No they don't have backbones
No, a catfish is a chordate of the vertebrate variety.
An arthropod
As a jelly fish doesn't have a spine, a jelly fish is an invertebrate.
Yes, coral is a cnidarian.
On the field trip, I saw a "cnidarian"when we went on a submarine.**************************A jellyfish is a basic example of a cnidarian.
No, an octopus would be an example of a mollusk (not a cnidarian).
respiratory system is a cnidarian
No- they do not belong to the phylum Cnidarian. They belong to Molluska.
A jelly fish. Cnidarian's have a sting cell called a cnidnocyte which is the defining feature.
No it is not. :)
Cnidarian comes from the Greek/Turkish word "Cnidos" which means stinging nettle
no :P