|
Grex (actor)
Grex or GREX may refer to: * Grex (biology), a multicellular aggregate of amoeba of the phyla Acrasiomycota or Dictyosteliomycota * Grex (horticulture), (pl. greges) a kind of group used in horticultural nomenclature applied to the progeny of an artificial cross from specified parents * Formerly used to mean species aggregate In biology, a species complex is a group of closely related organisms that are so similar in appearance and other features that the boundaries between them are often unclear. The taxa in the complex may be able to hybridize readily with each oth ... * Georgetown Rail Equipment Company, a provider of railway maintenance equipment and related services based in Georgetown, Texas {{disambiguation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Grex (biology)
A grex, (also called a pseudoplasmodium, or slug) starts as a crowd of single-celled amoebae of the groups Acrasiomycota or Dictyosteliida; ''grex'' is the Latin word for ''flock''. The cells flock together, forming a mass that behaves as an organised, slug-like unit. Before they get stimulated to crowd together to form a grex, the amoebae simply wander as independent cells grazing on bacteria and other suitable food items. They continue in that way of life as long as conditions are favourable. When the amoebae are stressed, typically by a shortage of food, they form a grex. According to species and circumstances, details of the shape of the grex and how it may form will vary but typically the stressed amoebae first produce pheromones that stimulate the flock to vertically assemble in a column. When the column of aggregated cells becomes too high and narrow to stay upright, it topples and becomes a slug-shaped mass: the grex. The grex is mobile; in its form as a slug-like unit i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Grex (horticulture)
The term ''grex'' (plural ''greges'' or ''grexes''; abbreviation gx), derived from the Latin language, Latin noun , , meaning 'flock', has been expanded in botanical nomenclature to describe hybrids of orchids, based solely on their parentage. Grex names are one of the three categories of plant names governed by the International Code of Nomenclature for Cultivated Plants; within a grex the ''cultivar group'' category can be used to refer to plants by their shared characteristics (rather than by their parentage), and individual orchid plants can be selected (and propagated) and named as cultivars. Botanical nomenclature of hybrids The horticultural nomenclature of grexes exists within the framework of the botanical nomenclature of hybrid plants. Interspecific hybrids occur in nature, and are treated under the International Code of Nomenclature for algae, fungi, and plants as nothospecies, ('notho' indicating hybrid). They can optionally be given Linnean Binomial nomenclature, bin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Species Aggregate
In biology, a species complex is a group of closely related organisms that are so similar in appearance and other features that the boundaries between them are often unclear. The taxa in the complex may be able to hybridize readily with each other, further blurring any distinctions. Terms that are sometimes used synonymously but have more precise meanings are cryptic species for two or more species hidden under one species name, sibling species for two (or more) species that are each other's closest relative, and species flock for a group of closely related species that live in the same habitat. As informal taxonomic ranks, species group, species aggregate, macrospecies, and superspecies are also in use. Two or more taxa that were once considered conspecific (of the same species) may later be subdivided into infraspecific taxa (taxa within a species, such as bacterial strains or plant varieties), that is complex but it is not a species complex. A species complex is in most cas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
