Diversity & Classification
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Transcript of Diversity & Classification
Diversity & Diversity & ClassificationClassification
Objective AObjective AStudents will define the Students will define the
criteria used for classifying criteria used for classifying organisms. organisms.
Understanding Biodiversity….Understanding Biodiversity…. Scientists estimate that there are 5 Scientists estimate that there are 5
million million DIFFERENTDIFFERENT kinds of plants, kinds of plants, animals and microorganisms on animals and microorganisms on earth.earth.
Biodiversity: The variety of Biodiversity: The variety of organisms in a given area.organisms in a given area.
What is taxonomy?What is taxonomy? GROUPINGGROUPING things according to their things according to their
CHARACTERISTICS.CHARACTERISTICS.
GroupsGroups
Kingdom (largest)Kingdom (largest)PhylumPhylumClassClass OrderOrder FamilyFamily GenusGenus Species (smallest)Species (smallest)
Great way to remember: Kids Play Chase On Freeway Get Squished
KingdomKingdom Encompasses large groups; such as Encompasses large groups; such as
plants, animals or fungi. plants, animals or fungi.
PhylumPhylum
Subgroup within a kingdom. Animals Subgroup within a kingdom. Animals belong to the phylum Chordata. belong to the phylum Chordata. (meaning they have a spinal “chord”) (meaning they have a spinal “chord”)
ClassClass
A sub group within a phylum A sub group within a phylum containing common characteristics.containing common characteristics.
OrderOrder
A sub group within a class.A sub group within a class.
FamilyFamily
A sub group with an order.A sub group with an order.
GenusGenus A sub group within a familyA sub group within a family Species with uniquely shared traitsSpecies with uniquely shared traits Species are thought to be closely Species are thought to be closely
related.related.
SpeciesSpecies Unique group of organisms united by Unique group of organisms united by
heredity or interbreedingheredity or interbreeding Defined based on unique featuresDefined based on unique features
Changes over time…. Changes over time…. The classification system has The classification system has
changed over timechanged over time Traditionally used appearance and Traditionally used appearance and
structure to group organismsstructure to group organisms Can cause problems – some groups Can cause problems – some groups
look similar but turn out to be look similar but turn out to be distantly related others that look distantly related others that look different are closely relateddifferent are closely related
FYI: ExampleFYI: ExampleIn 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?What’s in a name?
Creating Scientific NamesCreating Scientific Names Carl Linnaeus – 1750’s Carl Linnaeus – 1750’s Catalog all known speciesCatalog all known species Created two-worded Latin names for Created two-worded Latin names for
each species (Binomial Nomenclature) each species (Binomial Nomenclature)
Binomial Nomenclature Binomial Nomenclature (bie NOH mee uhl Noh muhn KLAY chuhr)(bie NOH mee uhl Noh muhn KLAY chuhr)
Scientific Name = Binomial Nomenclature Scientific Name = Binomial Nomenclature
Genus + Species = Scientific NameGenus + Species = Scientific Name
Example = HumansExample = HumansHomo + Sapien = Homo sapienHomo + Sapien = Homo sapien
Objective BObjective BStudents will be able to Students will be able to
utilize a dichotomous key utilize a dichotomous key to classify organisms.to classify organisms.
We know that this cow is We know that this cow is “Bos Taurus” but…..“Bos Taurus” but…..
““How did How did we get we get there?”there?”
The road to classificationThe road to classification
Requires – keysRequires – keys
Dichotomous KeysDichotomous Keys
Dichotomous KeyDichotomous Key Assists in Identification Assists in Identification Contains pairs of contrasting Contains pairs of contrasting
descriptionsdescriptions The key directs the user to another The key directs the user to another
pair of descriptors orpair of descriptors or Identifies an objectIdentifies an object
Modern Linnaean System Modern Linnaean System Changes over time…Changes over time… Category Domain – has been added Category Domain – has been added
(based on rRNA analysis)(based on rRNA analysis)
3 Broad Groups3 Broad Groups EukaryoteEukaryote
– Multiple chromosomes and a mitotic Multiple chromosomes and a mitotic cycle i.e. animalscycle i.e. animals
ProkaryoteProkaryote– Single-Celled does not have nucleus or Single-Celled does not have nucleus or
membrane-bound structures i.e. membrane-bound structures i.e. bacteriabacteria
ArchaeaArchaea– Prokaryotes in extreme environments Prokaryotes in extreme environments
difference in genetic make up of their difference in genetic make up of their cell call. i.e. bacteria in hot potscell call. i.e. bacteria in hot pots