Classification of Animal Kingdom

Classification of Animal Kingdom

Animals kingdom of the world is divided into two sub-kingdoms :
1. Unicellular animal
2. Multi-cellular animal or Metazoans

Unicellular animals are kept in a single phylum Protozoa whereas multi- cellular animals are divided into 9 phylums.

Classification of animals according to Storer and Usinger -

1. Phylum Protozoa

» They are Unicellular.
» It's body is made of only one cell.
» There is one or more nuclei in its cytoplasm.
» It is parasitic and free living.
» All the metabolic activity (eating, digestion, respiration, excretion, reproduction) takes place in unicellular body.
» Respiration and excretion take place by diffusion.
Example - Amoeba, Euglena, Trypanosoma etc.

2. Phylum Porifera

All animal of this group are found in marine water & bear pores in body.
» These are multi cellular animals but cells do not make regular tissues.
» Numerous pores known as ostia found on body wall.
» Skeleton is made up of minute calcareous or silicon spicules.
Example -Sycon, Sponge etc.

3. Phylum Coelenterate

» Coelenteron is present inside body.
» Animals are aquatic and diploblastic.
» Around the mouth some thread-like structure are found known as tentacles, which help in holding the food.
» Body radial symmetry.
» Specialized cnidoblast cell are found help in catching the food.
Example - e-Hydra, Jellyfish, Sea Anemone etc.

4. Phylum Platyhelminthes

» Its a Flat worm
» Triploblastic and nobody cavity.
» Dorso-ventraly flattened animal.
» Alimentary canal with single opening, anus absent.
» Excretion takes place by flame cells.
» There is no skeleton, respiratory organ, circulatory system etc.
» These are hermaphrodite animal.
Example - Planaria, Liver fluke, Tape worm etc.

5. Phylum Aschelminthes

» Its a Round worm
» Long, cylindrical, unsegmented worm.
» Bilaterally symmetrical and triploblastic.
» Alimentary canal is complete in which mouth and anus both are present.
» There is no circulatory and respiratory systems but nervous system is developed.
» Excretion takes place through Protonephridia.
» They are unisexual.
» Most form are parasitic but some are free living in soil and water.
Example - Round worm, like - Ascaris, Thread worm, Wuchereia etc.

1. Enterobius (pin worm/thread worm) - It is found mainly in the anus of child. Children feel itching and often vomits. Some children urinate on the bed at night.
2. Filarial disease is caused by Wuchereia bancrofti.

6. Phylum Annelida

» It is Annulus body Bearing ring.
» Body is long, thin, soft and metamerically segmented.
» Locomotion takes place through Setae made up of Chitin.
» Alimentary canal is well developed.
» Normally respiration through skin, in some animals it takes place through gills.
» Nervous system is normal and blood is red.
» Excretion by nephridia.
» True coelom is present.
» Both unisexual and bisexual.
Example -Earthworm, Nereis, Leech etc.

7. Phylum Arthropoda

» It is Jointed leg.
» Body is divided into three parts - Head, Thorax and Abdomen.
» Body is covered with a thick chitinous exoskeleton.
» Circulatory system is open type.
» Its body cavities are called haemocoel.
» Tracheai, book lungs, body surface are respiratory organ.
» These are mainly unisexual and fertilization takes place inside the body.
Example - Cockroach, prawn, crab, bug fly, mosquito, bees etc. 1. There are six feet and four wings in insects.
2. There are 13 chamber in the Cockroach's heart.
3. Ant is a social animal which reflects labour division.
4. Termite is also a social animal which lives in colony.
5. The main excretory organ of insects are malpighian tubules.

Phylum Mollusca

» It is Soft bodies animal.
» All the animals in this group are marine.
» Water vascular system is present.
» There is Tube feet for locomotion, taking food which works as sensation organ.
» Brain is not developed in nervous system.
» There is a special capacity of regeneration.
Example -Star fish, Sea urchin, Sea cucumber, Brittle stars etc.

1. The function of the Aristotle lantern is to chew the food.
2. It is found in sea urchin.