Order
The taxonomic classification level between class and family. For example, within the class Mammalia, there are several orders, including the meat-eaters, who make up the order Carnivora; and the insect-eaters, grouped together in the order Insectivora. The orders in turn are divided into families; the order Carnivora includes the families Felidae (the cats), Canidae (the dogs), and Ursidae (the bears), among others. See also taxon.
Ordered spores
A linear sequence of four haploid meiotic spores (or pairs of spores produced by a post-meiotic division) within a fungi ascus; this arrangement allows identification of chromatids participating in crossover events.
Organelle
Any of a number of distinct small structures found in the cytoplasm (and therefore outside the nucleus) of eukaryotic cells (e.g., mitochondrion and chloroplast).
|