Transcript Classification

Classification
CH18 pg 421
Classification of Living Organisms
• Identified by traits
• Organize life’s diversity
– Over 1.7 million species on Earth
• Taxonomy
• Naming and classifying organisms
• Scientific Nomenclature
Scientific Nomenclature
• Carl Linnaeus
• 1750, the binomial nomenclature
• 2 word system that includes the genus and species
• Genus represents the “noun”
• Species represents the “adjective”
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Scientific name
•
No two different species have the same name
Rules for Using Scientific Names
• 2 latin or latin-like terms
• All members of the genus share the genus name
• Second term is descriptive, species
• Genus is capitalized and species lower case
• Both terms italicized or underlined
Linnaean system
• Classified all plants and animals
• Organisms are grouped based on their
similarities in their form and structure
• Eight basic levels of modern classification
Eight basic levels of modern
classification
• Domain
• Kingdom – encompasses large groups
• Phylum
• Class
• Order
• Family
• Genus – uniquely shared traits within a family
• Species – unique group of organisms united by
heredity or interbreeding
Humans Classification
• Domain Eukarya
• Kingdom Animalia
• Phylum Chordata
• Class Mammalia
• Order Primates
• Family Homidae
• Genus Homo or Homo
• Species sapiens or sapiens
Phylogenetics
(Systemics)
• Ancestral relationships between species.
• Created a “family tree” that links ancestor
and descendant across 1000s of generations
• Judging relatedness; grouping organisms by
similarities can be subjective.
Cladistics
• Analysis that infers ancestral relationship
between species (phylogenetics) through
comparison of shared characteristics
• Objective way to sort relatedness;
– Morphology
– molecular make-up
– order and time of existence
Illustrating Relationships
Phylogenetic tree
• Constructing Cladograms
– Organisms are grouped together through the
identification of shared derived characteristic.
• Derived – evolved in one group but not in the other
– All groups that arise from one point are related by
a single ancestral lineage.
• Shared characteristics between different groups of
organisms.
• Pg 429 in textbook
Kingdoms and Domains pg 433
• Carl Linnaeus had created a way to catalogue
organisms with binomial nomenclature
– Plants and Animals
– Needed more detail
• From 2 to 6 kingdoms;
– Eubacteria, Archaebacteria, Protista, Fungi,
Plantae, and Animalia
• Cell type, cell walls, body type, nutrition, and genetics
• Divided into 3 Domains; Bacteria, Archaea, Eukarya
Prokaryote or Eukaryote
• Archaea and Bacteria
• Eubacteria and Archaebacteria
– No true nucleus or organelles
– Unicellular, autotroph or heterotroph
• Eukarya
• Protista, Fungi, Plantae, Animalia
– Complex cells, true nucleus and organelles
– Unicellular or multicellular
– Heterotroph or autotroph
– With or without cell walls (cellulose or chitin)