Classification and Taxonomy

The student will investigate and understand how

organisms can be classified. Key concepts include:

a) the distinguishing characteristics of

kingdoms of organisms; b) the distinguishing

characteristics of major animal and plant

phyla; and c) the characteristics of

the species.

TAXONOMY--the branch of science that classifies and names living things.

How are Living things classified?

• physical structure (how they look)• evolutionary relationships • embryonic similarities (embryos)• genetic similarities (DNA)• biochemical similarities

Classification Systems

HOW ARE LIVING THINGS NAMED?

NOMENCLATURE--a system for naming things

BINOMIAL NOMENCLATURE a two word naming system used in Biology to name organisms.Carolus Linnaeus devised this in the 1800's using these two subgroups for the name(uses Latin- a ‘universal’ language)

GENUS & SPECIES(more general) (more specific)* Humans are known as Homo sapiens

Kingdom AnimaliaPhylum Chordata Class Mammalia Order Primates Family Hominidae Genus Homo species sapiens

Eukaryotic vs. Prokaryotic CellsEukaryotic Cells• Large• Have chromosomes• Have membrane-bound

organelles– Nucleus– Mitochondria– Centrioles– (theory of

endosymbiosis)

Prokaryotic Cells• Small• No chromosomes,

only small circle of DNA (plasmid)

• No membrane-bound organelles.

Eukaryotic Cells are Larger than Prokaryotic cells

MONERA• Only kingdom composed of prokaryotic organisms• Single cell (no multicellular forms)• Have a cell wall• No membrane-bound organelles • Autotrophic or Heterotrophic

(ex- Bacteria, some algae)

The Archaebacteria, the most ancient of this kingdom, are so differentthat they may belong to a separate kingdom.

Other groups of Monera include the cyanobacteria (autotrophic) and eubacteria (heterotrophic).

PROTISTA• The most ancient eukaryotic kingdom• Eukaryotic • heterotrophic, autotrophic, or both• Perhaps they are best defined as

eukaryotes that are NOT fungi, animals, or plants.

(Ex- Amoeba, Paramecium, Euglena)

FUNGI• Eukaryotic, heterotrophic, usually

multicellular group having multinucleated cells enclosed in cells with cell walls.

• Decomposers: They obtain their energy by decomposing dead and dying organisms and absorbing their nutrients from those organisms.

• Some fungi also cause disease (yeast infections, rusts, and smuts), while others are useful in baking, brewing, as foods, drugs and sources for antibiotics.(Ex- mushrooms, yeast)

PLANTAE

• Plants are immobile, multicellular eukaryotes that produce their food by photosynthesis (autotrophic)and have cell walls.

• Plants are important sources of oxygen, food, and clothing/construction materials, as well as pigments, spices, dyes, and drugs.

ANIMALIA• Animals are multicellular, heterotrophic

eukaryotes that are capable of mobility at some stage during their lives, and that have cells lacking cell walls.