Question

Text Question:

................ are known to have pseudocoelom.

Answer 1

1. The coelom is a mesoderm lined fluid-filled cavity that occurs between the alimentary canal and body wall.
   On the basis of the presence or absence of coelom, animals are divided into three types:
   (i) Acoelomate: Animals that lack coelom are acoelomate. Examples: Porifera, Coelenterata, Platyhelminthes.
   (ii) Pseudocoelomate: Pseudocoelomate lacks true coelom. A cavity called pseudocoelom is present, which is not lined by mesoderm. Example: Nemathelminthes.
   (iii) Coelomate: A true coelom lined by mesoderm is present. Example: Annelida, Mollusca, Arthropoda, Echinodermata and Chordata.
2. Final Answer: .......Nematodes.......... are known to have pseudocoelom.