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