Transcript IB-T5-5-Classification

Classification
Unit 5
Mr. Tamashiro
Binomial system of nomenclature
► Designed
by Carolus Linneaus in 18th century
► Based on idea that every species has a Latin
name, made up of two parts
► First part is the name of the genus
► Second part specifies the species
► Name should be printed in italics (underlined
if hand written) and first part capitalized
Example
Humans are Homo sapiens
Hierarchical system of classification
► Organisms
that share
characteristics are
placed into similar
groups
► The
more similar their
characteristics, the
closer the grouping
► The
purpose of
classification is to:
 Clearly identify an organism
with a name that is unique
to the species and avoids
confusion with local naming
 Show evolutionary links
 Allow us to predict
anatomical, physiological
and genetic characteristics it
may share with other
organisms
►
►
►
The Hierarchical system has seven levels
called taxons (plural: taxa)
Each taxon can contain one or more of
the sub-group below it
The seven level hierarchies of taxa are:
1.
2.
3.
4.
5.
6.
Kingdom
Phylum
Order
Family
Genus
Species
Plant Phyla
► Kingdom:
Plantae
► Characteristics:
►Photosynthetic
►Chlorophyll
►Cellulose
cell wall
►Permanent vacuoles
►Stores starch
► Classification
of the major plant phyla is based
on external observables structures
►Need
to know:
-Bryophyta
-angiospermophyta
-Filicinophyta -Coniferophyta
Phylum: Bryophyta
(Mosses, Liverworts, Hornworts)
►
Small terrestrial plants
►
Do not have true roots,
stems or leaves but they
must have structures
resembling them
►
Leaf-like structures are
often arranged in a spiral
►
Usually have live in
clusters which act like
sponges holding water
►
No cuticle
►
Reproductive structures
are called sporangium
which is on long stalks
with capsules on end.
Phylum: Filicinophyta
(ferns)
► Have
true leaves
► New
leaves unroll
► Divided
► Have
leaves
an underground
creeping stem
(rhizome)
► Height
up to 20m
► Reproduction:
sporangia (sori)
contain reproductive
spores
Phylum: Coniferophytes
(conifers & pines)
► All
conifers are woody plants, most are trees
with a single wooden trunk with side
branches
► Leaves are waxy, long thin needles, often
arranged in spirals, often a dark green
colour
► Produce seeds found in cones
► Vascular system (tracheids)
Phylum: Angiospermophyta
(flowering plants and grasses)
► Have
flowers, although
they may be small in
wind-pollinated
angiospermophyta
► Seeds are ovaries
which become the fruit
► Leaves usually as leaf
blade and leaf stalk,
with veins visible on
the lower surface
► Leaves
cuticle
have waxy
► Vascular
bundles
(veins) are made
up of xylem & phloem
Animal phyla
► The
kingdom of animals is classified
according to these characteristics:
►Heterotrophic
►No
cell walls
►No vacuoles
►No chlorophyll
►Store glycogen
► The
ones selected are what might be called
invertebrates (lack of a spinal cord)
► The
six phyla are classified according to features
such as:
 Number of layers in the body plan
 The opening for mouth and anus
 Method of support
Phylogenic studies (evolutionary relationship)
relies on more genetic studies to support the
modern classification of these groups.
Types of symmetry
► About
Symmetries of the Plane
Phylum: Porifera
(sponges)
► No
body layer, rather
there is an aggregate
of different cell types
► Support
is from either
silica or calcium based
spicules which link
together to provide
some support
► Body
plan is built
around water canals
that circulate nutrients
through the sponge for
ingestion by
specialized cells
► There
anus
is no mouth or
Phylum: Cnidaria
(Jelly fish, Sea anemones, Corals)
They have two layers in
the body plan
► There is radial symmetry
► Jelly fish are mobile
organisms. Sea
anemones are sessile
organisms
► Single entrance that
serves the cavity that
functions as circulation
of respiratory gases and
nutrients
►
► These
organisms are
secondary consumers
and posses stinging
cells with toxins called
nematocysts to disable
prey
► Corals
secrete a CaCO3
skeleton
Phylum: Platyhelminthes
(flatworms)
►3
layers in the body plan
► One entrance to “gut” which can have many
folds to increase surface area.
► Largely parasitic, includes flukes
Phylum: Annelida
(segment worms)
►3
layers to the body
plan
► Bilateral
► Body
symmetry
is divided into
ringed segments with
some specialization of
segments
► Mouth
is connected via
gut to a separate anus
► Skin
surface is used for
gas exchange
► Many
marine forms but
also terrestrial species,
usually soil burrowing
Phylum: Mollusca
(Snails, Slugs, Octopus)
► Bilateral
symmetry with significant modification
► Body plan has three major features
 Foot, a muscular structure used for movement and
burrowing
 Central visceral mass, contains all the organ structures
(separate mouth & anus)
 Mantle, a folded membrane structure that can surround
other tissues and create a cavity containing ag ill. The
mantle frequently secretes a calcareous shell.
Phylum: Arthropoda
(Insects, Crustaceans, Spiders,
Scorpions, Millipedes)
►
3 layer body plant with
bilateral symmetry
►
At least 3 pairs of jointed
legs
►
Hard exoskeleton
composed of chitin
►
Some flying organisms in
the class Insecta
►
Jointed body segments
►
Separate mouth and anus
►
Jointed appendages to
each segment
►
Many free-living but also
some parasitic
Dichotomous Keys
►
►
►
►
►
►
Each questions divides the group of organisms into two
smaller groups based on a pair of alternative
characteristics
Subsequent groups may focus on more minor details
In most cases the characteristic will be readily observed or
measurable
It is better to choose characteristics that are uninfluenced
by environmental variation
Shape and number are often good characteristics on which
to base alternative pairings
A complete key will have each type of organisms being
classified separated with a final identifying name
Pamishan Creatures
Go to the following link this shows how the
same creatures you had a close encounter
with last year (Allien Periodic Table) finally
made it to earth so now we are trying to
classify them and to do so we use a
Dichotomous Key:
Pamishan Creature Taxonomy