Classification/Taxonomy Chapter 17

Why Classify? To study the diversity of life, biologists use a classification system to name organisms & group them in a logical manner.

In other words, naming things. Taxonomy Defined: Discipline of classifying organisms and assigning each organism a universally accepted name. In other words, naming things.

Why common names don’t work Common names vary among languages. Example: United Kingdom – Buzzard refers to a hawk United States – Buzzard refers to a vulture Red-tailed Hawk Honey Buzzard Turkey Vulture

Another Example: Dolphin Dolphin Tursipos truncatus Mahi mahi

Carolus Linnaeus (1707 – 1778) Created the system of naming we use today. In taxonomy, a group or level of organization is called a taxonomic category or taxon.

Binomial Nomenclature “Bi” means 2 “nomial” means naming Nomenclature means “the system of” Defined: In binomial nomenclature, each species is assigned a two-part scientific name. (Genus & species)

Example of Binomial Nomenclature Polar Bear is Ursus maritimus Ursus: genus Ursus contains 5 other kinds of bears maritimus: species The Latin word, maritimus, refers to the sea. Polar bears often live on pack ice that floats in the sea.

Definitions to know Genus: is a group of closely related species Species: Group of similar organisms that can breed and produce fertile offspring

Family: Group of genera that share many characteristics Order: Group of similar families Class: Group of similar orders Phylum: Group of closely related classes Kingdom: Largest taxonomic group, consisting of closely related phyla.

What do these mean?...lets see Here We Go… Polar Bear Species: maritimus Genus: Ursus Family: Ursidae Order: Carnivora Class: Mammalia Phylum: Chordata Kingdom: Animilia What do these mean?...lets see

What they mean Species: maritimus (lives in marine environment) Genus: Ursus (kind of bear) Family: Ursidae (larger category of bears) Order: Carnivora (meat-eating animals) Class: Mammalia (warm-blooded, hair, & milk) Phylum: Chordata (vertebrates) Kingdom: Animilia (there are 6 kingdoms)

How to remember: Da King Phillip Came Over For Green Salad Domain Kingdom Phylum Class Order Family Genus Species

Phylum Chordata Class Mammalia Order Carnivora Family Ursidae Genus Ursus Species maritimus

Taxonomy Video

The Three-Domain System There are 3 Domains: Domain Bacteria Domain Archaea Domain Eukarya There are 6 Kingdoms: 1. Eubacteria 2. Archaebacteria 3. Protista 4. Fungi 5. Plantae 6. Animalia

The Three-Domain System There are 3 Domains: Domain Bacteria Kingdom Eubacteria Unicellular/Prokaryotes Cell walls have Peptidoglycan Domain Archaea Kingdom Archaebacteria Cell walls withOUT Peptidoglycan Domain Eukarya Kingdoms Protista, Fungi, Plantae, Animalia

Kingdom Archaebacteria Unicellular Prokaryote Cell walls withOUT Peptidoglycan Extremophiles – Love extreme environments like volcanoes, hydrothermal vents, and hot springs Archaea Hydrothermal Vent Hot Spring Volcaone

Kingdom Eubacteria Unicellular Prokaryote Cell walls with Peptidoglycan All other bacteria you encounter everyday E. coli Staphlycoccus Streptococcus

Kingdom Protista Unicellular or Multicellular Live in colonies Video Clip: Amoeba Unicellular or Multicellular Live in colonies Amoeba Euglena Paramecium

3 Categories of Protista Plant-like Example: Algae Perform photosynthesis (autotrophs) Animal-like Example: Amoeba Can cause disease (malaria, sleeping sickness) Fungus-like Example: Slime molds

Plant-like Protists Algae Euglena Live in shallow water Photosynthetic (autotrophic) Can also be heterotrophic when light not available Absorb nutrients Ingest other organisms

Animal-like Protists Also called Protozoans 4 Types Ciliates (Example: Paramecium) Sarcodina (Example: Amoeba) Zooflagellates Sporozoans

Slime Mold

Kingdom Fungi Unicellular or Multicellular Cell walls made of Chitin Heterotrophs….they eat! Yeast Mushrooms

Kingdom Fungi Hyphae Thread-like structures which form all parts of the fungus Main function is to help fungus obtain food – provide large surface area for absorption of nutrients

Kingdom Plantae Multicellular Cell walls made of Cellulose Autotrophs….make their own food Trees & Grass Moss Venus Fly Trap

Kingdom Animalia Multicellular NO cell walls Heterotrophs….they eat Worms Insects Jellyfish Giraffes

6 Kingdoms Eubacteria Archaebacteria Protista Fungi Plantae Animalia Prokaryote Prokaryote Eukaryote Eukaryote Eukaryote Eukaryote Autotroph or heterotroph Autotroph or heterotroph Autotroph/ heterotroph Heterotroph Autotroph Heterotroph Most common bacteria Cell wall w/ Peptidoglycan Includes Algae Don’t belong in other euk No cell wall No chloroplasts Multicellular “Ancient Bacteria” Cell walls w/cellulose & Chloroplasts Release enzymes to digest food Live in very hot places E. ecoli Pyrococcus furiosus Paramecium H. coccinea Fern frod Homo sapiens

Write Scientific Names Correctly The scientific name is always the Genus and species taxa of the organism Genus capitalized Species lower cased Underline if hand written Italics if typed Homo sapiens Genus species Canis lupis Hippocampus erectus

Scientific Name: Genus species If these three species belong to the same genus, they are descended from a common ancestor. Felis domestica domestica Domestic Cat Felis Felis leo leo Lion Felis margarita margarita Sand cat`

A Problem with Traditional Classification Example: The Crab, The barnacle, & The limpet The barnacle and the limpet have similarly shaped shells & look alike The crab has a very different body form Based on anatomy, the barnacle & limpet could be classified together and the crab in a different group.

This incorrect because crabs and barnacles are actually related

Segmentation Free swimming Larva Draw this! Crustaceans Gastropods Molted Exoskeleton Even though they do not look a like, crabs & barnacles are actually related Segmentation Free swimming Larva

Classification Using Cladograms Cladogram: A diagram that shows the evolutionary relationships among a group of organisms.

Segmentation Free swimming Larva Molted Exoskeleton Crustaceans Gastropods Molted Exoskeleton Using Cladograms, you can see that crabs and barnacles share similar characteristics because they both molt & are segmented Segmentation Free swimming Larva

You can also see that ALL have a free swimming larva stage Crustaceans Gastropods Molted Exoskeleton You can also see that ALL have a free swimming larva stage Segmentation Free swimming Larva

Dichotomous Key Statements that describe organisms to help identify them Always start with the first 2 statements

These are T4 Bacteriophage Where do viruses go? Viruses: Are particles of nucleic acid, protein, and in some cases lipids that can reproduce ONLY by infecting living cells. Viruses are made of a core of either DNA or RNA surrounded by a protein coat. These are T4 Bacteriophage A bacteriophage is a virus which infects bacteria

Where do viruses go? (continued) Viruses are not considered alive because they don’t have ALL the characteristics of life. Example: They can’t reproduce independently These are the Influenza Viruses Influenza or "flu" is an infection of the respiratory tract that can affect millions of people every year.

The End.