3. How useful is the study of the nature of body cavity and coelom in the classification of animals?

Answers (1)
S Sonika

The fluid-filled body cavity derived and lined by mesoderm is called coelom. The study of the nature of the body cavity and coelom is useful because it plays a prominent role in the classification of animals. The animals bearing a coelom are called coelomate while those lacking coelom are called acoelomate. A different type of coelom is also found in animals which are derived from blastocoel of blastula is called pseudocoelom. This coelom is not lined by mesoderm. The coelomates include annelids, molluscs, arthropods, echinoderms, hemichordates and chordates. Aschelminthes are pseudocoelomates. Acoelomates are poriferans, cnidarians, ctenophores and Platyhelminthes.