Glossary - The Pollination Biology of North American Orchids: North of Florida and Mexico - page 185

Glossary
Abdomen In insects, the posterior segment of the body.
Achlorophyllous Lacking chlorophyll and therefore non-photosynthetic and depen-
dent on fungi for nourishment.
Acropetal A process that begins at the base and proceeds toward the apex.
Acuminate Tapering gradually into a slender, extended point.
Acute Margins (e.g., of leaves or flower parts) meeting at an angle of less than 90°,
the tip distinct but not extended.
Adaptation The modification of an organism, a character, or a habit to fit the
environment.
Adaxial The side of an organ (leaf, bract, or floral part) directed toward the main
axis, normally the inner or upper surface.
Agamospermy A form of apomixes in which seeds and embryos are produced
asexually from a diploid cell with no fertilization; cf. pseudogamy.
Allogamy Cross-fertilization or outbreeding.
Allozyme In our sense, the variants of an enzyme genetically coded by different
alleles of a single gene as distinguished through electrophoretic analysis of
enzyme phenotypes.
Aneuploidy (Aneuploid) The occurrence of one or more extra or missing chro-
mosomes.
Angiosperms A class of vascular plants that characteristically produce seeds
enclosed in an ovary, flowering plants.
Annual A plant that germinates from a seed, grows, flowers, produces seeds, and
then dies within a single year; cf. perennial.
Anther The part of the stamen or male organ that produces pollen.
Anther cap A structure covering the pollinia in orchids.
Anthesis Specifically the opening of the stamens, but more generally, the stage
when the flower bud opens and the period during which the flower is open and
functional.
Apex (pl. apices, adj. apical) The tip or terminal point of a perianth part, leaf,
bract, or stem.