gland |
> nectary |
STRUCTURE |
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An anatomically distinct multicellular structure that produces and exudes a particular substance, or resembles those that do. |
cross-vein |
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STRUCTURE |
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A relatively short, secondary or higher-order vein that runs directly between two veins of the next lower order, intersecting them more or less perpendicularly. |
articulation |
= joint |
STRUCTURE |
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A distinct, relatively narrow zone of demarcation between adjacent main portions of an elongate structure, often thicker than the rest of the structure and sometimes a site of eventual abscission. |
bole |
= trunk; < main stem, primary stem |
STRUCTURE |
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The relatively stout, columnar, main stem of a distinct aboveground portion of a tree. |
column foot |
= mentum |
STRUCTURE |
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A lateral, often nectariferous protrusion from the proximal portion of a column, opposite the labellum, projecting in front of the rest of the flower; in Orchidaceae. |
diffuse root |
> fibrous root |
STRUCTURE |
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Any member of a dense system of adventitious, slender roots that arise from the base of a main stem and functionally replace an evanescent primary root. |
palet 1 |
= pale, palea, receptacular bract |
STRUCTURE |
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A small papery (chartaceous) to membranous bract borne on the compound receptacle (torus) of a capitulum (head) in Asteraceae (Compositae). |
carina 1 pl. carinae |
= keel |
STRUCTURE |
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An elongate, median longitudinal ridge that is basically triangular in transverse section and resembles the keel of a boat; esp. in leaf blades and sheaths, glumes, lemmata, paleae, sepals, petals. |
indusium pl. indusia |
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STRUCTURE |
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A protective membrane that is an outgrowth from the epidermis and covers a sorus during its maturation; in Polypodiophyta. |
sucker |
> turion |
STRUCTURE |
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A shoot arising adventitiously from a root or stem below or at ground level. |
costule |
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STRUCTURE |
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A longitudinal primary vein in a diminutive laminar structure, such as the blade of a leaflet, pinna or pinnule; a diminutive costa (rib). |
lamina 2 pl. laminae |
= ray |
STRUCTURE |
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The distal, relatively flat portion of the zygomorphic corolla of a ray floret, terminating in 0--4 teeth or lobes; in Asteraceae (Compositae). |
sapwood |
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STRUCTURE |
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That portion of the wood (xylem) of a stem or root whose cells are still living and functional; concentric about the heartwood once the latter has begun to form. |
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. |
bud scale |
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STRUCTURE |
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A scale that, alone or aggregated with others, envelops and protects a bud. |
vascular bundle |
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STRUCTURE |
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A discrete strand of conducting tissues (xylem, phloem) and associated cells (e.g., cambium) within a stem or other axial structure. |
nucellus pl. nucelli |
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STRUCTURE |
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The distinct, genetically diploid tissue layer immediately surrounding the embryo sac of an ovule; often considered equivalent to a megasporangium wall. |
coma pl. comae, comas |
< tuft |
STRUCTURE |
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A prominent single tuft of relatively long and slender, flexible, capillate trichomes; esp. from a seed, as in Asclepias (Asclepiadaceae). |
palet 2 |
= pale, palea |
STRUCTURE |
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The upper or distal of the (usually) two distinctive bracts immediately subtending the flower in a grass (Poaceae) spikelet. |
carina 2 pl. carinae |
= keel |
STRUCTURE |
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Collectively, the two relatively small, connate or coherent, abaxial (lower) petals that form the keel-like portion of a papilionaceous corolla. |
embryo |
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STRUCTURE |
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The rudimentary spermatophyte contained within a viable seed. |
neck (archegonial) |
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STRUCTURE |
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The distal narrowed portion of an archegonium above its bulbous base. |
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. |
beak 1 |
= rostrum |
STRUCTURE |
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A relatively long, tapering, more or less rigid and pointed enation or termination. |
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. |