Question

The body cavity terms of acoelomate, pseudocoelomate and eu (true) coelomate differentiate animals within what category or categories using the older mophological descriptions?

Answer 1

This type of classification used to be used when classifying the protostome organisms.
In this type of organism, the oral cavity develops from the blastophore, the initial cavity in the gastrula, an early stage of the development of the embryo.