Classification Classification n The grouping of organisms based
Classification
Classification n The grouping of organisms based on similarities. n Allows us to study relationships between species. n Helps assign names to organisms.
How are organisms classified? n Structural similarities n Potential to mate n Geographic distribution n Chromosomes n DNA sequence n Evolutionary relationship in fossil record
7 Levels of Classification (Largest to Smallest) Kingdom n Phylum n Class n Order n Family n Genus n Species n
Taxonomy n The science of naming and classifying organisms. n Aristotle: 1 st to classify organisms. n Placed into two groups: Plants and Animals
Carlous Linnaeus n Swedish botanist who developed the naming system for classifying organisms called binomial nomenclature.
Binomial Nomenclaturesystem used universally for naming organisms. Each name consists of two words (Genus and Species) n First word capitalized n Second word lower-case n Both word written in italics n Ex: Ursus arctos- Scientific Name (Genus) (species) Common name is Grizzly Bear. n
Another Example of Naming n Acer rubrum (Red maple) n Acer = genus including all maple trees n rubrum = red
The 6 Kingdoms
Archaebacteria n Unicellular n Prokaryote- no nucleus or membrane bound organelles (have DNA, cytoplasm and ribosomes) n Autotroph or heterotroph. n Cell wall without peptidoglycan- a carbohydrate n Ex: Methanogens, Halophiles
An undersea Black Smoker!!
Eubacteria n Unicellular n Prokaryote n Autotroph or Heteroptroph n Cell wall with peptidoglycan n Ex: Streptococcus, E. Coli
This guy causes 80% of all ulcers!!
Protista n Most unicellular, some multicellular n Eukaryote n Autotroph or Heterotroph n Cell wall of cellulose, some have chloroplasts n Ex: Amoeba, Paramecium
Fungi n Most multicellular, one unicellular (yeast) n Eukaryote n Heterotroph n Cell wall made of chitin, no chloroplasts n Ex: Mushrooms, mold, yeast, morel
Plantae n Multicellular n Eukaryote n Autotroph n Cell wall made of cellulose, has chloroplasts n Ex: mosses, ferns, flowering plants
Animalia n Multicellular n Eukaryote n Heterotrophs n No cell wall, no chloroplast n Ex: sponges, worms, insects, fish, birds, amphibians, reptiles, mammals
Classification based on Evolutionary Relationships Phylogeny: the evolutionary history for a group of species. n Cladistics: classification based on common ancestry. n Scientists look at more than just physical traits when classifying organisms. n Cladistics places species in the order in which they descended from a common ancestor. n
Cladogram n Cladogram: evolutionary tree that proposes how species may be related to each other through common ancestors. n Derived Characters: traits that are shared among a group of species but not shared with others. Used to determine evolutionary relationships.
Dichotomous Key n Chart of paired statements used to identify an organism. n Classifying into two opposite parts. n For Example: 1 a. Organism has hair or fur……………. . Go to 2 1 b. Organism does not have hair or fur…. Go to 5
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