Transcript CLASSIFICATION

CLASSIFICATION
Why Do We Classify
Organisms?
• Organize
• Recognize
relationships
• To study the
evolutionary
history
(phylogeny).
History of Classification?
ARISTOTLE
• Greek philosopher
• Divided organisms
into 2 groups
Plants and Animals
• Divided animals into
groups
– 1. walking
– 2. flying
– 3. swimming
History of Classification
Carolus Linnaeus
• Classified plants and
animals according to
similarities in structure
• Divided living things into
one of two kingdoms
– Plant or Animal
• Divided each of the
kingdoms into smaller
groups called
– Genera (genus)
• Divided each genera into
smaller groups called
– species
The Evolution of Our
Classification System
• The Linnaean System
– used by scientists all over the world
– expanded to include new and different living things
– will continue to grow as human knowledge grows
Classification Terminology
• CLASSIFICATION –
• Grouping things based on
their similarities.
• TAXONOMY –
• The science of classifying
organisms.
• ORGANISM –
• Any living thing.
• BINOMIAL
NOMENCLATURE –
• A two-part scientific name
(Genus species).
• EVOLUTION –
• Species change gradually
over time.
Our Current
Classification System
• Specific groups
based on
– Similarities and
differences in body
structure
– DNA
– Behavior
– Other?
Our Current
Classification System
• The largest group
– kingdom
• Followed by
–P
–C
–O
–F
–G
–S
Our Hierarchical System
• Taxonomists divide
organisms into a
series of groups
(divisions) that get
more and more
specific.
– Kingdoms include
the largest numbers
of organisms.
– Species include only
one type of organism.
• Moving from
kingdom to species
• For example, two organisms in the
same order have more in common
than two organisms in the same
class.
– groups increase in
commonality and
evolutionary
relationships, but
decreasing in size
(fewer numbers).
The 5 Kingdoms
Moneran Kingdom
• Bacteria
– oldest living organisms on Earth
– Microscopic
– unicellular
– Prokaryotes
– Heterotrophs and autotrophes
– found in the ground, water and in other living
organisms
Structure of Bacteria
Harmful Bacteria
• In human hosts, bacteria
cause
– tetanus
– pneumonia,
– strep throat
• Humans can be treated
with antibiotics
• Sterilization and
disinfectants can help
prevent infection
Helpful Bacteria
• Produces food
– Yogurt
– Sauerkraut
• Helps digest food
– E. coli in intestines
• Keeps the soil
fertile
– Decomposes dead
organisms
The Kingdom Debate
• Some scientists
separate the
Moneran Kingdom
into two kingdoms
– Based on chemical
makeup
Archaebacteria vs. Eubacteria
• Archaebacteria
– “ancient bacteria”
– “extremophiles”
• Found in harsh
conditions such
as volcanic vents
at the bottom of
the sea
• Eubacteria
– “true bacteria”
– blue-green algae
– Most bacteria are in this
kingdom
Protist Kingdom
• Odds and ends kingdom
• Unicellular/Multicellular
• Heterotrophic/Autotrophic
• Eukaryotic (nucleus)
• Live in water, soil or
humans
Classification of Protists
Protozoans
Animal-like
heterotrophs
ex. Amoeba and Paramecium
Algae
Plant-like
Autotrophs
Ex. Volvox and Giant Kelp
Fungi Kingdom
• Multicellular
– Mushrooms, mold,
mildew
• Unicellular
– Yeast only
• Eukaryotic
• Heterotrophs
– Absorb dead things
The Importance of Fungi
• Decomposers
– Break down dead
organisms
– Return nutrients to the
soil
• Drugs are produced
– penicillin
• Food supply
– mushrooms, truffles
• Yeast
– Fermentation which
makes alcohol and
produces carbon dioxide
to make bread
Bad Fungi?
• Animal diseases
– ringworm
– athlete's foot
• Plant diseases
– rusts
– smuts
– leaf, root, and
stem rots
Plant Kingdom
• Multicellular
• Eukaryotes
• Autotrophs
– make food through the
process of photosynthesis
• Examples
– ferns, flowers, shrubs
– Trees
• Conifers
• Deciduous
Animal Kingdom
•
•
•
•
Multicellular
Eukaryotes
Heterotrophs
Examples
– Insects
– Star fish
– Humans
Animal Kingdom
Invertebrates
Vertebrates
The Organization of Life . . .