Chapter 4 -animal Kingdom (short note) part 1

Radial symmetry are found in coelenterates,ctenophores, echinoderms.

coelenterates- mesoglea are found.

Platyhelminthes- acoelomates are found.

1- porifera:- fragmentation , Larva name- parenchymula.

In porifera coenocytes are present. Examples- sycon, spongilla (freshwater sponge), Euspongia( bath sponge).

2- phylum coelenterata( cnidaria):-

cnidoblasts present on the tentacles.

Corals have a skeleton composed of calcium carbonate.

. Alternation of generation (metagenesis) i.e polyps produced medusa asexually and meduss form the polyps sexually (eg- obelia) . Example- Hydra, Adamsia, obelia,pennatula(sea- pen) , Gargonia,meandrina( brain coral) .

3:- phylum ctenophora:- sea walnuts or comb jellies.

Bioluminescence ( to emit light) eg- pleurobrachia,ctenoplana.