Question

Charaters of phylem econdodermata

Answer 1

Echinoderms are exclusively marine and there is no parasitic forms.
Firstly I will describe their characters which make echinoderms closer to chordates..
1.They have tube with in tube type if body plan which has evolved along deuterostimic evolutionary line.
2. They posses true coelom called ENTEROCOELOM.
3.They have mesodermal skelton made of calcareous scales and ossicles.
....................,.........................................................................Other characters are :
1.The symmetry is bilateral in larvae but pentamerous radial in adults.
2.Mouth is ventral/oral and anus ia on the dorsal or aboral side.
3.There is no cephalization.
4 Sexes are seperate.They mostly show sexual reproduction.Fertilization is usually external...
5.They have indirect development with a free swimming larval stage.
6.Presence of tube feet is a characteristic feature of this phyla.