Classification Flashcards
Define classification
Arrangement of organism into groups of various sizes on the basis of shared features
Describe the two types of classification
Taxonomy= focuses on physical similarities between different species for ease of naming + identification
Phylogeny = classifies organism by their evolutionary relationships so every group shares a common ancestor
Who developed the firstborn formal taxonomy system?
Carl Linnaeus (Linnaeun Taxonomy)
What is the binomial naming system?
Genus & species (written in italics, underlined in exams)
Name the order of classification in the Linnaeun system
Domain, Kingdom, Phylum, Class, Order, Family, Genus, Species (Dear King Philip came over for good sex)
Describe the two types of definitions for species
Biological species concept - defines species as individuals which can reproduce to form fertile offspring
Phylogenetic species concept - defines species by its evolutionary lineage; when two lines diverge significantly they are called a different species
Give problems for each type of definition for species
- Biological = some organisms are extinct or reproduce asexually
- Phylogenetic = difficult to decide what constitutes a sufficient divergence
Who proposed the three domain system?
Carl Woese
What is the 3-domain system based on?
Based on RNA + protein structure
Describe the three domains in the 3 domain system
Eukaryota - organisms possessing complex organelles
Bacteria - true bacteria
Archaea - primitive bacteria
What is molecular phylogeny?
Looking at DNA, RNA + proteins to find evolutionary relationships; more similar amino acid sequence = closer related
Describe role of scientific community in classification
Findings of molecular phylogeny studies are published in scientific journals and presented at conferences
They are then analysed by peer review, and experiments are repeated to confirm results
If the scientific community agrees with the results, the organism will be officially classified into the particular taxonomic group
