PBT M7

• CLASSIFICATION

  • is the systematic arrangement of organisms in groups or categories according to an established specific criterion.
• SYSTEMATICS

  • is the study of biological diversity of organisms and their natural evolutionary relationship to other organisms and their environment.
• TAXONOMY

  • is the science of naming, describing, and classifying organisms including plants, animals, and even microorganisms.
  • a component of systematics that focuses more on the theory and practice of classification.
• Taxonomy and systematics

  • are not clearly separable but are frequently used by biologists interchangeably.
• PHYLOGENY

  • is the study of evolutionary history and relationship of organisms that descend from one or more ancestry
• PHYLOGENY

  Monophyletic groups

  • consists of organisms that evolved from one common ancestry.

  Polyphyletic groups

  • groups of organisms that has several evolutionary lines without common ancestry

  Paraphyletic groups

  • consists of organisms that includes a common ancestor, but not all its descendants
• CLADISTICS

  • classification of an organism based on recency of common ancestry rather than the degree of structural similarity.
  • The general goal is to reconstruct phylogenies using an analysis of evolutionary changes in specific.
• Steps in making a Cladogram

  1. Select the groups
  2. Select the homologous character to be analyzed
  3. Organize the character states into their correct evolutionary orders
• BINOMIAL NOMENCLATURE

  • a system for giving each organism a two-word scientific name.
• BINOMIAL NOMENCLATURE

  Species

  • is the basic unit of classification

  Sub-species

  • or interbreed are geographically distinct population that evolved by Natural Selection.

  Cultivar

  • are cultivated varieties of plants. These species are not equivalent to sub-species.
• Specific Epithet

  • in a binomial nomenclature is the second part uncapitalized part of the scientific name of an organism that follows the genus and often describes a particularity of an organism.
• Dichotomous Key

  • allows taxonomist to determine the identity of organisms based on keys that consists a series of choices that lead to correct identity.
• Pioneers of Plant Classification

  • Theophrastus
  • Carolus Linnaeus
• Theophrastus

  • classified plants into herbs, shrubs, and trees.
  • His De Materia Medica described 600 species of medicinal plants and was widely used a medical reference for about 1500 years until the end of the Middle Ages.
• Carolus Linnaeus

  • wrote Species Plantarum, which contains description of plants that were known in his time.
  • He observed 7300 species of plants and provided each plant with a binomial name.