Classification
&
Biodiversity
Biology Content Standards
2. Cell Biology
Broad Concept:
Concept: Cells have specific structures and functions
that make them distinctive. Processes in a cell can be
classified broadly as growth, maintenance, and reproduction.
2.3 Use cellular evidence (such as cell structure, cell number,
and cell reproduction) and modes of nutrition to describe
six kingdoms (Archaebacteria, Eubacteria, Protista, Fungi,
Plantae, Animalia).
5.2 Describe species as reproductively distinct groups of
organisms. Recognize that species are further classified into a
hierarchical taxonomic system (kingdom, phylum, class, order,
family, genus, species) based on morphological, behavioral,
and molecular similarities. Describe the role that geographic
isolation can play in speciation.
Levels of Classification
Taxonomy
- Kingdom
- Phylum
branch of biology
dealing with the
identification
and naming of
organisms.
(Division-plants)
Carolus Linnaeus
Swedish botanist who devised a system
of grouping organisms into hierarchical
categories based on morphology.
-
Class
Order
Family
Genus
Species
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BINOMIAL NOMENCLATURE
Botanists sometimes
split species into
subsets known as
varieties.
(EX) Peaches and
nectarines are fruits
of the 2 slightly
different varieties of
the peach tree,
Prunus persica.
Taxon Human
A system of 2-part Latin names created by Linnaeus and still in use today.
This is Linnaeus’
’s greatest contribution to biology!
Peach
The scientific name
of an organism consists
of 2 parts:
Genus species.
1ectarine
Lion is Panthera
leo
Sunflower is Helianthus annuus
Why?
KI1GDOM
Animalia
Multicellular, heterotrophic, cell membranes without cell walls
PHYLUM
Chordata
Endoskeleton
Subphylum is Vertebrata – backbone
CLASS
Mammalia
Kingdom Animalia
• Multicellular
Hair, mammary glands
Complex, highly developed brain Sophisticated eyes with stereoscopic vision
Hand with 5 digits including an opposable thumb
Long arms with flexible shoulder and wrist joints
Same 4 types of teeth: incisors, canines, premolars, molars
ORDER
Primates
FAMILY
Hominidae
GE1US
Homo
True human being
SPECIES
sapiens
Wise
Bipedal locomotion
• Eukaryotic
• Cell membranes without cell walls
• Heterotrophs
2
Kingdom Plantae
Kingdom Fungi
• Multicellular
• Multicellular
• Eukaryotic
• Eukaryotic
• Cell walls made of cellulose
• Photosynthetic (Autotrophs)
Kingdom Protista
• Heterotrophs
• Fungi EVER Reproduce by Seeds
• Cell Walls are made of CHITI
Kingdom Archaebacteria
• Unicellular (mostly) & Multicellular
• Unicellular
• Eukaryotic
• Prokaryotic
• Autotrophs &
Heterotrophs
• Autotrophs –
produce food via chemosynthesis – production of carbohydrates through the
use of energy from inorganic molecules instead of light. Their waste products
may include flammable gases such as methane.
or
• Most diverse kingdom!
Heterotrophs
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Kingdom Eubacteria
• Unicellular
Compare & Contrast
Archaebacteria
Bacteria
• Prokaryotic
• Autotrophs & Heterotrophs
THE THREE –DOMAIN SYSTEM
THE THREE – DOMAIN SYSTEM
Highlights the importance of Archaebacteria as a life form
• An alternative to the 6-kingdom system of
classification.
• Domain ARCHAEA the Archaebacteria
• Domain BACTERIA the Eubacteria
• Based on the young science of molecular biology.
• By comparing sequences of ribosomal RA, a
scientist can estimate how long ago pairs of
different organisms shared a common ancestor.
Because all organisms, even prokaryotes, have
ribosomes, rRA can be used to study the degree
of relationship between any two living things.
• Domain EUKARYA Protists, Fungi, Plants, Animals
• Most of the variation in this domain is among the
protists. Surprisingly, when considered from the
perspective of the complete diversity of life on Earth,
the fungi, plants, and animals are quite similar to each
other!
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Taxonomy Today
A running debate in taxonomy is “Which characteristics are biologically most important?”
”
Phylogenetic Tree
A family tree that shows the evolutionary relationship thought to exist
among groups of organisms. It is a hypothesis.
Systematics
Organizes the tremendous diversity of living things in the context of evolution.
• Species shown to be closely related are classified
together.
• Other species that may look alike but possess
analogous structures only are classified in different
groups.
Cladistics
• A relatively new system of phylogenetic classification which
uses certain features of organisms, called SHARED DERIVED
CHARACTERS (features that apparently evolved only within
the group under consideration, for example, birds: feathers),
to establish evolutionary relationships.
• Shared derived characters, particularly a group of several
shared derived characters, are strong evidence of common
ancestry between organisms that share them.
CLADOGRAM – an ancestry diagram developed by
cladistic analysis.
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