Phylum- Porifera,Coelenterata/Cnidaria

 Phylum- Porifera

  • Smplest body plan
  • Called as ‘Sponges’. They bear numerous pores on their body -  ‘Ostia’ and ‘Oscula’.
  • Aquatic.
  • Most - marine,  few - fresh water dwellers. 
  • Asymmetrical body.a
  • Have special types of cells- collar cells.
  • Always attached to substratum. 
  • Do not show locomotion. 
  • Sedentary animals.
  • Spongy body is supported by spicules or spongin fibres. 
  • Spicules - made up of calcium carbonate or silica.
  • Feed upon small organisms taken in their body along with water. 
  • Water is taken in through ostia and given out through oscula.
  • Reproduce by budding, and / or by sexual method. 
  • Good ability of regeneration.
  • Examples: Sycon, Euspongia (Bath sponge),Hyalonema, Euplectella, etc.
Phylum - Coelenterata/Cnidaria :
  • Body - cylindrical or umbrella-like. 
  • Cylindrical body -‘Polyp’ 
  • Umbrella like body - ‘Medusa’.
  • Most - marine. 
  • Only few - fresh-water dwellers.
  • Radially symmetrical & diploblastic.
  • Bearing tentacles are present around the mouth. 
  • Tentacles - useful for 
  1. Capturing the prey
  2. Inject the toxin in the body of prey.
  3. For protection too.
  • Examples: Hydra, Adamsia (Sea anemone), Physalia (Portuguese- man-of war),Aurelia (Jelly fish), Corals, etc.