anisostemonous |
|
architecture |
flower, androecium |
Having stamens unequal in size and/or shape. |
annual 1 |
|
duration |
plant, stem |
Normally living one year or less; growing, reproducing, and dying within one cycle of seasons. |
annual 2 |
|
nominative |
plant |
Of annual duration. |
annular |
= ring-shaped |
solid shape |
|
More or less evenly tubular in a closed circle; like a ring or doughnut. |
annulus 1 pl. annuli |
|
STRUCTURE |
|
A small ring-like protrusion from the strobilar stalk near its base and below the lowermost sporangiophores, sometimes bearing small sporangia; esp. in Equisetum. |
annulus 2 pl. annuli |
|
STRUCTURE |
|
A row of protruding specialized sporangial wall cells that extends upward from the base of the sporangium and over its apex, thus forming an incomplete circumferential ring; esp. in Polypodiophyta. The inner and radial walls of the annular cells are markedly thickened and the structure functions as a spore-releasing and -disseminating mechanism as a result of differential stresses developed within the mature sporangial wall upon desiccation. |
anomocytic |
= ranunculaceous |
architecture |
stomate |
Lacking subsidiary cells. |
anthela pl. anthelae |
|
nominative |
inflorescence |
A cyme with the main axis markedly shorter than the lateral axes, appearing generally paniculate when compound; esp. in Juncaceae. |
anthelate |
|
architecture |
inflorescence |
Comprising one or more anthelae; esp. in Juncaceae. |
anther |
|
STRUCTURE |
|
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). |
anther-bearing |
= antheriferous |
architecture |
floral structure |
Bearing anthers. |
antheridium pl. antheridia |
|
STRUCTURE |
|
A male gametangium; a multicellular fertile organ of a mature gametophyte within which male gametes (antherozoids, spermatozoids) are produced and from which they are discharged, in some taxa forcibly, through a pore. Technically present but highly reduced and of no descriptive significance in Magnoliophyta and part of Pinophyta. |
antheriferous |
= anther-bearing |
architecture |
floral structure |
Bearing anthers. |
antherozoid |
= spermatozoid; < sperm |
STRUCTURE |
|
A motile male gamete, produced within an antheridium. |
anthocarp |
= accessory fruit; > diclesium |
nominative |
fruit |
Simple or compound and including some tissue of non-ovarian origin (accessory tissue). |
anticlinal |
|
orientation |
|
Perpendicular to some given plane of reference; applied especially to the plane of cell division when it is oriented at right angles to the generalized plane of the structural surface. |
antipetalous |
|
insertion |
equivalent floral structures |
Each inserted directly above or below a petal. In place of this term, the phrase "opposite the petals" is often used, but that contradicts the sense of opposite as otherwise employed (arrangement of lateral structures along an axis) and should be avoided. |
antipetalous |
|
position |
equivalent floral structures |
Each inserted directly above or below a petal. In place of this term, the phrase "opposite the petals" is often used, but that contradicts the sense of opposite as otherwise employed (arrangement of lateral structures along an axis) and should be avoided. |
antisepalous |
|
insertion |
equivalent floral structures |
Each inserted directly above or below a sepal. In place of this term, the phrase "opposite the sepals" is often used, but that contradicts the sense of opposite as otherwise employed (arrangement of lateral structures along an axis) and should be avoided. |
antisepalous |
|
position |
equivalent floral structures |
Each inserted directly above or below a sepal. In place of this term, the phrase "opposite the sepals" is often used, but that contradicts the sense of opposite as otherwise employed (arrangement of lateral structures along an axis) and should be avoided. |
antrorse |
|
orientation |
|
Directed forward or upward, toward the distal end of the context of reference, parallel or at an acute angle to the bearing structure. |
apetalous |
|
architecture |
flower, perianth |
Lacking petals. |
apex pl. apices |
|
CHARACTER |
|
Configuration of the uppermost, distal, or terminal portion of a structure, its extent determined somewhat subjectively in relation to the shape of the structure as a whole. The concept of apex varies from one descriptive context to another, since the apex is not a clearly delimited, morphologically distinct entity. The terms for describing apical condition are not strictly coordinate logically — some are more inclusive than others, some describe conditions involving what can be regarded as appendages, and some refer to the apex in a developmental as well as a strictly topological sense — and precise characterization may require using more than one descriptor. The semantic antecedent of some descriptors is "apex," whereas the antecedent of others is the structure as a whole (e.g., leaf ). |
aphyllous |
= leafless |
architecture |
plant, axis |
Not bearing leaves. |
apical |
< distal |
insertion |
|
At or very near the developmental end or tip (apex) of a structure. |