (branch) axis of the shoot; differentiated anatomically and morphologically into nodes and internodes, from the former of which it branches exogenously and bears leaves, bracts, and/or inflorescences; usually growing above ground level, but sometimes structurally and functionally specialized and growing underground (e.g., rhizome, tuber) or upon the surface of the ground (e.g., stolon). Although sometimes phenotypically distinctive and often treated separately for descriptive purposes, the axial system of an inflorescence, excluding pedicels or parts of them in some cases, is properly stem in the above general sense. |
pseudolamina pl. pseudolaminae |
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STRUCTURE |
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The expanded part of a phyllode (phyllodium), resembling a blade but evolutionarily derived from the petiole. |
blade |
= lamina |
STRUCTURE |
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The expanded, more or less planate, distal portion, when present, of a leaf, leaflet or bract. |
lamina 1 pl. laminae |
= blade |
STRUCTURE |
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The expanded, more or less planate, distal portion, when present, of a leaf, leaflet or bract. |
wall (fruit, ovary, pollen, spore) |
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STRUCTURE |
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The exterior layer of tissue(s) enclosing anatomically distinct interior tissues and sometimes fluid and/or one or more cavities. |
surface |
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FEATURE |
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The exterior or bounding area or layer of any structure, regarded as being infinitely thin; usually described as to relief, reflectance, and/or vesture. |
throat 1 |
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STRUCTURE |
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The far distal portion of a perianth, calyx, or corolla tube, or of a leaf sheath, surrounding the orifice of the tube or sheath, sometimes constricted relative to the diameter of the main body of the tube or sheath; except in disc florets of Asteraceae (Compositae). |
anther |
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STRUCTURE |
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The fertile, loculate, pollen-bearing portion of a stamen, containing one, two, or four thecae (pollen sacs), when that portion is differentiated from and borne at the summit of a narrower supporting stalk (filament), or when such differentiation is deemed to have occurred in the evolutionary past with subsequent reduction of the filament (the anther then sessile and constituting the entirety of the stamen). |
collar 1 |
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STRUCTURE |
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The free portion (if any) of a floral tube, distal to its casing and/or neck when one or both is/are present. |
throat 2 |
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STRUCTURE |
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The fully connate portion of the limb of a disc floret, proximal to the lobes (distinct distal portions of the petals); in Asteraceae (Compositae). |
pyrene 1 |
= stone |
STRUCTURE |
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The hard inner portion of a drupe, consisting of osseous endocarp and included seed. |
stone |
= pyrene |
STRUCTURE |
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The hard inner portion of a drupe, consisting of osseous endocarp and included seed. |
pyrene 2 |
= stone |
STRUCTURE |
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The hard seed of a drupelet; esp. in Rosaceae. |
beak 2 |
= rostrum |
STRUCTURE |
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The inner, horn-like segment of a coronal lobe; esp. in Asclepiadaceae. |
rostrum 2 pl. rostra |
= beak |
STRUCTURE |
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The inner, horn-like segment of a coronal lobe; esp. in Asclepiadaceae. |
endocarp |
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STRUCTURE |
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The innermost tissue layer of a pericarp. |
collar 2 |
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FEATURE |
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The junction between the sheath and blade of a leaf; esp. in Poaceae (Gramineae). |
sheath (leaf) |
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STRUCTURE |
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The lower (basal or proximal), fundamentally laminar but strongly involute portion of one of the non-petiolate leaves characteristic of most monocotyledons (Liliidae); distinct from the leaf blade, which, when present, is borne distally upon it; analogous, though not necessarily homologous, with a petiole; usually more or less completely enclosing a portion of the stem above the node from which the leaf is borne. |
first glume |
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STRUCTURE |
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The lower (proximal) or sometimes solitary small bract inserted at the base of a grass (Poaceae) spikelet, the second glume, when present, inserted immediately above (distal to) it. |
palate |
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STRUCTURE |
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The lower, prominent labium (lip) of a personate (gaping, ringent) corolla. |
thallus 2 pl. thalli |
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STRUCTURE |
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The main body of a gametophyte, bearing rhizoids, gametangia (antheridia and/or archegonia), and/or gemmae cups; usually thin and more or less planate, inconspicuous, and growing appressed to or beneath the substrate surface; in Psilotophyta, Lycopodiophyta, Equisetophyta, Polypodiophyta. See also prothallus. |
gametophyte |
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PLANT |
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The main, ultimate, gamete-bearing stage in the haploid (n chromosomes) phase of a taxon's life cycle. Two morphologically and genetically distinct and alternate stages together constitute the complete life cycle in sexually reproducing taxa, the other phase (sporophytic) being diploid (2n chromosomes). Any taxon whose life cycle is confined to one or the other phase is limited to asexual means of reproduction, since sexual reproduction and consequent genetic recombination are impossible without alternation between haploid and diploid states via meiosis and fertilization. The term gametophytic applies to any part of the haploid phase, including all unicellular to multicellular entities belonging to it, whereas gametophyte is reserved for the principal and directly gamete-producing stage of that phase. In all vascular plant taxa the sporophyte is the dominant and most conspicuous phase of the life cycle. The gametophytes of "lower" vascular plants (ferns and "fern-allies") are physically independent of the sporophytes and, though inconspicuous, merit description in their own rights. Those of gymnosperms and angiosperms are minute and physically dependent upon (contained within) sporophytic structures and are not usually included in morphological descriptions. In the flowering plants at least, the haploid phase is (presumably evolutionarily) reduced to such a degree that the existence of gametophytes per se is debatable. |
sporophyte |
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PLANT |
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The main, ultimate, spore-bearing stage in the diploid (2n chromosomes) phase of a taxon's life cycle. Two morphologically and genetically distinct and alternate phases together constitute the complete life cycle in sexually reproducing taxa, the other phase (gametophytic) being haploid (n chromosomes). Any taxon whose life cycle is confined to one or the other phase is limited to asexual means of reproduction, since sexual reproduction with consequent genetic recombination is impossible without alternation between haploid and diploid states via meiosis and fertilization. The term sporophytic applies to any part of the diploid phase, including all unicellular to multicellular entities belonging to it, whereas sporophyte is reserved for the principal and directly spore-producing stage of that phase. |
mesocarp |
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STRUCTURE |
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The middle tissue layer of the pericarp of a fruit. |
hilum 2 pl. hila |
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FEATURE |
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The more or less central point within a starch grain of intracellular origin, about which the successive layers of starch were accreted more or less symmetrically. |