Question

How can we say that sea horse is a fish while jelly fish i not a fish but a coelenterate?

Answer 1

Sea horse is a type of marine fish of genus Hippocampus. Sea horse is a fish because

• It performs respiration using gills.
• It has swim bladder to control its buoyancy.
• It has fins to swim.
• It is classified into Class Actinopterygii which includes bony fishes.

Jellyfishes do not have heart, gills, bones, brains or fins. They do not posses skeletons. Thus they are not fish but coelenterates.