Which characteristic is not associated with the cnidarians?

Question

Quizplus · Accepted Answer

Cnidarians do have three distinct embryonic cell layers, including the ectoderm, endoderm, and mesoglea. This is a defining characteristic of the phylum. All of the other options are associated with cnidarians. Alternation between polyp and medusa is a common life cycle pattern, nematocysts are stinging organelles used for catching prey or defense, a gastrovascular cavity is a central digestive compartment, and a planula larva is a ciliated, free-swimming stage in the life cycle of some cnidarians.

Which Characteristic Is Not Associated with the Cnidarians