What is a dichotomous key? a tool that determines the identity of items in the natural world, such as trees, wildflowers, mammals, reptiles, rocks, and fish. Keys consist of a series of choices that lead you to the correct name of a given item. "Dichotomous" means "divided into two parts".

Taxonomy Unit 4-Part 2 The science of naming organisms.

Classification When organisms are assigned to groups within a system of categories distinguished by how they look, origin, etc.

Carolus Linnaeus He described organisms with two word names. This is called binomial nomenclature. 1 st word Genus name (capital) 2 nd word Species name (lowercase)

Example of Scientific Names Homo sapien (human genus and species name) Canis lupus (dog genus and species name) Felis domesticus (cat genus and species name)

Taxonomic Hierarchy Names organisms and their relationships from complex to specific.

All organisms classified in a Taxon Kingdom (BROADEST- 6 kingdoms) Phylum Class Order Family Genus Species (MOST SPECIFIC- one million species discovered each day!!) Kings Play Cards on Fat Green Stools.

Grizzly bearBlack bearGiant panda Red fox Abert squirrel Coral snake Sea star KINGDOM Animalia PHYLUM Chordata CLASS Mammalia ORDER Carnivora FAMILY Ursidae GENUS Ursus SPECIES Ursus arctos Section 18-1 Figure 18-5 Classification of Ursus arctos

HUMAN TAXON Kingdom Animalia Phylum Mammalia Class Chordates Order Primates Family Homindae Genus Homo Species----- sapien

Kingdoms Eubacteria Archaebacteria Protista Plantae Fungi Animalia DOMAIN EUKARYA DOMAIN ARCHAEA DOMAIN BACTERIA Section 18-3 Cladogram of Six Kingdoms and Three Domains

DOMAIN KINGDOM CELL TYPE CELL STRUCTURES NUMBER OF CELLS MODE OF NUTRITION EXAMPLES Bacteria Eubacteria Prokaryote Cell walls with peptidoglycan Unicellular Autotroph or heterotroph Streptococcus, Escherichia coli Archaea Archaebacteria Prokaryote Cell walls without peptidoglycan Unicellular Autotroph or heterotroph Methanogens, halophiles Protista Eukaryote Cell walls of cellulose in some; some have chloroplasts Most unicellular; some colonial; some multicellular Autotroph or heterotroph Amoeba, Paramecium, slime molds, giant kelp Fungi Eukaryote Cell walls of chitin Most multicellular; some unicellular Heterotroph Mushrooms, yeasts Plantae Eukaryote Cell walls of cellulose; chloroplasts Multicellular Autotroph Mosses, ferns, flowering plants Animalia Eukaryote No cell walls or chloroplasts Multicellular Heterotroph Sponges, worms, insects, fishes, mammals Eukarya Classification of Living Things Section 18-3 Key Characteristics of Kingdoms and Domains

Name that Kingdom…

Peptidoglycan Cell wall Cell membrane Ribosome Flagellum DNA Pili Section 19-1

What are the 6 Kingdoms? Archaebacteria Eubacteria Protists Fungi Plants Animals

DO NOW What are 3 ways you can group the salamanders? Example—they all have spots

What is a species? The basic unit of classification.

How many species are out there? Scientist currently estimate that: –There are 10 million species worldwide. –Over 5 million live in the tropics. –Most unnamed species are small or microscopic.

Why is taxonomy useful? Helps to prevent confusion among scientist. Helps to show how organisms are related.

What are populations? A group of interbreeding individuals that live in the same place at the same time, and compete with each other for food, water, shelter and mates. What happens if a population produces more offspring than it can support?

What is a cladogram? A graph showing when different groups diverged from a common ancestral line. Flowering plants Cone-bearing plants Ferns and their relatives Mosses and their relatives Green algae ancestor Flowers; Seeds Enclosed in Fruit Seeds Water-Conducting (Vascular) Tissue

Invertebrate Cladogram Radial Symmetry Deuterostome Development Coelom Pseudocoelom Protostome Development Radial Symmetry Three Germ Layers; Bilateral Symmetry Tissues Multicellularity Echinoderms Arthropods Annelids Mollusks Roundworms Flatworms Cnidarians Sponges Single-celled ancestor

Chordate Cladogram Nonvertebrate chordates Fishes Amphibians Reptiles Birds Mammals Invertebrate ancestor