Download Classification

Diversity &
Classification
Objective A
Students will define the
criteria used for classifying
organisms.
Understanding Biodiversity….
 Scientists
estimate that there are 5
million DIFFERENT kinds of plants,
animals and microorganisms on
earth.
 Biodiversity: The variety of
organisms in a given area.
What is taxonomy?

GROUPING things according to their
CHARACTERISTICS.
Groups
Kingdom
(largest)
Phylum
Class
 Order
 Family

Genus

Species (smallest)
Great way to remember: Kids Play Chase On Freeway
Get Squished
Kingdom
 Encompasses
large groups; such as
plants, animals or fungi.
Phylum
 Subgroup
within a kingdom. Animals
belong to the phylum Chordata.
(meaning they have a spinal “chord”)
Class
A
sub group within a phylum
containing common characteristics.
Order
A
sub group within a class.
Family
A
sub group with an order.
Genus
A
sub group within a family
 Species with uniquely shared traits
 Species are thought to be closely
related.
Species
 Unique
group of organisms united by
heredity or interbreeding
 Defined based on unique features
Changes over time….
 The
classification system has
changed over time
 Traditionally used appearance and
structure to group organisms
 Can cause problems – some groups
look similar but turn out to be
distantly related others that look
different are closely related
FYI: Example
In a sense, birds are dinosaurs!
Scientists
think that modern
birds are descended from a
subgroup of dinosaurs –
theropods.
They
base this information
on comparisons of modern
birds and fossilized
theropods.
What’s in a name?
Creating Scientific Names
 Carl
Linnaeus – 1750’s
 Catalog all known species
 Created two-worded Latin names for
each species (Binomial Nomenclature)
Binomial Nomenclature
(bie NOH mee uhl Noh muhn KLAY chuhr)
 Scientific
Name = Binomial Nomenclature
Genus + Species = Scientific Name
Example = Humans
Homo + Sapien = Homo sapien
Objective B
Students will be able to
utilize a dichotomous key
to classify organisms.
We know that this cow is
“Bos Taurus” but…..
“How did
we get
there?”
The road to classification
Requires – keys
Dichotomous Keys
Dichotomous Key
 Assists
in Identification
 Contains pairs of contrasting
descriptions
 The key directs the user to another
pair of descriptors or
 Identifies an object
Modern Linnaean System
 Changes
over time…
 Category Domain – has been added
(based on rRNA analysis)
3 Broad Groups
 Eukaryote
– Multiple chromosomes and a mitotic
cycle i.e. animals
 Prokaryote
– Single-Celled does not have nucleus or
membrane-bound structures
i.e. bacteria
 Archaea
– Prokaryotes in extreme environments
difference in genetic make up of their
cell call. i.e. bacteria in hot pots