Module 1 Classification of Living Things PDF

Mod 1. Classification of Living Things Paraphyletic - group consisting of a common Biologists - classify living things by ancestor and some, but not all, of its descendants. arranging organisms into division...

Mod 1. Classification of Living Things Paraphyletic - group consisting of a common Biologists - classify living things by ancestor and some, but not all, of its descendants. arranging organisms into divisions and Polyphyletic - derived from more than one subdivisions. common evolutionary ancestor and therefore not suitable for placing in the same taxon. Taxonomy - process of arranging organisms into groups based on similarities. Linnaean system is based on similarities in obvious physical traits. It consists of a hierarchy of taxa, from the kingdom to the species. Recent system: all living organisms are grouped into main divisions called KINGDOMS Cladistics - classification of organisms based on - Kingdom Plantae & Kingdom Animalia recency of common ancestry rather than degree of structural similarity. Info: Biologists use scientific names to precisely identify organisms Cladists - emphasize phylogeny by focusing on when evolutionary lineages (lines of descent) - Each organism has only one scientific name divide into two branches. (avoids confusion of many common names) Cladists develop cladograms. In the Binomial Nomenclature Cladograms - a diagram that illustrates Species - the basic unit of classification evolutionary relationships based on the principles The scientific name of each species has two parts: of cladistics. generic name (genus) and specific epithet. Domain Bacteria – a domain of metabolically Subspecies - a group within a species that has diverse, unicellular, prokaryotic organisms. become somewhat physically and genetically different from the rest of the group. Domain Archaea - a domain of unicellular, prokaryotic organisms adapted to extreme Species - is a group of living things with very conditions (such as very hot or very salty similar traits that interbreed. environments). Systematics - a scientific study of the diversity of Info: Like bacteria, archaea do not have interior organisms and their natural (evolutionary) membranes, but both have a cell wall and use flagella relationships. to swim. Systematist - seeks to reconstruct phylogeny. Phylogeny - evolutionary history of a species or Info: Archaea differ in the fact that their cell wall does other taxonomic group not contain peptidoglycan and cell membranes use Monophyletic - group consisting of organisms that ether-linked lipids as opposed to ester-linked lipids in evolved from a common ancestor. bacteria. Domain Eukarya - Includes all eukaryotic organisms (protists, plants, fungi, and animals)  In biology, a kingdom is a taxonomic rank that is composed of smaller groups called phyla. Phyla - divisions, in plants. NOTE: Historically, the kingdom is the highest taxonomic rank, or the most general taxon used in classifying organisms. Phylum - the primary subdivision of a taxonomic kingdom. - grouping all classes of organisms that have the same body plan. Class - a taxonomic group comprised of organisms that share a common attribute. - It is further divided into one or more orders. Order - a taxonomic rank used in classifying organisms, generally below the class. - And comprised of families sharing a set of similar nature or character - suffix ends in – ales Family - more precise than orders but less precise than genera. - Organisms belonging to the same family would have evolved from the same ancestors and share relatively common characteristics. Genus - a taxonomic category ranking used in biological classification that is below family and above species. Species - exhibiting similar characteristics comprise a genus. INFO: : term genus was borrowed from Latin. It means “birth”, descent, “origin”, “sort”, or “type”. The plural form is genera. Thus, the meaning of genera pertains to more than one genus as most taxonomic families are comprised of several genera. Domain - the highest taxonomic rank in the hierarchical biological classification system, above INFO: In binomial nomenclature, the genus is used as the kingdom level. the first word of a scientific name in which the first letter is capitalized. NOTE: There are three domains of life, the Archaea, the Bacteria, and the Eukarya. Together with the specific epithet, they are italicized or appended with quotes e.g. Homo sapiens or “Homo sapiens” For example, the ambrosia beetle and the platypus THE NAMING SYSTEM have been given the generic name Platypus. - In binomial nomenclature, the genus is used as - the first word of a scientific name. The genus name is always capitalized and italicized. For example, the binomial name of the corn is Zea mays. The first part, Zea, is the genus name whereas the second part, mays, is the specific epithet. - A taxonomist assigns a scientific name for a particular species. For a genus to be descriptively useful, it must have monophyly, reasonable compactness, and distinctness. Willi Hennig, a German biologist - defined monophyly as groups based on shared derived characteristics As for reasonable compactness, it means that the genus needs not to be expanded unnecessarily. The genus name must also show distinctness concerning evolutionary relevant criteria such as ecology, morphology, or biogeography. NOTE: The binomial name is different from the common or vernacular name. Vernacular name - non- standardized and varies by location. binomial name – a standardized and usage is globally accepted. homonym in biological classification is a name that is associated with two different taxa.