sci

• Systematics


  The scientific study of the diversity of organisms and their evolutionary relationships
• Taxonomy


  The science of classification and it involves the naming of organisms (nomenclature)
• Classification


  The arrangement of organisms into groups based on their similarities, which reflect evolutionary relationships among lineages
• Artificial Classification System


  Based on one or a few observable characteristics (color, how they move, habitat or their size)
• Natural Classification System


  Based on many features, internal and external (anatomy, biochemical, physiological, morphology, embryology and cytology)
• Phenetic classification


  Based on similarities in appearance, a quantitative approach (the more similarities between organisms, the more they are in the same group), computer programs are used to analyze data and group organisms according to the number of shared characteristics
• Phylogenic classification


  Based on shared characteristics which reflects evolutionary relationships or phylogeny (evolutionary classification), biologist compare not only the physical similarities but also the development, behavioral, and molecular traits
• Homologous structures


  • Shared ancestral characteristics or plesiomorphic characteristics (traits that were present in an ancestral species and remain present in the organisms)
  • Shared derived characteristics or synapomorphic characteristics (traits shared by a group of taxa due to their inheritance from a common ancestor)
• Cladogram


  Used to trace the process of evolution in a group of organisms based on shared derived characteristics, help scientists understand how one lineage branched from another in the course of evolution, each branch point (node) represents the most recent common ancestor
• Taxon


  A group that contains organisms that share some basic features that indicate they share a common ancestry
• The seven main taxa

  • Kingdom
  • Phylum
  • Class
  • Order
  • Family
  • Genus
  • Species
• Binomial nomenclature


  The system of naming, a standard two-part system for naming things, developed by Carolus Linnaeus in which species is given a name consisting of two words
• Generic name


  The name of the genus (written with an uppercase letter)
• Specific epithet


  The name of the species (written with a lowercase letter)
• Three Domains


  • Domain Eukarya
  • Domain Eubacteria
  • Domain Archaea
• domain


  top level classification that categorize life in the most general way
• kingdom 


  largest and most inclusive grouping
• phylum


  organisms organized on a similar plan
• class 


  grouping of orglders within a phylum
• order 


  group of related families
• family


  group of related genera
• genus


  group of similar and losely related species
• species


  group of ogranisms capable of interbreeding to produce fertile offspring