4. Kingdom Animalia - part 04 -Phylum : Ctenophora

 

4. Kingdom Animalia - part 04 -Phylum : Ctenophora


Phylum : Ctenophora :

  • These are commonly called comb jellies or sea walnuts. 
  • These are exclusively marine, free swimming animals. 
  • Body is diploblastic, radially symmetrical with blind-sac body plan. 
  • Animals have tissue-level organisation. 
  • Locomotion is carried out by eight rows of cilliated comb plates. 
  • Characteristic feature of ctenophores is bioluminescence. 
  • Like cnidarians, ctenophores also exhibit extra and intracellular digestion. 
  • Reproduction is sexual with indirect development. 
  • Cnidoblasts are absent hence these are called acnidarians.
  • Instead, they have colloblasts (sticky cells) to capture the prey. 
  • Ctenophora is represented by very few members, hence it is considered as one of the minor phyla. e.g. Pleurobrachia , Ctenoplana.

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