Phylum-Nematoda

Animals are marine, fresh water or terrestrial parasitic worm.

Body is cylindrical, bilaterally symmetrical and covered by cuticle covering.

Body show adaptations for parasitic mode of life.

Body –cavity is pseudocoel.

Digestive system is complete with mouth and anus.

Respiration takes place by gaseous exchange. Circulatory system is absent.

Sexual reproduction is found.  Sexes are separate. Internal fertilization occurs.

Ex- Ascaris  etc.

Ascaris Male & Female