Question

Schizocoelomates and enterocoelomates are
A. Acoelomates
B. Invertebrates
C. True coelomates
D. Echinoderms only

Answer 1

Hint: Animals which have a body cavity which is lined by peritoneum are known as true coelomates. The peritoneum is derived from mesoderm which is one the three primary tissue layers.

Complete Answer:
Let us analyze the options and find the correct answer.

Option A: An acoelomate is an animal that does not possess a body cavity. Between the body wall and digestive tract, unlike coelomates, true body cavity animals, acoelomates lack a fluid-filled cavity. Therefore, this is the incorrect option.

Option B: Animals without a backbone or bony skeleton are known as invertebrates. They are an example of true coelomates and include annelids and molluscs. Therefore, this is the incorrect option.

Option C: True coelom is of two types schizocoelom and enterocoelom the true coelom is categorized. Based on ways in which true body cavity or coelom arises in different animals they are categorized. From the mesodermal split Schizocoelom arises. Therefore, this is the correct option.

Option D: Having a radiating arrangement of parts the invertebrate phylum Echinodermata of any marine animal and a body wall stiffened by calcareous pieces that may protrude as spines. They are an example of true coelomates. Therefore, this is the incorrect option.

Thus, the correct option is C) True coelomates.

Note: Schizocoelom - It is found in protostomes and the coelom arises by splitting of the mesoderm. Examples - Annelida, arthropoda.
Enterocoelom- It is found in deuterostomes and the coelom arises by fusion of internal outgrowths. Examples - Echinodermata, chordates.