Question

Coelom in Echinoderms is
A. Pseudocoelic
B. Haemocoelic
C. Schizocoelic
D. Enterocoelic

Answer 1

Hint: Animals have a certain hole or cavity-like structures in their body to either help them have buoyancy (if aquatic), excretion, digestion, breathing etc. There are various kinds of coelems depending on the complexity of the microorganism.

Complete answer:
What Are Echinoderms? They are spiny skin organisms. Echinodermata is a phylum under the kingdom Animalia. They have water-filled canals. They have pentameral symmetry. Examples are- starfish, brittle star, sea urchin etc.
What is coelom? A body cavity in the body wall or intestinal canal is a coelom. It could help the microorganism to excrete their internal fluids, act as a skeleton, could be a protective cushion etc.
Let us learn about the terms in the options.
Option A: Pseudocoelic: The simpler phyla like Porifera, protozoa, Platyhelminthes are acoelomate/pseudocoelomate as they do not have a mesodermal line of cells surrounding their coelom.
Option B: Haemocoelic: Animals with haemocoel are haemocoelomate. It means it is a blood-filled body cavity. It is a feature of Arthropoda.
Option C: Schizocoelic: A coelom between digestive tract and musculature of body wall made by the splitting of mesodermal cells is schizocoely. Example-Annelida and Mollusca.
Option D: Enterocoelic: This coelom arises from the endoderm of the embryonic gut. They are formed from the primitive gut which has broken off and formed coelom. Example- Echinodermata and Chordata

So the answer is option D: Enterocoelic.

Note: Enterocoelous is coelom made from pouches pinched off the digestive tract. When the embryo is developing and is in the gastrula stage, the two pockets start to arise from the third germ layer. This folding around the endoderm will make the enterocoel.