1. Taxonomy is the science of classification of organisms and involves classifying them into a hierarchical taxonomic system of kingdoms, phyla, classes, orders, families, genera, and species based on their shared characteristics.
2. Organisms are classified for several advantages including making the study of living things easier, helping with identification, and indicating evolutionary relationships.
3. The animal kingdom is divided into major phyla including porifera, cnidaria, platyhelminthes, nematoda, annelida, arthropoda, mollusca, echinodermata, and chordata. Each phylum contains many distinctive characteristics in terms of body structure, symmetry, and level of organization
2. Texono
my
Classification/Alignme
nt
Comes From Greek Language “Taxis” which means
'arrangement' & “Nomia” which means ‘Method’
Naming groups of biological organisms
principal ranks kingdom, phylum(division is sometimes used in
botany in place of phylum), class, order, family, genus,
and species.
“The science of classification, in biology the arrangement of
organisms into a classification”
father of taxonomy- Swedish botanist Carl Linnaeus
Aristotle, John Ray and Carolus Linnaeus are the notable
names in the history of classification
3. Advantages of
Classification/Why
Classification is
Important?
It makes the study of living organisms easier.
It helps in the specific identification of any given organism.
The study of a few representatives from each distinct group helps us to
know about the characterstic features of organisms of that group.
It indicates the evolutionary relationship between different groups of
organisms.
5. Porifera
Cnideria
Platyhelminthes
Nematoda
Annelida
Arthropoda
Mollusca
Echinodermata
Cordata
includes organisms with holes
Primitive multicellular animals and have cellular level of
organisation.Non-motile animals attached to some solid support
body design involves very minimal differentiation and
division into tissues.
Commonly called sponges
Have a water transport or canal system
Sexes are not separate (hermaphrodite), i.e., eggs and
sperms are produced by the same individual.
Sponges reproduce asexually by fragmentation
and sexually by formation of gametes.
Sycon (Scypha), Spongilla (Fresh water
sponge) and Euspongia (Bath sponge).
6. Porifera
Cnideria
Platyhelminthes
Nematoda
Annelida
Arthropoda
Mollusca
Echinodermata
Cordata
The name Cnidaria is derived from the cnidoblasts
Cnidoblasts are used for defense and for the capture of prey
Coelenterata (Cnidaria) are aquatic, mostly marine sessile or free-
swimming radially symmetrical
They are diploblastic.
Some of these species live in colonies (corals).
Some have a solitary [living alone] (hydra).
Some of the cnidarians, e.g., corals have a skeleton composed of
calcium carbonate.
Digestion is extracellular and intracellular.
Examples: Aurelia (jelly fish), Physalia (Portuguese man-of-war),
Adamsia (Sea anemone), Pennatula (Sea-pen), Gorgonia (Sea-fan)
and Meandrina (Brain coral).
7. Porifera
Cnideria
Platyhelminthes
Nematoda
Annelida
Arthropoda
Mollusca
Echinodermata
Cordata
More complexly designed than the earlier groups
bilaterally symmetrical
triploblastic
The body is flattened dorsiventrally, meaning from top to
bottom, which is why these animals are called flatworms.
parasitic. Hooks and suckers are present in the
parasitic forms.Acoelomate: There is no true internal body cavity or coelom, in
which well developed organs can be accommodated.
Specialised cells called flame cells help in osmoregulation and
excretion.Sexes are not separate.
Fertilisation is internal and development is indirect.
8. Porifera
Cnideria
Platyhelminthes
Nematoda
Annelida
Arthropoda
Mollusca
Echinodermata
Cordata
Body is cylindrical [bilaterally symmetrical] rather than flattened.
there are tissues, but no real organs].
Triploblastic. A sort of body cavity or a pseudocoelom, is
present.freeliving, aquatic, terrestrial or parasitic in plants and animals.
These are very familiar as parasitic worms causing diseases
The body is circular in cross-section, hence, the
name roundworms.
An excretory tube removes body wastes from the body cavity
through the excretory pore.
Sexes are separate (dioecious), i.e., males and females are
distinct.
Often females are longer than males.
Fertilisation is internal and development may be direct
9. Porifera
Cnideria
Platyhelminthes
Nematoda
Annelida
Arthropoda
Mollusca
Echinodermata
Cordata
Aquatic [marine and fresh water] or terrestrial; free-living, and
sometimes parasitic.
Exhibit organ-system level of body organization
Coelomate [true body cavity].
Bilateral symmetric and triploblastic
They possess longitudinal and circular muscles which help in
locomotion.
A closed circulatory system is present.
Nephridia (sing. nephridium) help in osmoregulation and
excretion
Reproduction is sexual.
