CLASSIFICATION What is does the word classify mean? Classify -to group things according to similar/different features (structures) that they share Biologist use a classification system to name and group organisms in a logical manner. Taxonomy : It is the science of classifying organisms and assigning them universally accepted names.

Binomial Nomenclature Binomial nomenclature is a two-words naming system developed by Carolus Linnaeus. In this system, a species is assigned a two-part scientific name. – Always written in ITALICS – First word Capitalized – Second word lower case – First word is the genus – Second word is the species – Always in Latin – Example: Homo sapien

7 Levels of Classification K ingdom broadest level P hylum C lass O rder F amily G enus S pecies most specific Each level is called a taxon

An easy way to remember K ing P hillip C ame O ver F or G ood S oup!

Example 1. Grizzly Bear Ursus arctos Genus = Ursus Species = arctos 2. Polar Bear Ursus maritimus Genus: Ursus Species: maritimus

Phylogeny Study of evolutionary relationships among organisms

Cladogram A diagram that shows the evolutionary relationships among a group of organisms

Evolutionary Classification Strategy of grouping organisms together based on their evolutionary history

Derived characters Derived characters: These are characteristics that appear in recent parts of a lineage but not in its older members. Similarities in DNA can be used to help determine classification and evolutionary relationships

Molecular Clock A model that uses DNA comparisons to estimate the length of time that two species have been evolving independently.

Three Domains of life

The six kingdoms are:

Archaebacteria  “ancient bacteria”  Unicellular  Some species are heterotrophs (can’t make their own food) while some are autotrophs (can make own food).  They are prokaryotes, meaning they do not have a nucleus,  They live in extreme environments (volcano hot spring)  Survive in the absence of oxygen.  Cell walls lack peptidoglycan.  Examples: Methanogens, halophiles

 Like archaebacteria, they are unicellular and are prokaryotes.  Some species are heterotrophs, while others are autotrophs.  There are both helpful and harmful organisms in this kingdom. Have thick, rigid cell wall made up of petidoglycan  Some need oxygen and some don’t  Examples: Gonococcus, streptococcus, E.coli Eubacteria

Checkpoint 1. How are eubacteria and archaebacteria similar? 2. How are they different?

Protists  “ Odds and ends” Mostly unicellular and some multicellular.  They are eukaryotes they have a true nucleus.  Some are autotrophs and some heterotrophs.  Some have cellulose cell wall & chloroplast  Examples : Amoeba, paramecium, slime mould giant kelp

Fungi  Multicellular organisms  Eukaryotes  Heterotrophs  Most live dead or decaying matter.  Have cell walls made up of chitin  Example: Mushroom, yeast molds

Plants  Autotrophs  Eukaryotes  Produce oxygen, which many organisms require.  Multicellular  Have cellulose cell wall & Chloroplast  Examples: Mosses, flowering plants Ferns

Animals  Multicellular  Eukaryotes  Heterotrophs  Live in diverse environments Have no cell wall or chloroplast Examples: sponges worms insects fishes mammals

The Three Domains of Life 1.Bacteria : Eubacteria 2.Archaea : Archaebacteria 3. Eukarya : Protist Fungi Plantae Animalia DOMAIN Kingdoms2-Examples each.