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neck (archegonial) |
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STRUCTURE |
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The distal narrowed portion of an archegonium above its bulbous base. |
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hypogynium pl. hypogynia |
= gynophore; < stalk, stipe (broad sense, not recommended) |
STRUCTURE |
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The basal portion of an ovary when constricted and stalk-like above the level of perianth insertion, bearing the main body of the pistil at its summit; in Cyperaceae. |
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prickle |
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STRUCTURE |
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Any unvascularized spine-like enation originating in the epidermis, cortex, or mesophyll of any shoot part. See also spine, thorn. |
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bracteole 1 |
= bractlet; < bract |
STRUCTURE |
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A diminutive bract, or a bract that is smaller than others present. |
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dyad |
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STRUCTURE |
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A pair of coherent pollen grains shed as a unit. |
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carpophore 3 |
= columella; < stalk |
STRUCTURE |
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The stalk supporting a mericarp after dehiscence of a schizocarpic fruit, the central axis of the fruit having split longitudinally to yield two or four such stalks; composed of receptacular and (primarily) gynoecial tissues; esp. in Apiaceae (Umbelliferae). |
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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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mesochilium |
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STRUCTURE |
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The central portion of a labellum (lip) that has distinct proximal, distal, and central parts; in Orchidaceae. See also epichilium, hypochilium. |
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sorus pl. sori |
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STRUCTURE |
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A cluster of sporangia borne upon a fertile frond, usually on its abaxial surface; often covered during maturation by a protective membrane, the indusium, that is an outgrowth from the epidermis; in Polypodiophyta. |
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crozier |
= fiddlehead |
STRUCTURE |
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A circinate leaf (frond) prior to full expansion, while still wholly or distally coiled; esp. in Polypodiophyta. |
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pith |
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STRUCTURE |
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The central ground tissue of a stem or, when present, of a root, consisting of thin-walled parenchyma cells; distinct and more or less soft and spongy relative to the other tissues of the axis; sometimes partly or wholly degenerating after secondary growth has begun. |
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torus 2 pl. tori |
= receptacle |
STRUCTURE |
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The short, expanded, compound axial structure surmounting a peduncle and basal to two or more flowers, or to the florets of a capitulum (head) in Asteraceae (Compositae), where it may bear paleae (receptacular bracts), scales, bristles, trichomes, or subulate enations, and may be smooth or variously pitted (alveolate, foveolate). |
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coleorhiza |
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STRUCTURE |
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A sheath-like structure enclosing the radicle (embryonic root) in an embryo; esp. in Poaceae (Gramineae). |
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embryo sac |
< megagametophyte |
STRUCTURE |
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The multinucleate generative cell of an ovule, within which fertilization and zygote formation occur; resulting from meiotic division of a megaspore mother cell within the nucellus, and thus genetically haploid; its contents generally considered to represent an evolutionarily reduced gametophyte. |
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neck (floral tube) |
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STRUCTURE |
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The solid, usually constricted portion of a floral tube sometimes present between casing and collar when those are both present. |
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cotyledon |
= seed leaf |
STRUCTURE |
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Any of the one or more primary foliar structures of an embryonic seed plant, proximal to all succeeding leaf primordia; sometimes serving as a storage organ for food reserves in the seed, as in peas and beans. |
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petiole |
< stalk, stipe (broad sense, not recommended) |
STRUCTURE |
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The stalk, when present, of a leaf. |
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thallus 1 pl. thalli |
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STRUCTURE |
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The vegetative portion of a shoot when not differentiated into stem and leaves; esp. in Lemnaceae. |
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cladode |
= cladophyll, phylloclade |
STRUCTURE |
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A stem segment that functions as a leaf; often more or less compressed. |
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operculum pl. opercula |
= lid |
STRUCTURE |
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A distal, cover-like portion of a structure whose main body is otherwise closed, transversely discontinuous with the main body around most of the circumference, or becoming partially or wholly separate by transverse dehiscence; as of an ascidium (pitcher), pollen grain, pyxis, or sporangium (spore case). |
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twig |
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STRUCTURE |
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The terminal portion of an ultimate branch of a woody stem, representing the most recent increment of growth and bearing or having borne the current or most recent increment of leaves. See also branchlet. |
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seta 1 pl. setae |
= arista, awn, bristle |
STRUCTURE |
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A slender, more or less straight and stiff, fine-pointed, terminal or subterminal appendage or prolongation, sometimes a continuation of the bearing structure's central primary vein, as on a glume, lemma, or palea in Poaceae (Gramineae). |
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bracteole 2 |
= bractlet, prophyll(um); < bract |
STRUCTURE |
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A second- or higher-order bract within, and subtending some portion of, an aggregate branching structure, especially when subtending a flower. |
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bractlet 1 |
= bracteole; < bract |
STRUCTURE |
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A diminutive bract, or a bract that is smaller than others present. |
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limb 1 |
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STRUCTURE |
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A relatively broad portion of a syntepalous (gamotepalous) perianth, synsepalous (gamosepalous) calyx, or sympetalous (gamopetalous) corolla distal to a narrower tube, spreading outward or ascending from the tube, comprising the distinct or connate distal portions of the tepals, sepals, or petals; except in bisexual or staminate disc florets of Asteraceae (Compositae). |
