Short Class Notes On Phylum Coelenterata (Cnidaria)

Phylum Coelenterata (Cnidaria) –

- Aquatic (marine), Sessile or free living.

- Presence of Cnidoblasts or Cnidocytes – Stinging cells.

- Cnidoblasts are for defence, anchorage or predation.

- Tissue level body organisation.

- Diploblastic.

- Central gastro vascular cavity, single opening mouth.

- Two body forms – Polyp (Asexual), Medusa (Sexual) stage.

-eg Hydra, Physalia, Obelia, Aurelia etc.