Term
|
Definition
| two-part latinized name of a species, consisting of the genus and specific epithet |
|
|
Term
|
Definition
| taxonomic category above the species level, designated by the first word of a species two-part scientific name |
|
|
Term
|
Definition
| taxnomic category above class |
|
|
Term
|
Definition
| taxonomic category, the second broadest after domain |
|
|
Term
|
Definition
| branching diagram that represents a hypothesis about the evolutionary history of a group of organisms |
|
|
Term
|
Definition
| system of classifcation of organisms based on evolutionary relationships: only group that include common ancestor and all of its descendants are named |
|
|
Term
|
Definition
| representation of a phylogenetic tree of the divergence of two or more taxa from a common ancestor |
|
|
Term
|
Definition
| groups of organisms that share an immediate common ancestor and hence are each other's closest relatives |
|
|
Term
|
Definition
| describing a phylogenetic tree that contains a branch point representing the last common ancestor of all taxa in the tree |
|
|
Term
|
Definition
| in a phylogenetic tree, a branch point from which more than two descendant taxa emerge; indicates that the evolutionary relationships among the descendant taxa are not yet clear |
|
|
Term
|
Definition
| similarity between two species that is due to convergent evolution rather than to descent from a common ancestor with the same trait |
|
|
Term
|
Definition
| similar structure or molecular sequence that has evolved independently in two species |
|
|
Term
|
Definition
| scientific discipline that uses nucleic acids or other molecules in different species to infer evolutionary relationships |
|
|
Term
|
Definition
| pertaining to a group of taxa that consists of a common ancestor and all its descendants; equivalent to a clade |
|
|
Term
|
Definition
| pertaining to a group of taxa that consists of a common ancestor and some, but not all of its descendants |
|
|
Term
|
Definition
| pertaining to a group of taxa derived from two or more different ancestors |
|
|
Term
|
Definition
| principle that states that when considering multiple explanations for an observation, one should first investigate the simplest explanation that is consistent with the facts |
|
|
Term
|
Definition
| (systematics) principle that states that when considering multiple phylogenetic hypotheses, one should take inot account he hypothesis that reflects the mostly likely sequence of evolution events, given certain rules about how DNA changes over time |
|
|
Term
|
Definition
| approach in which features shared by two groups of organism are predict (by parsimony) to be present in their common ancestor and all o fits descendants |
|
|
Term
|
Definition
| homologous genes that are found in different species because of speciation |
|
|
Term
|
Definition
| homologous genes that are found in the same genome as a result of gene duplication |
|
|
Term
|
Definition
| hypothesis that much evolutionary change in genes and proteins has no effect on fitness and therefore is not influenced by Darwinian natural selection |
|
|
Term
|
Definition
| transfer of genes from one genome to another through mechanisms such as transposable elements, plasmid exchange, viral activity, and perhaps fusions of different organisms |
|
|
Term
|
Definition
| type of polymer in bacterial cell walls consisting of modified sugars cross-linked by short polypeptides |
|
|
Term
|
Definition
| staining a method that distinguishes between two different kinds of bacterial cell walls |
|
|
Term
|
Definition
| describing the group of bacteria that have a cell wall that is structurally less complex and contains more peptioglycan than the cell wall of gram-negative; usually less toxic |
|
|
Term
|
Definition
| describing the group of bacteria that have a cell wall that is structurally more complex and contains less peptidoglycan than the cell wall of gram-positive bacteria; often more toxic |
|
|
Term
|
Definition
| short, hairlike appendage of a prokaryotic cell that helps it adhere to the substrate or to other cells; also known as an attachment pilus |
|
|
Term
|
Definition
| in bacteria, a structure that links one cell to another at the start of conjugation; also known as a conjugation pilus |
|
|
Term
|
Definition
| oriented movement toward or away from a stimulus |
|
|
Term
|
Definition
| region in a prokaryotic cell consisting of a concentrated mass of DNA |
|
|
Term
|
Definition
| small, circular, double-stranded DNA molecule that carries accessory genes separate from those of a bacterial chromosome; also found in some eukaryotes (yeast) |
|
|
Term
|
Definition
| change in genotype and phenotype due to the assimilation of external DNA by a cell |
|
|
Term
|
Definition
| type of horizontal gene transfer in which phages (viruses) carry bacterial DNA from one host cell to another |
|
|
Term
|
Definition
| in prokaryotes, the direct tranfer of DNA between two cells (of same or different species) that are temporarily joined; in ciliates, secual process in which two cells exchange haploid micronuclei |
|
|
Term
|
Definition
| plasmid form of the F factor |
|
|
Term
|
Definition
| in bacteria, DNA segment that confers the ability to form pili for conjugation and associated function required for the transfer of DNA from donor to recipient; may exist as a plasmid or integrated into the bacterial chromosome |
|
|
Term
|
Definition
| bacterial plasmid carrying genes that confer resistance to certain antibiotics |
|
|
Term
|
Definition
| organism that requires oxygen for cellular respiration and cannot live without it |
|
|
Term
|
Definition
| organism that only carries our fermentation or anaerobic respiration; cannot use oxygen and might be poisoned by it |
|
|
Term
|
Definition
| specialized cell that engages in nitrogen fixation in some filamentous cyanobacteria; formerly called heterocyst |
|
|
Term
|
Definition
| surface-coating colony of one or more species of prokaryotes that engage in metabolic cooperation |
|
|
Term
|
Definition
| organism that lives in a highly saline environment, such as the Great Salt Lake or the Dead Sea |
|
|
Term
|
Definition
| organism that thrives in hot environemnts (60-80+ degrees Celsius) |
|
|
Term
|
Definition
| any of the saprobic fungi and prokaryotes that absorb nutrients from nonliving organic material, (such as corpses, fallen plant material, an the wates of living organism) and convert them to inorganic forms; a detritivore |
|
|
Term
|
Definition
| smaller participant in a symbionotic relationship, living in or on the host |
|
|
Term
|
Definition
| larger participant in a symbiotic relationship, serving as home an food source for the smaller symbiont |
|
|
Term
|
Definition
| symbiotic relationship in which both participants benefit |
|
|
Term
|
Definition
| symbiotic relationship in which one organism benefits but the other is neither helped nor harmed |
|
|
Term
|
Definition
| symbiotic relationship in which one organism, the parasite, benefits and the expense of another, the host, by living either within or on the host |
|
|
Term
|
Definition
| organism that feeds on the cell contents, tissues, or body fluids of another species (the host) while in or one the host organism; harm but do not kill their host |
|
|
Term
|
Definition
| organism or virus that causes disease |
|
|
Term
|
Definition
| toxic protin that is screted by a prokaryote or other pathogen and that produces specific symptoms, even if the pathogen is no longer present |
|
|
Term
|
Definition
| toxic component of the outer membrane of certain gram-negative bacteria that is released only when the bacteria die |
|
|
Term
|
Definition
| use of living organism to detoxify and restore polluted and degraded ecosystems |
|
|
