Displaying 1626 - 1700 out of 3058 Object(s)

Per Page

• 25
• 50
• 75

Term	Definition
Lateral vein	Same as secondary vein.
Látex	Exudado blanco, cremoso o amarillo que usualmente emana a través de alguna herida en las plantas. Las especies de Clusiaceae usualmente emanan látex cuando son cortadas
Latex	Opaque, white, creamy, or yellow, free-flowing exudate, usually observed from a wound in a plant; species of Clusiaceae usually exude latex when wounded.
Laticifer	A latex-producing cell or series of cells.
Latrorse	Directed toward the side, as the dehiscence of an anther; same as lateral. Compare with extrorse and introrse.
Latticed	Cross-barred; e.g., the trunks of Swartzia polyphylla (Fabaceae), which are sulcate with connections between the ridges.
Lax	Loose, not congested, often used to describe the density of flowers in an inflorescence.
Leaf	An expanded stucture where photosynthesis takes place and usually consisiting of a petiole and a blade.
Leaf	A green, expanded stucture usually consisiting of a petiole and a blade but sometimes without a petiole in which photosynthesis takes place. When a petiole is absent the leaf is called sessile.
Leaf apex acuminate	Gradually tapering to an acute apex with the sides being concave.
Leaf apex acute	Sharp; usually referring to the apex of a flattened structure (such as a leaf) in which the two sides are straight and, when they meet, form an angle that is always less than 90°
Leaf apex attenuate	Tapering very gradually to a narrow tip.
Leaf apex emarginate	Markedly notched, such as the apex of a leaf or other structure.
Leaf apex mucronate	A sharp point at the apex of a leaf or a similar structure, e.g., a bract.
Leaf apex obtuse	Blunt, usually referring to the apex of a flattened structure (such as a leaf) in which the two sides are straight and, when they meet, form an angle greater than 90°.
Leaf apex retuse	Notched slightly at the apex.
Leaf apex rounded	Referring to a leaf blade base that is curved at the apex with an angle greater than 90 degrees at the point where the two sides meet.
Leaf apex truncate	Referring to an apex or base that terminates abruptly in a nearly straight horizontal edge.
Leaf asymmetrical	Referring to the form of a leaf in relation to the midrib, if the blade on each side of the midrib is unequal the leaf is asymmetrical.
Leaf base acute	Sharp; referring to the base of a leaf blade in which the two sides are straight and, when they meet, form an angle that is always less than 90°.
Leaf base asymmetric	Referring to a leaf base in which the two sides do not attach to the petiole at the same place, one is attached than the other.
Leaf base cordate	Heart-shaped at the base of a leaf blade. A cordate leaf blade always has a cordate base but a cordate leaf base may not always be associated with a cordate leaf blade.
Leaf base cuneate	Wedge-shaped; referring to the base of a leaf blade of which the angle formed by the meeting of the margins is less than 90°.
Leaf base decurrent	Referring to a leaf blade base that extends down the petiole.
Leaf base lobate (lobed)	A rounded projection arising from the base of a leaf blade.
Leaf base obtuse	Blunt, referring to the the base of a leaf blade in which the two sides are straight and, when they meet, form an angle greater than 90°.
Leaf base rounded	Referring to a leaf blade base that is curved at the apex with an angle greater than 90 degrees at the point where the two sides meet.
Leaf base sagittate	The base of a leaf blade shaped like an arrowhead.
Leaf base truncate	Referring to the base of a leaf blade that terminates abruptly in a nearly straight horizontal edge.
Leaf blade	The expanded portion of a leaf, it and the petiole combined equal the leaf. Same as lamina.
Leaf flush	The expansion of new leaves.
Leaf flush	The expansion of new leaves.
Leaf gap	A region of parenchyma in the vascular tissue of a stem that is located above the level where a leaf trace diverges from the stem toward the leaf.
Leaf lamina	The expanded portion of a leaf, it and the petiole combined equal the leaf. Same as leaf blade.
Leaf margin crenate	Referring to a leaf blade margin with teeth rounded at the apex. Compare with serrate.
Leaf margin dentate	Referring to a leaf margin with sharp teeth oriented at right angles to the central axis of the leaf blade.
Leaf margin doubly serrate	Leaf blades with margins with sharp teeth oriented toward the apex with each touth in turn with a smaller tooth.
Leaf margin entire	Referring to leaf blade margins that are smooth, i.e., they have no serrations or crenations.
Leaf margin erose	Referring to leaf blade margin that is jagged, i.e., uneven but not with well-defined teeth.
Leaf margin lobed	Referring to rounded projections arising from the margins of a leaf blade that are cut less than one-half the distance to the midrib of the leaf blade, e.g., the leaves of the white oak group.
Leaf margin serrate	Leaf blades with margins with sharp teeth oriented toward the apex.
Leaf opposed	Referring to an inflorescence, infructescence, or tendril arising from the stem opposite a leaf.
Leaf scar	The scar left on a stem when a leaf falls.
Leaf sheath	Tubular, inrolled base of a leaf blade or petiole that surrounds the node and a portion of the internode; e.g., in the Cyperaceae, Poaceae, and many other monocotyledons as well as in some dicotyledons.
Leaf symmetrical	Referring to the form of a leaf with the blade equal on each side of the midrib.
Leaf symmetry	Referring to the form of a leaf in relation to the midrib, if the blade on each side of the midrib is equal the leaf is symmetrical and if the blades on each side of the midrib are not equal the leaf is asymmetrical.
Leaf venation acrodromous	Referring to a type of leaf venation in which two or more primary or strongly developed secondary veins arch upward from either the base or above it; perfect acrodromous is used when these veins converge near the apex; e.g., Strychnos (Loganiaceae); imperfect acrodromous is used when these veins do not converge at the apex. Based on Hickey, 1973. For more information about leaf venation see Ellis et al, 2009.
