An Introduction to Zoology
Chapter Nine: The Radiata: Phylum Cnidaria:
The Eumetazoans:
The eumetazoans, as you recall, are the “true animals.” Unlike the
parazoans, eumetazoan animals possess true
tissues, and most of them have
organs as well. Also unlike the parazoans, all of the eumetazoans have some degree of
body symmetry, and all eumetazoans undergo
embryonic development.
Another thing that distinguishes the eumetazoans is that most of them have two types of tissues that are found in no other living organisms. These tissue types that are unique to eumetazoan animals are
neural (nervous) tissue and
muscular tissue. In most eumetazoans, muscle tissue is attached to some sort of supportive
skeleton – either an internal
endoskeleton or an external
exoskeleton.
Introduction
Linear Mode
