They are included in phylum echinodermata.
1. they have tube feets.
2. they have a canal system on their body through which they intake and eliminate water.
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Jelly fish come under PHYLUM COELENTERATE.
Characteristics of  PHYLUM COELENTERATE are:
They live in water.They has a sac like body cavity with a single opening to the outside for ingestion and egestion.They are diploblastic.
Star fish come under PHYLUM ECHINODERMATA
Characteristics of PHYLUM ECHINODERMATA:
They are free living marine animal.They are triploblastic.They have calcium carbonate structures that they use as askeleton.
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