Leaf venation actinodromous	Referring to a type of leaf venation in which three or more primary veins diverge radially from a single point either at (basal actinodromous) or above (suprabasal actinodrmous) the point of attachment of the petiole. The primary veins can either converge at the apex (perfect actinodromous) or not converge at the apex (imperfect actinodromous). Based on Hickey, 1973. For more information on leaf venation see Ellis et al., 2009.
Leaf venation basal acrodromous	Referring to a type of leaf venation in which two or more primary or strongly developed secondary veins arch upward from the base and converge at or close to the apex.. Based on Hickey, 1973. For more information about leaf venation see Ellis et al, 2009.
Leaf venation basal actinodromous	Referring to a type of leaf venation in which three or more primary veins diverge radially from a single point at point of attachment of the petiole.
Leaf venation brochidodromous	Referring to a type of leaf venation in which the secondary veins do not terminate at the margin but join to form a series of prominent arches that form a submarginal nerve; for example, in many Myrtaceae. Based on Hickey, 1973. For more information about leaf venation see Ellis et al, 2009.
Leaf venation brochidodromous	Secondaries joined together in a series of prominent arches. Based on Hickey, 1973. For more information abouit leaf venation see Ellis et al, 2009.
Leaf venation brochidodromous festooned	Referring to a type of leaf venation in which the secondary veins do not terminate at the margin but join to form a series of prominent arches that form a submarginal nerve and, in addtion, the secondary veins possess closed loops toward their apices. Based on Hickey, 1973. For more information about leaf venation see Ellis et al, 2009.
Leaf venation camptodromous	Referring to a type of leaf venation in which the secondary veins do not terminate at the margin; in one type each secondary vein connects with the seconday vein above it (brochidodromous) and in the other type the secondary veins do not connect with the secondary vein above it (eucamtodromous). Based on Hickey, 1973. For more information about leaf venation see Ellis et al, 2009.
Leaf venation camptodromous	A type of leaf venation in which the secondary veins do not terminate at the margens
Leaf venation campylodromous	Referring to a type of leaf venation in which a series of more or less equal primary veins originate from a common point at the base, arch upward, and reunite toward the apex; e.g., species of Aristolochia (Aristolochiaceae).
Leaf venation cladodromous	Referring to a type of leaf venation in which the secondary veins branch freely before they reach the margin. Based on Hickey, 1973. For more information about leaf venation see Ellis et al, 2009.
Leaf venation eucamptodromous	Referring to a type of leaf venation in which the secondary veins do not reach the margin and do not form a series of prominent arches. Based on Hickey, 1973. For more information about leaf venation see Ellis et al, 2009.
Leaf venation eucamptodromous	Secondaries upturned and gradually diminishing apically inside the margin but not connecting to the secondary above it. Based on (Hickey, 1973. For more information about leaf venation see Ellis et al. (2009).
Leaf venation flabellate	Referring to leaf venation with several to many fine basal veins that spread out from the base like a fan and divide somewhat toward the apex. Based on Ellis et al., 2009.
Leaf venation hyphodromous	Referring to a leaf blade with all but the midvein absent or not visible because the leaf blade is too fleshy for them to be seen.
Leaf venation imperfect acrodromous	Referring to a type of leaf venation in which two or more primary or strongly developed secondary veins arch upward from or above the base and do not converge at the apex. Based on Hickey, 1973. For more information about leaf venation see Ellis et al, 2009.
Leaf venation mixed craspedodromous	Referring to a type of leaf venation in which some of the secondary veins terminate at the leaf margins and the remainder of the secondary veins do not, e.g. half of the secondary veins are craspedodromous and the other half camptodromous.
Leaf venation perfect acrodromous	Referring to a type of leaf venation in which two or more primary or strongly developed secondary veins arch upward from the base or above the base and converge near the apex. Based on Hickey, 1973. For more information about leaf venation see Ellis et al, 2009.
Leaf venation reticulodromous	Referring to a leaf venation type in which the secondary veins form a network of veins soon after departing from the midrib. Based on Hickey, 1973. For more information about leaf venation see Ellis et al, 2009.
Leaf venation simple craspedodromous	Referring to a type of leaf venation in which all of the secondary veins terminate at the leaf margins.
Leaf venation suprabasal acrodromous	Referring to a type of leaf venation in which two or more primary or strongly developed secondary veins arch upward from above the base. Based on Hickey, 1973. For more information about leaf venation see Ellis et al, 2009.
Leaf venation suprabasal actinodromous	Referring to a type of leaf venation in which three or more primary veins diverge radially from a single point above the point of attachment of the petiole.
Leaflet	A division of a compound leaf.
Leaflets alternate	Leaflets not placed along the rachis of a pinnately compound leaf directly opposite one another.
Leaflets opposite	Referring to leaflets placed along the rachis directly opposite of one another.
Leafstalk	In legumes, the main axis of the leaf from its attachment to its apex; i.e., the petiole plus the rachis.
Legume	A fruit that is derived from a single carpel, dehisces along two sutures, and is usually dry and several-seeded. Although most species of the legume family possess legumes, a number of them do not (e.g., species of Andira).
Legume family	Informally, a member of the legume family sensu lato (Fabaceae). Some species of legumes are indehiscent.
Lemma	The lower of the two bracts that enclose the floret of the Poaceae, located above the glumes. Compare with palea.

• First
• Previous
• Page / 41
• Next
• Last