Microorganisms Taxonomy and Classification Flashcards

Taxonomy and Classification

• Taxonomy is a formal system for classifying, organizing, and naming living organisms.
• Taxa refer to the various categories used in taxonomic classification.
• Classification arranges organisms into a hierarchy of categories known as taxa from general to specific.
• Identification involves documenting traits of organisms for recognition and classification within a taxonomic framework.

Naming Organisms

• The binomial system of nomenclature uses two names to identify organisms: a capitalized genus name and a lowercase species name, both italicized or underlined when handwritten.

Taxonomic Hierarchy

• The levels of classification include:
  • Domain (broadest category sharing general traits)
  • Kingdom (second division within domains)
  • Phylum (third level, often referred to as a division in some organisms)
  • Class (follows phylum)
  • Order (follows class, where organisms show increasing similarities)
  • Family (groups closely related organisms within an order)
  • Genus (second most specific level, divided into several species)
  • Species (most specific level of organization)

Evolution and Relatedness

• Hierarchies represent levels of power and rank among organisms.
• Phylogeny refers to the relatedness of groups of organisms through descent.
• Natural selection is the evolutionary process favoring traits that enhance survival.
• Two preconceptions of evolution include the origin of new species from preexisting ones and the similarity of closely related organisms due to a common ancestor.

Evolutionary Concepts

• Reductive evolution describes a regression toward lesser complexity, contrasting with the typical trend toward greater complexity.
• A clade is a group of related organisms distinguished by their descent.

Molecular Biology and Taxonomy

• Proteins and nucleic acids are key macromolecules used to study organismal differences, as their sequences can be aligned and compared for relatedness.

Woese-Fox System

• Proposed by Carl Woese, this system categorizes cell lines and major taxonomic groups into three domains: Bacteria, Archaea, and Eukarya, indicating evolutionary relationships among them.

Test your knowledge on the terminology and concepts related to the taxonomy and classification of microorganisms. This quiz covers key terms such as 'taxonomy', 'taxa', 'classification', and 'identification', aiding in your understanding of biological organization.