Notes on Classification/Taxonomy

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

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 HawkHoney BuzzardTurkey Vulture

Another Example: Dolphin Dolphin Tursipos truncatus Mahi mahi

Taxonomy – science of classifying living organisms “Father of Taxonomy” – Carolus Linnaeus (Swedish Botanist)

he set up the system we use today he recognized species on the basis of structural similarity

he gave them scientific names made up of Latin words

This system is called binomial nomenclature (two-word naming) the first word is the genus (which is always capitalized) and the second is the species Rosa gallica both are underlined or italicized

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

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

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

Are these animals members of the same species? X= horsedonkeymule (sterile) No

In taxonomy, a group or level of organization is called a taxonomic category or taxon.

Organizing the Taxa Domain Kingdom Phylum Class Order Family Genus Species All living things

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

Human Classification Domain Eukarya Kingdom Animalia Phylum Chordata Subphylum Vertebrata Class Mammalia Order Primates Family Hominidae Genus: Homo Species: sapiens

Scientific name of man - Homo sapiens (wise man)

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

New Species Video Clips Classification (4 min) New Species (1 min)

The Three-Domain System There are 3 Domains: Domain Bacteria Domain Archaea Domain Eukarya There are 6 Kingdoms: (in order from least complex) Eubacteria Protista ArchaebacteriaFungi Plantae Animalia

The Three-Domain System Domain Bacteria Kingdom Eubacteria Domain Archaea Kingdom Archaebacteria Domain Eukarya Kingdoms Protista, Fungi, Plantae, Animalia

Kingdom Archaebacteria Unicellular Prokaryote Cell walls withOUT Peptidoglycan Autotrophic or heterotrophic Extremophiles – Love extreme environments like inside the guts of animals, volcanoes, hydrothermal vents, and hot springs Archaea Hydrothermal Vent Hot Springs Volcanoes

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

Kingdom Protista Unicellular or Multicellular eukaryote Autotrophic or heterotrophic Some have cell walls of cellulose and chloroplasts Live either solitary or in colonies Amoeba Euglena Paramecium Video Clip: Amoeba

Kingdom Fungi Unicellular or Multicellular eukaryote Cell walls made of Chitin Heterotrophs Yeast Mushrooms

Kingdom Plantae Multicellular eukaryote Cell walls made of Cellulose Contain chloroplasts Autotrophs nonmotile Trees & Grass Moss Venus Fly Trap

Kingdom Animalia Multicellular eukaryote NO cell walls or chloroplasts Heterotrophs Motile (at least for some part of their life cycle) Worms Insects Jellyfish Giraffes

3 Domains – 6 Kingdoms “Tree of Life” Cladogram

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 - capsid. These are T4 Bacteriophages A bacteriophage is a virus which infects bacteria

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 protein in the capsid “tricks” the host cell into allowing the virus inside once inside it takes over, putting the genetic program of the virus into effect

Common diseases caused by viruses: Polio,measles,AIDS,mumps, influenza,yellow fever,rabies, common cold,cancer

Body cavity - coelom A coelom is a true, main body cavity that surrounds internal organs Body Cavities

it is important in classifying animals and in the study of evolution

Symmetry – general form of an organism 3 basic types: (except in snails and amoeba which are asymmetrical) Symmetry

1. Spherical – a ball (sphere) any axis through the center will divide in half

2. Radial – axes radiate like the spokes of a wheel

3. Bilateral – 2 sided axis will divide into similar halves one side is a mirror image of the other

Body regions for bilateral symmetry: dorsal – back or upper surface ventral – stomach (abdomen) or lower surface anterior – front end posterior – hind or rear end (tail, caudal)

medial – towards the midline lateral - side proximal – part of the appendage which is attached distal – part of the appendage which is free

dorsal ventral posterior anterior medial lateral proximal distal

Reproduction 2 types of reproduction: 1. Asexual – the formation of offspring without the fusion of sperm and egg (gametes) in most cases, the offspring are genetically identical to the parent

only needs one organism to produce offspring

Types of Asexual Reproduction a. Binary fission – genetic material is copied and then distributed to new identical cells Examples: bacteria and some protists

b. Budding – outgrowth form from the parent that eventually pinch off to form new individual Examples: yeast and hydra

c. Spore formation – production of many spores from a primary spore cell Example - fungi

d. Regeneration – the ability to replace lost or injured body parts Examples – starfish and planaria

2. Sexual – involves the fusion of sperm and egg (gametes) offspring are not genetically identical to parents two parents are needed to produce offspring