Chapter 17 Lecture Notes

Classification
Classification is the grouping of objects based on similarities.

Taxonomy
Taxonomy is the biological study of classification.

Taxonomist is a biologist that studies taxonomy.

Aristotle (384-322 BC)
He was the first to classify living things.
Two major groups: plants and animals.
Further classified by size or the way they lived.
So bats, birds, & bees were all grouped together because they fly.
Not a good system!


Carolus Linnaeus (1707-1779)
He developed the classification system that we use today.
System based on how closely related organisms are.
Gave each organism 2 Latin names.
This is called binomial nomenclature.

Binomial Nomenclature
Every organism has a two part name!
This name is also called scientific name or the genus species name.
It is always italicized or underlined.
Scientific names are in Latin (dead language)

Man = Homo sapiens

species (always lowercase)
genus (always capitalize)

Bobcat = Lynx rufus

Why should we classify?
Common names can be confusing!
(Ex: Sea horse)
Makes it easier for scientists to communicate all over the world.
Classification provides a framework of logic and order so that we can see the relationships between living things.

Biologists would have serious problems if organisms were not classified.
Poisonous mushroom
Pacific Yew tree – Taxol, cancer drug

How are living things classified?
Organisms are broken down into categories called taxa.
Kingdom
Phylum
Class
Order
Family
Genus
Species

Human Classification
Kingdom Animalia
Phylum Chordata
Class Mammalia
Order Primates
Family Hominidae
Genus Homo
Species Sapiens

How are the relationship determined?
1. Phylogeny (evolutionary history)
2. Development
3. Biochemistry (DNA stuff)
4. Behavior


Prokaryote: cell lacks a true nucleus or membrane-bound internal organelles (Ch. 8)
Eukaryote: cells having a true nucleus and membrane-bound internal organelles (Ch. 8)

The Six Kingdoms
1. Archaeobacteria
Bacteria that live in extreme environments (deep sea vents)


2. Eubacteria – the bacteria that can make you sick
Ex: strep throat
E-coli

Old Way – 5 Kingdoms!
Archaebacteria and Eubacteria used to be one kingdom called Monera.

3. Kingdom Protista
Eukaryotes (unicellular or multicellular)
Lack Complex Organ Systems
Live in water or moist environments

4. Kingdom Fungi
“Earth’s Decomposers”
Eukaryotes (unicellular or multicellular)
Obtain food by absorption (heterotrophic)

5. Kingdom Plantae
“Earth’s Multicellular Oxygen Producers”
Eukaryotes
Produce their own food (photosynthesis)
Stationary
Cells have Cell Walls made of cellulose

6. Kingdom Animalia
Multicellular Consumers
Eukaryotes
Cells Lack a Cell Wall