10. Porifera
Cnideria
Platyhelminthes
Nematoda
Annelida
Arthropoda
Mollusca
Echinodermata
Cordata
Arthropods have hard, external shells called “exoskeletons,”
segmented bodies and jointed legs
They exhibit organ-system level of organisation.
bilaterally symmetrical, triploblastic
body consists of head, thorax and abdomen.
There is an open circulatory system, and so the blood does not
flow in well defined blood vessels.
Respiratory organs are gills, book gills, book lungs or tracheal
systemSensory organs like antennae, eyes (compound and
simple), balance organs are present.
Fertilisation is usually internal
Development may be direct or indirect
Examples are prawns, butterflies, houseflies, spiders, scorpions
and crabs
11. Porifera
Cnideria
Platyhelminthes
Nematoda
Annelida
Arthropoda
Mollusca
Echinodermata
Cordata
Second largest animal phylum. They are terrestrial or aquatic.
Exhibit organ-system level of organization
Bilaterally symmetrical, triploblastic, coelomate animals. There is
little segmentation.
Have an open circulatory system and kidney-like organs for
excretion. The anterior head region has sensory tentacles.
mouth contains a file-like rasping organ for feeding,
called radulaA soft and spongy layer of skin forms a mantle over the visceral
hump.Examples are octopus, snails and mussels.
12. Porifera
Cnideria
Platyhelminthes
Nematoda
Annelida
Arthropoda
Mollusca
Echinodermata
Cordata
Have an endoskeleton
Exclusively free-living marine animals with organ-system
level of organisation.
Triploblastic with a coelomic cavity [coelomate animals]. The
adult echinoderms are radially symmetricalbut larvae
are bilaterally symmetrical.Water-driven tube system [water vascular system] are used for
locomotion, capture and transport of food and respiration.
Coelomate animals
Digestive system is complete. An excretory system is absent
Sexes are separate. Reproduction is sexual. Fertilisation is
usually externalDevelopment is indirect with free-swimming larva.
Examples: Star fish, Sea urchin, Sea lily, Sea cucumber, Brittle
star.
13. Porifera
Cnideria
Platyhelminthes
Nematoda
Annelida
Arthropoda
Mollusca
Echinodermata
Cordata
Fundamentally characterised by the presence of a
notochord, a dorsal hollow nerve cord and paired
pharyngeal gill slits.
Bilaterally symmetrical, triploblastic,
coelomate with organ-system level of organisation
They possess a post anal tail and a closed circulatory
system.Divided into three subphyla: Urochordata or Tunicata,
Cephalochordata and Vertebrata
Subphyla Urochordata and Cephalochordata are often
referred to as protochordates and are
exclusively marine.
Examples: Urochordata – Ascidia, Salpa, Doliolum;
Cephalochordata – Amphioxus or Lancelet.
14. BODY SYMMETRY
• SYMMETRY IS THE ARRANGEMENT
OF BODY PARTS AROUND A
CENTRAL PLANE OR AXIS
• ASYMMETRY OCCURS WHEN THE
BODY CAN’T BE DIVIDED INTO
SIMILAR SECTIONS (SPONGES)
15. 5 Main Types of Symmetry Seen in
AnimalsAsymmetrical Symmetry (অপ্রতিসম)
Spherical Symmetry (গ োলীয় প্রতিসোময)
Radial Symmetry
Biradial Symmetry
Bilateral Symmetry(তিপোতশিক)
12345
16. Asymmetrical Spherical RadialBiradialBilateral
No body axis and no plane
of symmetry
Only members of the
phylum Porifera (sponges)
have no body plan symmetry
There are some fish
species, such as flounder,
that lack symmetry as
adults. However, the larval
fish are bilaterally
symmetrical.
17. AsymmetricalSpherical RadialBiradialBilateral
Shape of the body is
spherical and lack any
axisThe body can be divided into two
identical halves in any plane that
runs through the organism’s cen-
tre
এক হালি ভরে দে ”
এক দে - একরকাষী প্রাণী
হালি দে- দহলিওর ায়া
ভ দে - ভিভক্স
দে দে - দেলিওিালেয়া
18. Asymmetrical SphericalRadialBiradialBilateral
Radial symmetry occurs when body parts are arranged around a
central point like spokes on a wheel (echinoderms)
Most animals with radial symmetry are sessile (attached) or
sedentary (move very little)
19. Asymmetrical SphericalRadial Biradial Bilateral
Bilateral symmetry occurs
when animals can be
divided into equal halves
along a single plane
Organisms will have right
and left sides that are mirror
images of each other
More complex type of
symmetry