A system of nomenclature in biological taxonomy whereby each type of plant or animal is given a two-word name, with the first name identifying the genus and the second the species. The genus name is always capitalized and abbreviated after the first use, and the species name is lower-cased. Both are always shown in italics—thus, Homo sapiens and, later in the same document, H. sapiens.
The third most general of the obligatory taxonomic classification ranks, after phylum but before order.
Deoxyribonucleic acid, a molecule in all cells, and many viruses, containing genetic codes for inheritance.
Anyplant, animal, or microorganism that is at risk of becoming extinct or at least of disappearing from a particular local habitat.
Species that exist in only one geographic region.
A cell that has a nucleus as well as organelles (sections of the cell that perform specific functions) bound bymembranes.
Species that have been introduced to a region or continent, usually but not always through humanactivity. See also introduced species and invasive species.
A condition in which all members of a taxon have ceased to exist.
The third most specific of the seven obligatory ranks in taxonomy, after order but before genus.
A unit of information about a particular heritable (capable of being inherited) trait that is passed from parent to offspring, stored in DNA molecules called chromosomes.
The sum of all the genesshared by a population, such as that of aspecies.
The second most specific of the obligatory ranks in taxonomy, after family but before species.
The product of sexual union between members of two species or other smaller and less genetically separate groups, such as two races. In the case of species hybrids, the process of hybridization involves genetic abnormalities that>lead in most cases to sterility.
A species that has been spread to a new environment or habitat, whether deliberately or accidentally, as a result of human activity. Introduced species, like invasive species, are considered exotic species.
An exotic species that threatens some aspect of the habit at to which it has been introduced.
The highest or most general ranking in the obligatory taxonomic system. In the system used in this book there are five kingdoms: Monera, Protista, Fungi, Plantae, and Animalia.
Structure or form, or the study thereof.
The process whereby some organisms thrive and others perish, depending on their degree of adaptation to a particular environment.
The act or process of naming or a system of names—particularly one used in a specific science or discipline. See also binomial nomenclature.
The middle of the seven obligatory ranks in taxonomy, more specific than class but more general than family.
The second most general of the obligatory taxonomic classificationranks, after kingdom and before class.
A cell without a nucleus.
Ribonucleic acid, the molecule translated from DNA in the cell nucleus, the control center of the cell, that directs protein synthesis in the cytoplasm, or the space between cells.
The divergence of evolutionary lineages and creation of new species.
The most specific of the seven obligatory ranks in taxonomy. Species often are defined as a population of individual organisms capable of mating with one another and producing fertile offspring in a natural setting. Also, members of the same species share a gene pool.
A taxonomic group or entity.
The area of the biological sciences devoted to the identification, nomenclature, and classification of organisms according to apparent common characteristics.
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