Question: 109. While trying to find out the characteristic of a newly found animal, a researcher did the histology of adult animal and observed a cavity with presence of mesodermal tissue towards the body wall but no mesodermal tissue was observed towards the alimentary canal. What could be the possible coelome of that animal?
(1) Acoelomate
(2) Pseudocoelomate
(3) Schizocoelomate
(4) Spongocoelomate
Answer: Option (2)
Explanation:
A body cavity that is not completely lined by mesoderm is called a pseudocoelom.
In pseudocoelomates, mesoderm is present only towards the body wall.
The mesoderm does not line the alimentary canal.
This condition is characteristic of phylum Nematoda.
Acoelomates lack a body cavity entirely.
Schizocoelomates possess a true coelom fully lined by mesoderm.
Spongocoel is the central cavity of sponges and is not considered a coelom.
Hence, the animal described is a pseudocoelomate.