In examining an unknown animal species during its embryonic development, from the first development of mouth or anus, one can determine its protostome or deuterostome.
The oral end of the majority of coelomate invertebrates emerges from the blastopore, the first developmental opening, and is referred to as a protostome (Latin for "first mouth").
The oral end of the animal originates from the second aperture on the dorsal surface of the animal in the deuterostomes ("second mouth"), which include Echinodermata and the ancestors of the Chordata; the blastopore becomes the anus. The deuterostomes also exhibit indeterminate development, meaning that even if the eight cells of the embryo are split, each one would still be able to develop into a complete organism.
To learn more about deuterostomes click here
brainly.com/question/12372795
#SPJ4
